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Author SHA1 Message Date
Linus Torvalds
440d6635b2 mm.git review status for linus..mm-nonmm-stable 
Total patches:       126
 Reviews/patch:       0.92
 Reviewed rate:       76%
 
 - The 2 patch series "pid: make sub-init creation retryable" from Oleg
   Nesterov increases the robustness of our creation of init in a new
   namespace.  By clearing away some historical cruft which is no longer
   needed.  Also some documentation fixups are provided.
 
 - The 2 patch series "selftests/fchmodat2: Error handling and general"
   from Mark Brown has a fixup and a cleanup for the fchmodat2() syscall
   selftest.
 
 - The 3 patch series "lib: polynomial: Move to math/ and clean up" from
   Andy Shevchenko does as advertised.
 
 - The 3 patch series "hung_task: Provide runtime reset interface for
   hung task detector" from Aaron Tomlin gives administrators the ability
   to zero out /proc/sys/kernel/hung_task_detect_count.
 
 - The 2 patch series "tools/getdelays: use the static UAPI headers from
   tools/include/uapi" from Thomas Weißschuh teaches getdelays to use the
   in-kernel UAPI headers rather than the system-provided ones.
 
 - The 5 patch series "watchdog/hardlockup: Improvements to hardlockup"
   from Mayank Rungta provides several cleanups and fixups to the
   hardlockup detector code and its documentation.
 
 - The 2 patch series "lib/bch: fix undefined behavior from signed
   left-shifts" from Josh Law provides a couple of small/theoretical fixes
   in the bch code.
 
 - The 2 patch series "ocfs2/dlm: fix two bugs in dlm_match_regions()"
   from Junrui Luo does what is claims.
 
 - The 27 patch series "cleanup the RAID5 XOR library" from Christoph
   Hellwig is a quite far-reaching cleanup to this code.  I can't do better
   than to quote Christoph:
 
     The XOR library used for the RAID5 parity is a bit of a mess right
     now.  The main file sits in crypto/ despite not being cryptography and
     not using the crypto API, with the generic implementations sitting in
     include/asm-generic and the arch implementations sitting in an asm/
     header in theory.  The latter doesn't work for many cases, so
     architectures often build the code directly into the core kernel, or
     create another module for the architecture code.
 
     Change this to a single module in lib/ that also contains the
     architecture optimizations, similar to the library work Eric Biggers
     has done for the CRC and crypto libraries later.  After that it
     changes to better calling conventions that allow for smarter
     architecture implementations (although none is contained here yet),
     and uses static_call to avoid indirection function call overhead.
 
 - The 2 patch series "lib/list_sort: Clean up list_sort() scheduling
   workarounds" from Kuan-Wei Chiu cleans up this library code by removing
   a hacky thing which was added for UBIFS, which UBIFS doesn't actually
   need.
 
 - The 5 patch series "Fix bugs in extract_iter_to_sg()" from Christian
   Ehrhardt fixes a few bugs in the scatterlist code, adds in-kernel tests
   for the now-fixed bugs and fixes a leak in the test itself.
 
 - The 3 patch series "kdump: Enable LUKS-encrypted dump target support
   in ARM64 and PowerPC" from Coiby Xu eenables support of the
   LUKS-encrypted device dump target on arm64 and powerpc.
 
 - The 4 patch series "ocfs2: consolidate extent list validation into
   block read callbacks" from Joseph Qi addresses ocfs2's validation of
   extent list fields - cleanup, simplification, robustness.  (Kernel test
   robot loves mounting corrupted fs images!)
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Merge tag 'mm-nonmm-stable-2026-04-15-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - "pid: make sub-init creation retryable" (Oleg Nesterov)

   Make creation of init in a new namespace more robust by clearing away
   some historical cruft which is no longer needed. Also some
   documentation fixups

 - "selftests/fchmodat2: Error handling and general" (Mark Brown)

   Fix and a cleanup for the fchmodat2() syscall selftest

 - "lib: polynomial: Move to math/ and clean up" (Andy Shevchenko)

 - "hung_task: Provide runtime reset interface for hung task detector"
   (Aaron Tomlin)

   Give administrators the ability to zero out
   /proc/sys/kernel/hung_task_detect_count

 - "tools/getdelays: use the static UAPI headers from
   tools/include/uapi" (Thomas Weißschuh)

   Teach getdelays to use the in-kernel UAPI headers rather than the
   system-provided ones

 - "watchdog/hardlockup: Improvements to hardlockup" (Mayank Rungta)

   Several cleanups and fixups to the hardlockup detector code and its
   documentation

 - "lib/bch: fix undefined behavior from signed left-shifts" (Josh Law)

   A couple of small/theoretical fixes in the bch code

 - "ocfs2/dlm: fix two bugs in dlm_match_regions()" (Junrui Luo)

 - "cleanup the RAID5 XOR library" (Christoph Hellwig)

   A quite far-reaching cleanup to this code. I can't do better than to
   quote Christoph:

     "The XOR library used for the RAID5 parity is a bit of a mess right
      now. The main file sits in crypto/ despite not being cryptography
      and not using the crypto API, with the generic implementations
      sitting in include/asm-generic and the arch implementations
      sitting in an asm/ header in theory. The latter doesn't work for
      many cases, so architectures often build the code directly into
      the core kernel, or create another module for the architecture
      code.

      Change this to a single module in lib/ that also contains the
      architecture optimizations, similar to the library work Eric
      Biggers has done for the CRC and crypto libraries later. After
      that it changes to better calling conventions that allow for
      smarter architecture implementations (although none is contained
      here yet), and uses static_call to avoid indirection function call
      overhead"

 - "lib/list_sort: Clean up list_sort() scheduling workarounds"
   (Kuan-Wei Chiu)

   Clean up this library code by removing a hacky thing which was added
   for UBIFS, which UBIFS doesn't actually need

 - "Fix bugs in extract_iter_to_sg()" (Christian Ehrhardt)

   Fix a few bugs in the scatterlist code, add in-kernel tests for the
   now-fixed bugs and fix a leak in the test itself

 - "kdump: Enable LUKS-encrypted dump target support in ARM64 and
   PowerPC" (Coiby Xu)

   Enable support of the LUKS-encrypted device dump target on arm64 and
   powerpc

 - "ocfs2: consolidate extent list validation into block read callbacks"
   (Joseph Qi)

   Cleanup, simplify, and make more robust ocfs2's validation of extent
   list fields (Kernel test robot loves mounting corrupted fs images!)

* tag 'mm-nonmm-stable-2026-04-15-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (127 commits)
  ocfs2: validate group add input before caching
  ocfs2: validate bg_bits during freefrag scan
  ocfs2: fix listxattr handling when the buffer is full
  doc: watchdog: fix typos etc
  update Sean's email address
  ocfs2: use get_random_u32() where appropriate
  ocfs2: split transactions in dio completion to avoid credit exhaustion
  ocfs2: remove redundant l_next_free_rec check in __ocfs2_find_path()
  ocfs2: validate extent block list fields during block read
  ocfs2: remove empty extent list check in ocfs2_dx_dir_lookup_rec()
  ocfs2: validate dx_root extent list fields during block read
  ocfs2: fix use-after-free in ocfs2_fault() when VM_FAULT_RETRY
  ocfs2: handle invalid dinode in ocfs2_group_extend
  .get_maintainer.ignore: add Askar
  ocfs2: validate bg_list extent bounds in discontig groups
  checkpatch: exclude forward declarations of const structs
  tools/accounting: handle truncated taskstats netlink messages
  taskstats: set version in TGID exit notifications
  ocfs2/heartbeat: fix slot mapping rollback leaks on error paths
  arm64,ppc64le/kdump: pass dm-crypt keys to kdump kernel
  ...
 2026-04-16 20:11:56 -07:00
Linus Torvalds
334fbe734e mm.git review status for linus..mm-stable 
Everything:
 
 Total patches:       368
 Reviews/patch:       1.56
 Reviewed rate:       74%
 
 Excluding DAMON:
 
 Total patches:       316
 Reviews/patch:       1.77
 Reviewed rate:       81%
 
 Excluding DAMON and zram:
 
 Total patches:       306
 Reviews/patch:       1.81
 Reviewed rate:       82%
 
 Excluding DAMON, zram and maple_tree:
 
 Total patches:       276
 Reviews/patch:       2.01
 Reviewed rate:       91%
 
 Significant patch series in this merge:
 
 - The 30 patch series "maple_tree: Replace big node with maple copy"
   from Liam Howlett is mainly prepararatory work for ongoing development
   but it does reduce stack usage and is an improvement.
 
 - The 12 patch series "mm, swap: swap table phase III: remove swap_map"
   from Kairui Song offers memory savings by removing the static swap_map.
   It also yields some CPU savings and implements several cleanups.
 
 - The 2 patch series "mm: memfd_luo: preserve file seals" from Pratyush
   Yadav adds file seal preservation to LUO's memfd code.
 
 - The 2 patch series "mm: zswap: add per-memcg stat for incompressible
   pages" from Jiayuan Chen adds additional userspace stats reportng to
   zswap.
 
 - The 4 patch series "arch, mm: consolidate empty_zero_page" from Mike
   Rapoport implements some cleanups for our handling of ZERO_PAGE() and
   zero_pfn.
 
 - The 2 patch series "mm/kmemleak: Improve scan_should_stop()
   implementation" from Zhongqiu Han provides an robustness improvement and
   some cleanups in the kmemleak code.
 
 - The 4 patch series "Improve khugepaged scan logic" from Vernon Yang
   "improves the khugepaged scan logic and reduces CPU consumption by
   prioritizing scanning tasks that access memory frequently".
 
 - The 2 patch series "Make KHO Stateless" from Jason Miu simplifies
   Kexec Handover by "transitioning KHO from an xarray-based metadata
   tracking system with serialization to a radix tree data structure that
   can be passed directly to the next kernel"
 
 - The 3 patch series "mm: vmscan: add PID and cgroup ID to vmscan
   tracepoints" from Thomas Ballasi and Steven Rostedt enhances vmscan's
   tracepointing.
 
 - The 5 patch series "mm: arch/shstk: Common shadow stack mapping helper
   and VM_NOHUGEPAGE" from Catalin Marinas is a cleanup for the shadow
   stack code: remove per-arch code in favour of a generic implementation.
 
 - The 2 patch series "Fix KASAN support for KHO restored vmalloc
   regions" from Pasha Tatashin fixes a WARN() which can be emitted the KHO
   restores a vmalloc area.
 
 - The 4 patch series "mm: Remove stray references to pagevec" from Tal
   Zussman provides several cleanups, mainly udpating references to "struct
   pagevec", which became folio_batch three years ago.
 
 - The 17 patch series "mm: Eliminate fake head pages from vmemmap
   optimization" from Kiryl Shutsemau simplifies the HugeTLB vmemmap
   optimization (HVO) by changing how tail pages encode their relationship
   to the head page.
 
 - The 2 patch series "mm/damon/core: improve DAMOS quota efficiency for
   core layer filters" from SeongJae Park improves two problematic
   behaviors of DAMOS that makes it less efficient when core layer filters
   are used.
 
 - The 3 patch series "mm/damon: strictly respect min_nr_regions" from
   SeongJae Park improves DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter.
 
 - The 3 patch series "mm/page_alloc: pcp locking cleanup" from Vlastimil
   Babka is a proper fix for a previously hotfixed SMP=n issue.  Code
   simplifications and cleanups ennsed.
 
 - The 16 patch series "mm: cleanups around unmapping / zapping" from
   David Hildenbrand implements "a bunch of cleanups around unmapping and
   zapping.  Mostly simplifications, code movements, documentation and
   renaming of zapping functions".
 
 - The 6 patch series "support batched checking of the young flag for
   MGLRU" from Baolin Wang supports batched checking of the young flag for
   MGLRU.  It's part cleanups; one benchmark shows large performance
   benefits for arm64.
 
 - The 5 patch series "memcg: obj stock and slab stat caching cleanups"
   from Johannes Weiner provides memcg cleanup and robustness improvements.
 
 - The 5 patch series "Allow order zero pages in page reporting" from
   Yuvraj Sakshith enhances page_reporting's free page reporting - it is
   presently and undesirably order-0 pages when reporting free memory.
 
 - The 6 patch series "mm: vma flag tweaks" from Lorenzo Stoakes is
   cleanup work following from the recent conversion of the VMA flags to a
   bitmap.
 
 - The 10 patch series "mm/damon: add optional debugging-purpose sanity
   checks" from SeongJae Park adds some more developer-facing debug checks
   into DAMON core.
 
 - The 2 patch series "mm/damon: test and document power-of-2
   min_region_sz requirement" from SeongJae Park adds an additional DAMON
   kunit test and makes some adjustments to the addr_unit parameter
   handling.
 
 - The 3 patch series "mm/damon/core: make passed_sample_intervals
   comparisons overflow-safe" from SeongJae Park fixes a hard-to-hit time
   overflow issue in DAMON core.
 
 - The 7 patch series "mm/damon: improve/fixup/update ratio calculation,
   test and documentation" from SeongJae Park is a "batch of misc/minor
   improvements and fixups" for DAMON.
 
 - The 4 patch series "mm: move vma_(kernel|mmu)_pagesize() out of
   hugetlb.c" from David Hildenbrand fixes a possible issue with dax-device
   when CONFIG_HUGETLB=n.  Some code movement was required.
 
 - The 6 patch series "zram: recompression cleanups and tweaks" from
   Sergey Senozhatsky provides "a somewhat random mix of fixups,
   recompression cleanups and improvements" in the zram code.
 
 - The 11 patch series "mm/damon: support multiple goal-based quota
   tuning algorithms" from SeongJae Park extend DAMOS quotas goal
   auto-tuning to support multiple tuning algorithms that users can select.
 
 - The 4 patch series "mm: thp: reduce unnecessary
   start_stop_khugepaged()" from Breno Leitao fixes the khugpaged sysfs
   handling so we no longer spam the logs with reams of junk when
   starting/stopping khugepaged.
 
 - The 3 patch series "mm: improve map count checks" from Lorenzo Stoakes
   provides some cleanups and slight fixes in the mremap, mmap and vma
   code.
 
 - The 5 patch series "mm/damon: support addr_unit on default monitoring
   targets for modules" from SeongJae Park extends the use of DAMON core's
   addr_unit tunable.
 
 - The 5 patch series "mm: khugepaged cleanups and mTHP prerequisites"
   from Nico Pache provides cleanups in the khugepaged and is a base for
   Nico's planned khugepaged mTHP support.
 
 - The 15 patch series "mm: memory hot(un)plug and SPARSEMEM cleanups"
   from David Hildenbrand implements code movement and cleanups in the
   memhotplug and sparsemem code.
 
 - The 2 patch series "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and
   cleanup CONFIG_MIGRATION" from David Hildenbrand rationalizes some
   memhotplug Kconfig support.
 
 - The 6 patch series "change young flag check functions to return bool"
   from Baolin Wang is "a cleanup patchset to change all young flag check
   functions to return bool".
 
 - The 3 patch series "mm/damon/sysfs: fix memory leak and NULL
   dereference issues" from Josh Law and SeongJae Park fixes a few
   potential DAMON bugs.
 
 - The 25 patch series "mm/vma: convert vm_flags_t to vma_flags_t in vma
   code" from "converts a lot of the existing use of the legacy vm_flags_t
   data type to the new vma_flags_t type which replaces it".  Mainly in the
   vma code.
 
 - The 21 patch series "mm: expand mmap_prepare functionality and usage"
   from Lorenzo Stoakes "expands the mmap_prepare functionality, which is
   intended to replace the deprecated f_op->mmap hook which has been the
   source of bugs and security issues for some time".  Cleanups,
   documentation, extension of mmap_prepare into filesystem drivers.
 
 - The 13 patch series "mm/huge_memory: refactor zap_huge_pmd()" from
   Lorenzo Stoakes simplifies and cleans up zap_huge_pmd().  Additional
   cleanups around vm_normal_folio_pmd() and the softleaf functionality are
   performed.
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Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - "maple_tree: Replace big node with maple copy" (Liam Howlett)

   Mainly prepararatory work for ongoing development but it does reduce
   stack usage and is an improvement.

 - "mm, swap: swap table phase III: remove swap_map" (Kairui Song)

   Offers memory savings by removing the static swap_map. It also yields
   some CPU savings and implements several cleanups.

 - "mm: memfd_luo: preserve file seals" (Pratyush Yadav)

   File seal preservation to LUO's memfd code

 - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan
   Chen)

   Additional userspace stats reportng to zswap

 - "arch, mm: consolidate empty_zero_page" (Mike Rapoport)

   Some cleanups for our handling of ZERO_PAGE() and zero_pfn

 - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu
   Han)

   A robustness improvement and some cleanups in the kmemleak code

 - "Improve khugepaged scan logic" (Vernon Yang)

   Improve khugepaged scan logic and reduce CPU consumption by
   prioritizing scanning tasks that access memory frequently

 - "Make KHO Stateless" (Jason Miu)

   Simplify Kexec Handover by transitioning KHO from an xarray-based
   metadata tracking system with serialization to a radix tree data
   structure that can be passed directly to the next kernel

 - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas
   Ballasi and Steven Rostedt)

   Enhance vmscan's tracepointing

 - "mm: arch/shstk: Common shadow stack mapping helper and
   VM_NOHUGEPAGE" (Catalin Marinas)

   Cleanup for the shadow stack code: remove per-arch code in favour of
   a generic implementation

 - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin)

   Fix a WARN() which can be emitted the KHO restores a vmalloc area

 - "mm: Remove stray references to pagevec" (Tal Zussman)

   Several cleanups, mainly udpating references to "struct pagevec",
   which became folio_batch three years ago

 - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl
   Shutsemau)

   Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail
   pages encode their relationship to the head page

 - "mm/damon/core: improve DAMOS quota efficiency for core layer
   filters" (SeongJae Park)

   Improve two problematic behaviors of DAMOS that makes it less
   efficient when core layer filters are used

 - "mm/damon: strictly respect min_nr_regions" (SeongJae Park)

   Improve DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter

 - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka)

   The proper fix for a previously hotfixed SMP=n issue. Code
   simplifications and cleanups ensued

 - "mm: cleanups around unmapping / zapping" (David Hildenbrand)

   A bunch of cleanups around unmapping and zapping. Mostly
   simplifications, code movements, documentation and renaming of
   zapping functions

 - "support batched checking of the young flag for MGLRU" (Baolin Wang)

   Batched checking of the young flag for MGLRU. It's part cleanups; one
   benchmark shows large performance benefits for arm64

 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner)

   memcg cleanup and robustness improvements

 - "Allow order zero pages in page reporting" (Yuvraj Sakshith)

   Enhance free page reporting - it is presently and undesirably order-0
   pages when reporting free memory.

 - "mm: vma flag tweaks" (Lorenzo Stoakes)

   Cleanup work following from the recent conversion of the VMA flags to
   a bitmap

 - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae
   Park)

   Add some more developer-facing debug checks into DAMON core

 - "mm/damon: test and document power-of-2 min_region_sz requirement"
   (SeongJae Park)

   An additional DAMON kunit test and makes some adjustments to the
   addr_unit parameter handling

 - "mm/damon/core: make passed_sample_intervals comparisons
   overflow-safe" (SeongJae Park)

   Fix a hard-to-hit time overflow issue in DAMON core

 - "mm/damon: improve/fixup/update ratio calculation, test and
   documentation" (SeongJae Park)

   A batch of misc/minor improvements and fixups for DAMON

 - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David
   Hildenbrand)

   Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code
   movement was required.

 - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky)

   A somewhat random mix of fixups, recompression cleanups and
   improvements in the zram code

 - "mm/damon: support multiple goal-based quota tuning algorithms"
   (SeongJae Park)

   Extend DAMOS quotas goal auto-tuning to support multiple tuning
   algorithms that users can select

 - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao)

   Fix the khugpaged sysfs handling so we no longer spam the logs with
   reams of junk when starting/stopping khugepaged

 - "mm: improve map count checks" (Lorenzo Stoakes)

   Provide some cleanups and slight fixes in the mremap, mmap and vma
   code

 - "mm/damon: support addr_unit on default monitoring targets for
   modules" (SeongJae Park)

   Extend the use of DAMON core's addr_unit tunable

 - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache)

   Cleanups to khugepaged and is a base for Nico's planned khugepaged
   mTHP support

 - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand)

   Code movement and cleanups in the memhotplug and sparsemem code

 - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
   CONFIG_MIGRATION" (David Hildenbrand)

   Rationalize some memhotplug Kconfig support

 - "change young flag check functions to return bool" (Baolin Wang)

   Cleanups to change all young flag check functions to return bool

 - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh
   Law and SeongJae Park)

   Fix a few potential DAMON bugs

 - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo
   Stoakes)

   Convert a lot of the existing use of the legacy vm_flags_t data type
   to the new vma_flags_t type which replaces it. Mainly in the vma
   code.

 - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes)

   Expand the mmap_prepare functionality, which is intended to replace
   the deprecated f_op->mmap hook which has been the source of bugs and
   security issues for some time. Cleanups, documentation, extension of
   mmap_prepare into filesystem drivers

 - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes)

   Simplify and clean up zap_huge_pmd(). Additional cleanups around
   vm_normal_folio_pmd() and the softleaf functionality are performed.

* tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm: fix deferred split queue races during migration
  mm/khugepaged: fix issue with tracking lock
  mm/huge_memory: add and use has_deposited_pgtable()
  mm/huge_memory: add and use normal_or_softleaf_folio_pmd()
  mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio()
  mm/huge_memory: separate out the folio part of zap_huge_pmd()
  mm/huge_memory: use mm instead of tlb->mm
  mm/huge_memory: remove unnecessary sanity checks
  mm/huge_memory: deduplicate zap deposited table call
  mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
  mm/huge_memory: add a common exit path to zap_huge_pmd()
  mm/huge_memory: handle buggy PMD entry in zap_huge_pmd()
  mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc
  mm/huge: avoid big else branch in zap_huge_pmd()
  mm/huge_memory: simplify vma_is_specal_huge()
  mm: on remap assert that input range within the proposed VMA
  mm: add mmap_action_map_kernel_pages[_full]()
  uio: replace deprecated mmap hook with mmap_prepare in uio_info
  drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare
  mm: allow handling of stacked mmap_prepare hooks in more drivers
  ...
 2026-04-15 12:59:16 -07:00
Linus Torvalds
4a57e0913e drm for v7.1-rc1 
mm:
 - two pass MMU interval notifiers
 - add gpu active/reclaim per-node stat counters
 
 math:
 - provide __KERNEL_DIV_ROUND_CLOSEST() in UAPI
 - implement DIV_ROUND_CLOSEST() with __KERNEL_DIV_ROUND_CLOSEST()
 
 rust:
 - shared tag with driver-core: register macro and io infra
 - core: rework DMA coherent API
 - core: add interop::list to interop with C linked lists
 - core: add more num::Bounded operations
 - core: enable generic_arg_infer and add EMSGSIZE
 - workqueue: add ARef<T> support for work and delayed work
 - add GPU buddy allocator abstraction
 - add DRM shmem GEM helper abstraction
 - allow drm:::Device to dispatch work and delayed work items
   to driver private data
 - add dma_resv_lock helper and raw accessors
 
 core:
 - introduce DRM RAS infrastructure over netlink
 - add connector panel_type property
 - fourcc: add ARM interleaved 64k modifier
 - colorop: add destroy helper
 - suballoc: split into alloc and init helpers
 - mode: provide DRM_ARGB_GET*() macros for reading color components
 
 edid:
 - provide drm_output_color_Format
 
 dma-buf:
 - provide revoke mechanism for shared buffers
 - rename move_notify to invalidate_mappings
 - always enable move_notify
 - protect dma_fence_ops with RCU and improve locking
 - clean pages with helpers
 
 atomic:
 - allocate drm_private_state via callback
 - helper: use system_percpu_wq
 
 buddy:
 - make buddy allocator available to gpu level
 - add kernel-doc for buddy allocator
 - improve aligned allocation
 
 ttm:
 - fix fence signalling
 - improve tests and docs
 - improve handling of gfp_retry_mayfail
 - use per-node stat counters to track memory allocations
 - port pool to use list_lru
 - drop NUMA specific pools
 - make pool shrinker numa aware
 - track allocated pages per numa node
 
 coreboot:
 - cleanup coreboot framebuffer support
 
 sched:
 - fix race condition in drm_sched_fini
 
 pagemap:
 - enable THP support
 - pass pagemap_addr by reference
 
 gem-shmem:
 - Track page accessed/dirty status across mmap/vmap
 
 gpusvm:
 - reenable device to device migration
 - fix unbalanced unclock
 
 bridge:
 - anx7625: Support USB-C plus DT bindings
 - connector: Fix EDID detection
 - dw-hdmi-qp: Support Vendor-Specfic and SDP Infoframes; improve others
 - fsl-ldb: Fix visual artifacts plus related DT property 'enable-termination-resistor'
 - imx8qxp-pixel-link: Improve bridge reference handling
 - lt9611: Support Port-B-only input plus DT bindings
 - tda998x: Support DRM_BRIDGE_ATTACH_NO_CONNECTOR; Clean up
 - Support TH1520 HDMI plus DT bindings
 - waveshare-dsi: Fix register and attach; Support 1..4 DSI lanes plus DT bindings
 - anx7625: Fix USB Type-C handling
 - cdns-mhdp8546-core: Handle HDCP state in bridge atomic_check
 - Support Lontium LT8713SX DP MST bridge plus DT bindings
 - analogix_dp: Use DP helpers for link training
 
 panel:
 - panel-jdi-lt070me05000: Use mipi-dsi multi functions
 - panel-edp: Support Add AUO B116XAT04.1 (HW: 1A); Support CMN N116BCL-EAK (C2); Support FriendlyELEC plus DT changes
 - panel-edp: Fix timings for BOE NV140WUM-N64
 - ilitek-ili9882t: Allow GPIO calls to sleep
 - jadard: Support TAIGUAN XTI05101-01A
 - lxd: Support LXD M9189A plus DT bindings
 - mantix: Fix pixel clock; Clean up
 - motorola: Support Motorola Atrix 4G and Droid X2 plus DT bindings
 - novatek: Support Novatek/Tianma NT37700F plus DT bindings
 - simple: Support EDT ET057023UDBA plus DT bindings; Support Powertip
   PH800480T032-ZHC19 plus DT bindings; Support Waveshare 13.3"
 - novatek-nt36672a: Use mipi_dsi_*_multi() functions
 - panel-edp: Support BOE NV153WUM-N42, CMN N153JCA-ELK, CSW MNF307QS3-2
 - support Himax HX83121A plus DT bindings
 - support JuTouch JT070TM041 plus DT bindings
 - support Samsung S6E8FC0 plus DT bindings
 - himax-hx83102c: support Samsung S6E8FC0 plus DT bindings; support backlight
 - ili9806e: support Rocktech RK050HR345-CT106A plus DT bindings
 - simple: support Tianma TM050RDH03 plus DT bindings
 
 amdgpu:
 - enable DC by default on CIK APUs
 - userq fence ioctl param size fixes
 - set panel_type to OLED for eDP
 - refactor DC i2c code
 - FAMS2 update
 - rework ttm handling to allow multiple engines
 - DC DCE 6.x cleanup
 - DC support for NUTMEG/TRAVIS DP bridge
 - DCN 4.2 support
 - GC12 idle power fix for compute
 - use struct drm_edid in non-DC code
 - enable NV12/P010 support on primary planes
 - support newer IP discovery tables
 - VCN/JPEG 5.0.2 support
 - GC/MES 12.1 updates
 - USERQ fixes
 - add DC idle state manager
 - eDP DSC seamless boot
 
 amdkfd:
 - GC 12.1 updates
 - non 4K page fixes
 
 xe:
 - basic Xe3p_LPG and NVL-P enabling patches
 - allow VM_BIND decompress support
 - add purgeable buffer object support
 - add xe_vm_get_property_ioctl
 - restrict multi-lrc to VCS/VECS engines
 - allow disabling VM overcommit in fault mode
 - dGPU memory optimizations
 - Workaround cleanups and simplification
 - Allow VFs VRAM quote changes using sysfs
 - convert GT stats to per-cpu counters
 - pagefault refactors
 - enable multi-queue on xe3p_xpc
 - disable DCC on PTL
 - make MMIO communication more robust
 - disable D3Cold for BMG on specific platforms
 - vfio: improve FLR sync for Xe VFIO
 
 i915/display:
 - C10/C20/LT PHY PLL divider verification
 - use trans push mechanism to generate PSR frame change on LNL+
 - refactor DP DSC slice config
 - VGA decode refactoring
 - refactor DPT, gen2-4 overlay, masked field register macro helpers
 - refactor stolen memory allocation decisions
 - prepare for UHBR DP tunnels
 - refactor LT PHY PLL to use DPLL framework
 - implement register polling/waiting in display code
 - add shared stepping header between i915 and display
 
 i915:
 - fix potential overflow of shmem scatterlist length
 
 nouveau:
 - provide Z cull info to userspace
 - initial GA100 support
 - shutdown on PCI device shutdown
 
 nova-core:
 - harden GSP command queue
 - add support for large RPCs
 - simplify GSP sequencer and message handling
 - refactor falcon firmware handling
 - convert to new register macro
 - conver to new DMA coherent API
 - use checked arithmetic
 - add debugfs support for gsp-rm log buffers
 - fix aux device registration for multi-GPU
 
 msm:
 - CI:
   - Uprev mesa
   - Restore CI jobs for Qualcomm APQ8016 and APQ8096 devices
 - Core:
   - Switched to of_get_available_child_by_name()
 - DPU:
   - Fixes for DSC panels
   - Fixed brownout because of the frequency / OPP mismatch
   - Quad pipe preparation (not enabled yet)
   - Switched to virtual planes by default
   - Dropped VBIF_NRT support
   - Added support for Eliza platform
   - Reworked alpha handling
   - Switched to correct CWB definitions on Eliza
   - Dropped dummy INTF_0 on MSM8953
   - Corrected INTFs related to DP-MST
 - DP:
   - Removed debug prints looking into PHY internals
 - DSI:
   - Fixes for DSC panels
   - RGB101010 support
   - Support for SC8280XP
   - Moved PHY bindings from display/ to phy/
 - GPU:
   - Preemption support for x2-85 and a840
   - IFPC support for a840
   - SKU detection support for x2-85 and a840
   - Expose AQE support (VK ray-pipeline)
   - Avoid locking in VM_BIND fence signaling path
   - Fix to avoid reclaim in GPU snapshot path
   - Disallow foreign mapping of _NO_SHARE BOs
 - HDMI:
   - Fixed infoframes programming
 - MDP5:
   - Dropped support for MSM8974v1
   - Dropped now unused code for MSM8974 v1 and SDM660 / MSM8998
 
 panthor:
 - add tracepoints for power and IRQs
 - fix fence handling
 - extend timestamp query with flags
 - support various sources for timestamp queries
 
 tyr:
 - fix names and model/versions
 
 rockchip:
 - vop2: use drm logging function
 - rk3576 displayport support
 - support CRTC background color
 
 atmel-hlcdc:
 - support sana5d65 LCD controller
 
 tilcdc:
 - use DT bindings schema
 - use managed DRM interfaces
 - support DRM_BRIDGE_ATTACH_NO_CONNECTOR
 
 verisilicon:
 - support DC8200 + DT bindings
 
 virtgpu:
 - support PRIME import with 3D enabled
 
 komeda:
 - fix integer overflow in AFBC checks
 
 mcde:
 - improve bridge handling
 
 gma500:
 - use drm client buffer for fbdev framebuffer
 
 amdxdna:
 - add sensors ioctls
 - provide NPU power estimate
 - support column utilization sensor
 - allow forcing DMA through IOMMU IOVA
 - support per-BO mem usage queries
 - refactor GEM implementation
 
 ivpu:
 - update boot API to v3.29.4
 - limit per-user number of doorbells/contexts
 - perform engine reset on TDR error
 
 loongson:
 - replace custom code with drm_gem_ttm_dumb_map_offset()
 
 imx:
 - support planes behind the primary plane
 - fix bus-format selection
 
 vkms:
 - support CRTC background color
 
 v3d:
 - improve handling of struct v3d_stats
 
 komeda:
 - support Arm China Linlon D6 plus DT bindings
 
 imagination:
 - improve power-off sequence
 - support context-reset notification from firmware
 
 mediatek:
 - mtk_dsi: enable hs clock during pre-enable
 - Remove all conflicting aperture devices during probe
 - Add support for mt8167 display blocks
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Merge tag 'drm-next-2026-04-15' of https://gitlab.freedesktop.org/drm/kernel

Pull drm updates from Dave Airlie:
 "Highlights:
   - new DRM RAS infrastructure using netlink
   - amdgpu: enable DC on CIK APUs, and more IP enablement, and more
     user queue work
   - xe: purgeable BO support, and new hw enablement
   - dma-buf : add revocable operations

  Full summary:

  mm:
   - two-pass MMU interval notifiers
   - add gpu active/reclaim per-node stat counters

  math:
   - provide __KERNEL_DIV_ROUND_CLOSEST() in UAPI
   - implement DIV_ROUND_CLOSEST() with __KERNEL_DIV_ROUND_CLOSEST()

  rust:
   - shared tag with driver-core: register macro and io infra
   - core: rework DMA coherent API
   - core: add interop::list to interop with C linked lists
   - core: add more num::Bounded operations
   - core: enable generic_arg_infer and add EMSGSIZE
   - workqueue: add ARef<T> support for work and delayed work
   - add GPU buddy allocator abstraction
   - add DRM shmem GEM helper abstraction
   - allow drm:::Device to dispatch work and delayed work items
     to driver private data
   - add dma_resv_lock helper and raw accessors

  core:
   - introduce DRM RAS infrastructure over netlink
   - add connector panel_type property
   - fourcc: add ARM interleaved 64k modifier
   - colorop: add destroy helper
   - suballoc: split into alloc and init helpers
   - mode: provide DRM_ARGB_GET*() macros for reading color components

  edid:
   - provide drm_output_color_Format

  dma-buf:
   - provide revoke mechanism for shared buffers
   - rename move_notify to invalidate_mappings
   - always enable move_notify
   - protect dma_fence_ops with RCU and improve locking
   - clean pages with helpers

  atomic:
   - allocate drm_private_state via callback
   - helper: use system_percpu_wq

  buddy:
   - make buddy allocator available to gpu level
   - add kernel-doc for buddy allocator
   - improve aligned allocation

  ttm:
   - fix fence signalling
   - improve tests and docs
   - improve handling of gfp_retry_mayfail
   - use per-node stat counters to track memory allocations
   - port pool to use list_lru
   - drop NUMA specific pools
   - make pool shrinker numa aware
   - track allocated pages per numa node

  coreboot:
   - cleanup coreboot framebuffer support

  sched:
   - fix race condition in drm_sched_fini

  pagemap:
   - enable THP support
   - pass pagemap_addr by reference

  gem-shmem:
   - Track page accessed/dirty status across mmap/vmap

  gpusvm:
   - reenable device to device migration
   - fix unbalanced unclock

  bridge:
   - anx7625: Support USB-C plus DT bindings
   - connector: Fix EDID detection
   - dw-hdmi-qp: Support Vendor-Specfic and SDP Infoframes; improve
     others
   - fsl-ldb: Fix visual artifacts plus related DT property
     'enable-termination-resistor'
   - imx8qxp-pixel-link: Improve bridge reference handling
   - lt9611: Support Port-B-only input plus DT bindings
   - tda998x: Support DRM_BRIDGE_ATTACH_NO_CONNECTOR; Clean up
   - Support TH1520 HDMI plus DT bindings
   - waveshare-dsi: Fix register and attach; Support 1..4 DSI lanes plus
     DT bindings
   - anx7625: Fix USB Type-C handling
   - cdns-mhdp8546-core: Handle HDCP state in bridge atomic_check
   - Support Lontium LT8713SX DP MST bridge plus DT bindings
   - analogix_dp: Use DP helpers for link training

  panel:
   - panel-jdi-lt070me05000: Use mipi-dsi multi functions
   - panel-edp: Support Add AUO B116XAT04.1 (HW: 1A); Support CMN
     N116BCL-EAK (C2); Support FriendlyELEC plus DT changes
   - panel-edp: Fix timings for BOE NV140WUM-N64
   - ilitek-ili9882t: Allow GPIO calls to sleep
   - jadard: Support TAIGUAN XTI05101-01A
   - lxd: Support LXD M9189A plus DT bindings
   - mantix: Fix pixel clock; Clean up
   - motorola: Support Motorola Atrix 4G and Droid X2 plus DT bindings
   - novatek: Support Novatek/Tianma NT37700F plus DT bindings
   - simple: Support EDT ET057023UDBA plus DT bindings; Support Powertip
     PH800480T032-ZHC19 plus DT bindings; Support Waveshare 13.3"
   - novatek-nt36672a: Use mipi_dsi_*_multi() functions
   - panel-edp: Support BOE NV153WUM-N42, CMN N153JCA-ELK, CSW
     MNF307QS3-2
   - support Himax HX83121A plus DT bindings
   - support JuTouch JT070TM041 plus DT bindings
   - support Samsung S6E8FC0 plus DT bindings
   - himax-hx83102c: support Samsung S6E8FC0 plus DT bindings; support
     backlight
   - ili9806e: support Rocktech RK050HR345-CT106A plus DT bindings
   - simple: support Tianma TM050RDH03 plus DT bindings

  amdgpu:
   - enable DC by default on CIK APUs
   - userq fence ioctl param size fixes
   - set panel_type to OLED for eDP
   - refactor DC i2c code
   - FAMS2 update
   - rework ttm handling to allow multiple engines
   - DC DCE 6.x cleanup
   - DC support for NUTMEG/TRAVIS DP bridge
   - DCN 4.2 support
   - GC12 idle power fix for compute
   - use struct drm_edid in non-DC code
   - enable NV12/P010 support on primary planes
   - support newer IP discovery tables
   - VCN/JPEG 5.0.2 support
   - GC/MES 12.1 updates
   - USERQ fixes
   - add DC idle state manager
   - eDP DSC seamless boot

  amdkfd:
   - GC 12.1 updates
   - non 4K page fixes

  xe:
   - basic Xe3p_LPG and NVL-P enabling patches
   - allow VM_BIND decompress support
   - add purgeable buffer object support
   - add xe_vm_get_property_ioctl
   - restrict multi-lrc to VCS/VECS engines
   - allow disabling VM overcommit in fault mode
   - dGPU memory optimizations
   - Workaround cleanups and simplification
   - Allow VFs VRAM quote changes using sysfs
   - convert GT stats to per-cpu counters
   - pagefault refactors
   - enable multi-queue on xe3p_xpc
   - disable DCC on PTL
   - make MMIO communication more robust
   - disable D3Cold for BMG on specific platforms
   - vfio: improve FLR sync for Xe VFIO

  i915/display:
   - C10/C20/LT PHY PLL divider verification
   - use trans push mechanism to generate PSR frame change on LNL+
   - refactor DP DSC slice config
   - VGA decode refactoring
   - refactor DPT, gen2-4 overlay, masked field register macro helpers
   - refactor stolen memory allocation decisions
   - prepare for UHBR DP tunnels
   - refactor LT PHY PLL to use DPLL framework
   - implement register polling/waiting in display code
   - add shared stepping header between i915 and display

  i915:
   - fix potential overflow of shmem scatterlist length

  nouveau:
   - provide Z cull info to userspace
   - initial GA100 support
   - shutdown on PCI device shutdown

  nova-core:
   - harden GSP command queue
   - add support for large RPCs
   - simplify GSP sequencer and message handling
   - refactor falcon firmware handling
   - convert to new register macro
   - conver to new DMA coherent API
   - use checked arithmetic
   - add debugfs support for gsp-rm log buffers
   - fix aux device registration for multi-GPU

  msm:
   - CI:
      - Uprev mesa
      - Restore CI jobs for Qualcomm APQ8016 and APQ8096 devices
   - Core:
      - Switched to of_get_available_child_by_name()
   - DPU:
      - Fixes for DSC panels
      - Fixed brownout because of the frequency / OPP mismatch
      - Quad pipe preparation (not enabled yet)
      - Switched to virtual planes by default
      - Dropped VBIF_NRT support
      - Added support for Eliza platform
      - Reworked alpha handling
      - Switched to correct CWB definitions on Eliza
      - Dropped dummy INTF_0 on MSM8953
      - Corrected INTFs related to DP-MST
   - DP:
      - Removed debug prints looking into PHY internals
   - DSI:
      - Fixes for DSC panels
      - RGB101010 support
      - Support for SC8280XP
      - Moved PHY bindings from display/ to phy/
   - GPU:
      - Preemption support for x2-85 and a840
      - IFPC support for a840
      - SKU detection support for x2-85 and a840
      - Expose AQE support (VK ray-pipeline)
      - Avoid locking in VM_BIND fence signaling path
      - Fix to avoid reclaim in GPU snapshot path
      - Disallow foreign mapping of _NO_SHARE BOs
   - HDMI:
      - Fixed infoframes programming
   - MDP5:
      - Dropped support for MSM8974v1
      - Dropped now unused code for MSM8974 v1 and SDM660 / MSM8998

  panthor:
   - add tracepoints for power and IRQs
   - fix fence handling
   - extend timestamp query with flags
   - support various sources for timestamp queries

  tyr:
   - fix names and model/versions

  rockchip:
   - vop2: use drm logging function
   - rk3576 displayport support
   - support CRTC background color

  atmel-hlcdc:
   - support sana5d65 LCD controller

  tilcdc:
   - use DT bindings schema
   - use managed DRM interfaces
   - support DRM_BRIDGE_ATTACH_NO_CONNECTOR

  verisilicon:
   - support DC8200 + DT bindings

  virtgpu:
   - support PRIME import with 3D enabled

  komeda:
   - fix integer overflow in AFBC checks

  mcde:
   - improve bridge handling

  gma500:
   - use drm client buffer for fbdev framebuffer

  amdxdna:
   - add sensors ioctls
   - provide NPU power estimate
   - support column utilization sensor
   - allow forcing DMA through IOMMU IOVA
   - support per-BO mem usage queries
   - refactor GEM implementation

  ivpu:
   - update boot API to v3.29.4
   - limit per-user number of doorbells/contexts
   - perform engine reset on TDR error

  loongson:
   - replace custom code with drm_gem_ttm_dumb_map_offset()

  imx:
   - support planes behind the primary plane
   - fix bus-format selection

  vkms:
   - support CRTC background color

  v3d:
   - improve handling of struct v3d_stats

  komeda:
   - support Arm China Linlon D6 plus DT bindings

  imagination:
   - improve power-off sequence
   - support context-reset notification from firmware

  mediatek:
   - mtk_dsi: enable hs clock during pre-enable
   - Remove all conflicting aperture devices during probe
   - Add support for mt8167 display blocks"

* tag 'drm-next-2026-04-15' of https://gitlab.freedesktop.org/drm/kernel: (1735 commits)
  drm/ttm/tests: Remove checks from ttm_pool_free_no_dma_alloc
  drm/ttm/tests: fix lru_count ASSERT
  drm/vram: remove DRM_VRAM_MM_FILE_OPERATIONS from docs
  drm/fb-helper: Fix a locking bug in an error path
  dma-fence: correct kernel-doc function parameter @flags
  ttm/pool: track allocated_pages per numa node.
  ttm/pool: make pool shrinker NUMA aware (v2)
  ttm/pool: drop numa specific pools
  ttm/pool: port to list_lru. (v2)
  drm/ttm: use gpu mm stats to track gpu memory allocations. (v4)
  mm: add gpu active/reclaim per-node stat counters (v2)
  gpu: nova-core: fix missing colon in SEC2 boot debug message
  gpu: nova-core: vbios: use from_le_bytes() for PCI ROM header parsing
  gpu: nova-core: bitfield: fix broken Default implementation
  gpu: nova-core: falcon: pad firmware DMA object size to required block alignment
  gpu: nova-core: gsp: fix undefined behavior in command queue code
  drm/shmem_helper: Make sure PMD entries get the writeable upgrade
  accel/ivpu: Trigger recovery on TDR with OS scheduling
  drm/msm: Use of_get_available_child_by_name()
  dt-bindings: display/msm: move DSI PHY bindings to phy/ subdir
  ...
 2026-04-15 08:45:00 -07:00
Linus Torvalds
ef3da345cc vfs-7.1-rc1.misc 
Please consider pulling these changes from the signed vfs-7.1-rc1.misc tag.
 
 Thanks!
 Christian
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Merge tag 'vfs-7.1-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull misc vfs updates from Christian Brauner:
 "Features:
   - coredump: add tracepoint for coredump events
   - fs: hide file and bfile caches behind runtime const machinery

  Fixes:
   - fix architecture-specific compat_ftruncate64 implementations
   - dcache: Limit the minimal number of bucket to two
   - fs/omfs: reject s_sys_blocksize smaller than OMFS_DIR_START
   - fs/mbcache: cancel shrink work before destroying the cache
   - dcache: permit dynamic_dname()s up to NAME_MAX

  Cleanups:
   - remove or unexport unused fs_context infrastructure
   - trivial ->setattr cleanups
   - selftests/filesystems: Assume that TIOCGPTPEER is defined
   - writeback: fix kernel-doc function name mismatch for wb_put_many()
   - autofs: replace manual symlink buffer allocation in autofs_dir_symlink
   - init/initramfs.c: trivial fix: FSM -> Finite-state machine
   - fs: remove stale and duplicate forward declarations
   - readdir: Introduce dirent_size()
   - fs: Replace user_access_{begin/end} by scoped user access
   - kernel: acct: fix duplicate word in comment
   - fs: write a better comment in step_into() concerning .mnt assignment
   - fs: attr: fix comment formatting and spelling issues"

* tag 'vfs-7.1-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (28 commits)
  dcache: permit dynamic_dname()s up to NAME_MAX
  fs: attr: fix comment formatting and spelling issues
  fs: hide file and bfile caches behind runtime const machinery
  fs: write a better comment in step_into() concerning .mnt assignment
  proc: rename proc_notify_change to proc_setattr
  proc: rename proc_setattr to proc_nochmod_setattr
  affs: rename affs_notify_change to affs_setattr
  adfs: rename adfs_notify_change to adfs_setattr
  hfs: update comments on hfs_inode_setattr
  kernel: acct: fix duplicate word in comment
  fs: Replace user_access_{begin/end} by scoped user access
  readdir: Introduce dirent_size()
  coredump: add tracepoint for coredump events
  fs: remove do_sys_truncate
  fs: pass on FTRUNCATE_* flags to do_truncate
  fs: fix archiecture-specific compat_ftruncate64
  fs: remove stale and duplicate forward declarations
  init/initramfs.c: trivial fix: FSM -> Finite-state machine
  autofs: replace manual symlink buffer allocation in autofs_dir_symlink
  fs/mbcache: cancel shrink work before destroying the cache
  ...
 2026-04-13 14:20:11 -07:00
Linus Torvalds
b7d74ea0fd vfs-7.1-rc1.kino 
Please consider pulling these changes from the signed vfs-7.1-rc1.kino tag.
 
 Thanks!
 Christian
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Merge tag 'vfs-7.1-rc1.kino' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs i_ino updates from Christian Brauner:
 "For historical reasons, the inode->i_ino field is an unsigned long,
  which means that it's 32 bits on 32 bit architectures. This has caused
  a number of filesystems to implement hacks to hash a 64-bit identifier
  into a 32-bit field, and deprives us of a universal identifier field
  for an inode.

  This changes the inode->i_ino field from an unsigned long to a u64.
  This shouldn't make any material difference on 64-bit hosts, but
  32-bit hosts will see struct inode grow by at least 4 bytes. This
  could have effects on slabcache sizes and field alignment.

  The bulk of the changes are to format strings and tracepoints, since
  the kernel itself doesn't care that much about the i_ino field. The
  first patch changes some vfs function arguments, so check that one out
  carefully.

  With this change, we may be able to shrink some inode structures. For
  instance, struct nfs_inode has a fileid field that holds the 64-bit
  inode number. With this set of changes, that field could be
  eliminated. I'd rather leave that sort of cleanups for later just to
  keep this simple"

* tag 'vfs-7.1-rc1.kino' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  nilfs2: fix 64-bit division operations in nilfs_bmap_find_target_in_group()
  EVM: add comment describing why ino field is still unsigned long
  vfs: remove externs from fs.h on functions modified by i_ino widening
  treewide: fix missed i_ino format specifier conversions
  ext4: fix signed format specifier in ext4_load_inode trace event
  treewide: change inode->i_ino from unsigned long to u64
  nilfs2: widen trace event i_ino fields to u64
  f2fs: widen trace event i_ino fields to u64
  ext4: widen trace event i_ino fields to u64
  zonefs: widen trace event i_ino fields to u64
  hugetlbfs: widen trace event i_ino fields to u64
  ext2: widen trace event i_ino fields to u64
  cachefiles: widen trace event i_ino fields to u64
  vfs: widen trace event i_ino fields to u64
  net: change sock.sk_ino and sock_i_ino() to u64
  audit: widen ino fields to u64
  vfs: widen inode hash/lookup functions to u64
 2026-04-13 12:19:01 -07:00
Linus Torvalds
3383589700 vfs-7.1-rc1.directory 
Please consider pulling these changes from the signed vfs-7.1-rc1.directory tag.
 
 Thanks!
 Christian
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Merge tag 'vfs-7.1-rc1.directory' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs directory updates from Christian Brauner:
 "Recently 'start_creating', 'start_removing', 'start_renaming' and
  related interfaces were added which combine the locking and the
  lookup.

  At that time many callers were changed to use the new interfaces.
  However there are still an assortment of places out side of the core
  vfs where the directory is locked explictly, whether with inode_lock()
  or lock_rename() or similar. These were missed in the first pass for
  an assortment of uninteresting reasons.

  This addresses the remaining places where explicit locking is used,
  and changes them to use the new interfaces, or otherwise removes the
  explicit locking.

  The biggest changes are in overlayfs. The other changes are quite
  simple, though maybe the cachefiles changes is the least simple of
  those"

* tag 'vfs-7.1-rc1.directory' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  VFS: unexport lock_rename(), lock_rename_child(), unlock_rename()
  ovl: remove ovl_lock_rename_workdir()
  ovl: use is_subdir() for testing if one thing is a subdir of another
  ovl: change ovl_create_real() to get a new lock when re-opening created file.
  ovl: pass name buffer to ovl_start_creating_temp()
  cachefiles: change cachefiles_bury_object to use start_renaming_dentry()
  ovl: Simplify ovl_lookup_real_one()
  VFS: make lookup_one_qstr_excl() static.
  nfsd: switch purge_old() to use start_removing_noperm()
  selinux: Use simple_start_creating() / simple_done_creating()
  Apparmor: Use simple_start_creating() / simple_done_creating()
  libfs: change simple_done_creating() to use end_creating()
  VFS: move the start_dirop() kerndoc comment to before start_dirop()
  fs/proc: Don't lock root inode when creating "self" and "thread-self"
  VFS: note error returns in documentation for various lookup functions
 2026-04-13 10:24:33 -07:00
Dave Airlie
2232ba9c79 mm: add gpu active/reclaim per-node stat counters (v2) 
While discussing memcg intergration with gpu memory allocations,
it was pointed out that there was no numa/system counters for
GPU memory allocations.

With more integrated memory GPU server systems turning up, and
more requirements for memory tracking it seems we should start
closing the gap.

Add two counters to track GPU per-node system memory allocations.

The first is currently allocated to GPU objects, and the second
is for memory that is stored in GPU page pools that can be reclaimed,
by the shrinker.

Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Zi Yan <ziy@nvidia.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
 2026-04-08 06:52:47 +10:00
Johannes Weiner
b9ec0ed907 mm: vmalloc: streamline vmalloc memory accounting 
Use a vmstat counter instead of a custom, open-coded atomic. This has
the added benefit of making the data available per-node, and prepares
for cleaning up the memcg accounting as well.

Link: https://lkml.kernel.org/r/20260223160147.3792777-1-hannes@cmpxchg.org
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-04-05 13:53:04 -07:00
Mike Rapoport (Microsoft)
9a1d0c738b mm: rename my_zero_pfn() to zero_pfn() 
my_zero_pfn() is a silly name.

Rename zero_pfn variable to zero_page_pfn and my_zero_pfn() function to
zero_pfn().

While on it, move extern declarations of zero_page_pfn outside the
functions that use it and add a comment about what ZERO_PAGE is.

Link: https://lkml.kernel.org/r/20260211103141.3215197-3-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Magnus Lindholm <linmag7@gmail.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-04-05 13:53:01 -07:00
Jaime Saguillo Revilla
38d581ba76 proc: array: drop stale FIXME about RCU in task_sig() 
task_sig() already wraps the SigQ rlimit read in an explicit RCU read-side
critical section.  Drop the stale FIXME comment and keep using
task_ucounts() for the ucounts access.

No functional change.

Link: https://lkml.kernel.org/r/20260215124511.14227-1-jaime.saguillo@gmail.com
Signed-off-by: Jaime Saguillo Revilla <jaime.saguillo@gmail.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-03-27 21:19:32 -07:00
Christoph Hellwig
2ecd46d161
proc: rename proc_notify_change to proc_setattr 
Make the function name match the method that it implements.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260325063711.3298685-6-hch@lst.de
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2026-03-26 15:16:54 +01:00
Christoph Hellwig
690005b0b1
proc: rename proc_setattr to proc_nochmod_setattr 
What is currently proc_setattr is a special version added after the more
general procfs ->seattr in commit 6d76fa58b0 ("Don't allow chmod() on
the /proc/<pid>/ files").  Give it a name that reflects that to free the
proc_setattr name and better describe what is doing.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260325063711.3298685-5-hch@lst.de
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2026-03-26 15:16:54 +01:00
Jeff Layton
0b2600f81c
treewide: change inode->i_ino from unsigned long to u64 
On 32-bit architectures, unsigned long is only 32 bits wide, which
causes 64-bit inode numbers to be silently truncated. Several
filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that
exceed 32 bits, and this truncation can lead to inode number collisions
and other subtle bugs on 32-bit systems.

Change the type of inode->i_ino from unsigned long to u64 to ensure that
inode numbers are always represented as 64-bit values regardless of
architecture. Update all format specifiers treewide from %lu/%lx to
%llu/%llx to match the new type, along with corresponding local variable
types.

This is the bulk treewide conversion. Earlier patches in this series
handled trace events separately to allow trace field reordering for
better struct packing on 32-bit.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org
Acked-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2026-03-06 14:31:28 +01:00
NeilBrown
9ab6838984
fs/proc: Don't lock root inode when creating "self" and "thread-self" 
proc_setup_self() and proc_setup_thread_self() are only called from
proc_fill_super() which is before the filesystem is "live".  So there is
no need to lock the root directory when adding "self" and "thread-self".
This is clear from simple_fill_super() which provides similar
functionality for other filesystems and does not lock anything.

The locking is not harmful, except that it may be confusing to a reader.
As part of an effort to centralise all locking for directories for
name-based operations (prior to changing some locking rules), it is
simplest to remove the locking here.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20260224222542.3458677-3-neilb@ownmail.net
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2026-03-06 10:24:11 +01:00
Linus Torvalds
0e335a7745 vfs-7.0-rc2.fixes 
Please consider pulling these changes from the signed vfs-7.0-rc2.fixes tag.
 
 Thanks!
 Christian
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Merge tag 'vfs-7.0-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs fixes from Christian Brauner:

 - Fix an uninitialized variable in file_getattr().

   The flags_valid field wasn't initialized before calling
   vfs_fileattr_get(), triggering KMSAN uninit-value reports in fuse

 - Fix writeback wakeup and logging timeouts when DETECT_HUNG_TASK is
   not enabled.

   sysctl_hung_task_timeout_secs is 0 in that case causing spurious
   "waiting for writeback completion for more than 1 seconds" warnings

 - Fix a null-ptr-deref in do_statmount() when the mount is internal

 - Add missing kernel-doc description for the @private parameter in
   iomap_readahead()

 - Fix mount namespace creation to hold namespace_sem across the mount
   copy in create_new_namespace().

   The previous drop-and-reacquire pattern was fragile and failed to
   clean up mount propagation links if the real rootfs was a shared or
   dependent mount

 - Fix /proc mount iteration where m->index wasn't updated when
   m->show() overflows, causing a restart to repeatedly show the same
   mount entry in a rapidly expanding mount table

 - Return EFSCORRUPTED instead of ENOSPC in minix_new_inode() when the
   inode number is out of range

 - Fix unshare(2) when CLONE_NEWNS is set and current->fs isn't shared.

   copy_mnt_ns() received the live fs_struct so if a subsequent
   namespace creation failed the rollback would leave pwd and root
   pointing to detached mounts. Always allocate a new fs_struct when
   CLONE_NEWNS is requested

 - fserror bug fixes:

    - Remove the unused fsnotify_sb_error() helper now that all callers
      have been converted to fserror_report_metadata

    - Fix a lockdep splat in fserror_report() where igrab() takes
      inode::i_lock which can be held in IRQ context.

      Replace igrab() with a direct i_count bump since filesystems
      should not report inodes that are about to be freed or not yet
      exposed

 - Handle error pointer in procfs for try_lookup_noperm()

 - Fix an integer overflow in ep_loop_check_proc() where recursive calls
   returning INT_MAX would overflow when +1 is added, breaking the
   recursion depth check

 - Fix a misleading break in pidfs

* tag 'vfs-7.0-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  pidfs: avoid misleading break
  eventpoll: Fix integer overflow in ep_loop_check_proc()
  proc: Fix pointer error dereference
  fserror: fix lockdep complaint when igrabbing inode
  fsnotify: drop unused helper
  unshare: fix unshare_fs() handling
  minix: Correct errno in minix_new_inode
  namespace: fix proc mount iteration
  mount: hold namespace_sem across copy in create_new_namespace()
  iomap: Describe @private in iomap_readahead()
  statmount: Fix the null-ptr-deref in do_statmount()
  writeback: Fix wakeup and logging timeouts for !DETECT_HUNG_TASK
  fs: init flags_valid before calling vfs_fileattr_get
 2026-02-25 10:34:23 -08:00
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 2026-02-21 17:09:51 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types 
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
 2026-02-21 01:02:28 -08:00
Ethan Tidmore
f6a495484a
proc: Fix pointer error dereference 
The function try_lookup_noperm() can return an error pointer. Add check
for error pointer.

Detected by Smatch:
fs/proc/base.c:2148 proc_fill_cache() error:
'child' dereferencing possible ERR_PTR()

Fixes: 1df98b8bbc ("proc_fill_cache(): clean up, get rid of pointless find_inode_number() use")
Signed-off-by: Ethan Tidmore <ethantidmore06@gmail.com>
Link: https://patch.msgid.link/20260219221001.1117135-1-ethantidmore06@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2026-02-20 11:21:16 +01:00
Linus Torvalds
44331bd6a6 Three MM hotfixes, all three are cc:stable. 
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Merge tag 'mm-hotfixes-stable-2026-02-13-07-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM fixes from Andrew Morton:
 "Three MM hotfixes, all three are cc:stable"

* tag 'mm-hotfixes-stable-2026-02-13-07-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  procfs: fix possible double mmput() in do_procmap_query()
  mm/page_alloc: skip debug_check_no_{obj,locks}_freed with FPI_TRYLOCK
  mm/hugetlb: restore failed global reservations to subpool
 2026-02-13 12:13:27 -08:00
Andrii Nakryiko
61dc9f7767 procfs: fix possible double mmput() in do_procmap_query() 
When user provides incorrectly sized buffer for build ID for PROCMAP_QUERY
we return with -ENAMETOOLONG error.  After recent changes this condition
happens later, after we unlocked mmap_lock/per-VMA lock and did mmput(),
so original goto out is now wrong and will double-mmput() mm_struct.  Fix
by jumping further to clean up only vm_file and name_buf.

Link: https://lkml.kernel.org/r/20260210192738.3041609-1-andrii@kernel.org
Fixes: b5cbacd7f8 ("procfs: avoid fetching build ID while holding VMA lock")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reported-by: Ruikai Peng <ruikai@pwno.io>
Reported-by: Thomas Gleixner <tglx@kernel.org>
Tested-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Reported-by: syzbot+237b5b985b78c1da9600@syzkaller.appspotmail.com
Cc: Ruikai Peng <ruikai@pwno.io>
Closes: https://lkml.kernel.org/r/CAFD3drOJANTZPuyiqMdqpiRwOKnHwv5QgMNZghCDr-WxdiHvMg@mail.gmail.com
Closes: https://lore.kernel.org/all/698aaf3c.050a0220.3b3015.0088.GAE@google.com/T/#u
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-02-12 15:40:16 -08:00
Linus Torvalds
136114e0ab mm.git review status for linus..mm-nonmm-stable 
Total patches:       107
 Reviews/patch:       1.07
 Reviewed rate:       67%
 
 - The 2 patch series "ocfs2: give ocfs2 the ability to reclaim
   suballocator free bg" from Heming Zhao saves disk space by teaching
   ocfs2 to reclaim suballocator block group space.
 
 - The 4 patch series "Add ARRAY_END(), and use it to fix off-by-one
   bugs" from Alejandro Colomar adds the ARRAY_END() macro and uses it in
   various places.
 
 - The 2 patch series "vmcoreinfo: support VMCOREINFO_BYTES larger than
   PAGE_SIZE" from Pnina Feder makes the vmcore code future-safe, if
   VMCOREINFO_BYTES ever exceeds the page size.
 
 - The 7 patch series "kallsyms: Prevent invalid access when showing
   module buildid" from Petr Mladek cleans up kallsyms code related to
   module buildid and fixes an invalid access crash when printing
   backtraces.
 
 - The 3 patch series "Address page fault in
   ima_restore_measurement_list()" from Harshit Mogalapalli fixes a
   kexec-related crash that can occur when booting the second-stage kernel
   on x86.
 
 - The 6 patch series "kho: ABI headers and Documentation updates" from
   Mike Rapoport updates the kexec handover ABI documentation.
 
 - The 4 patch series "Align atomic storage" from Finn Thain adds the
   __aligned attribute to atomic_t and atomic64_t definitions to get
   natural alignment of both types on csky, m68k, microblaze, nios2,
   openrisc and sh.
 
 - The 2 patch series "kho: clean up page initialization logic" from
   Pratyush Yadav simplifies the page initialization logic in
   kho_restore_page().
 
 - The 6 patch series "Unload linux/kernel.h" from Yury Norov moves
   several things out of kernel.h and into more appropriate places.
 
 - The 7 patch series "don't abuse task_struct.group_leader" from Oleg
   Nesterov removes the usage of ->group_leader when it is "obviously
   unnecessary".
 
 - The 5 patch series "list private v2 & luo flb" from Pasha Tatashin
   adds some infrastructure improvements to the live update orchestrator.
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Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - "ocfs2: give ocfs2 the ability to reclaim suballocator free bg" saves
   disk space by teaching ocfs2 to reclaim suballocator block group
   space (Heming Zhao)

 - "Add ARRAY_END(), and use it to fix off-by-one bugs" adds the
   ARRAY_END() macro and uses it in various places (Alejandro Colomar)

 - "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE" makes
   the vmcore code future-safe, if VMCOREINFO_BYTES ever exceeds the
   page size (Pnina Feder)

 - "kallsyms: Prevent invalid access when showing module buildid" cleans
   up kallsyms code related to module buildid and fixes an invalid
   access crash when printing backtraces (Petr Mladek)

 - "Address page fault in ima_restore_measurement_list()" fixes a
   kexec-related crash that can occur when booting the second-stage
   kernel on x86 (Harshit Mogalapalli)

 - "kho: ABI headers and Documentation updates" updates the kexec
   handover ABI documentation (Mike Rapoport)

 - "Align atomic storage" adds the __aligned attribute to atomic_t and
   atomic64_t definitions to get natural alignment of both types on
   csky, m68k, microblaze, nios2, openrisc and sh (Finn Thain)

 - "kho: clean up page initialization logic" simplifies the page
   initialization logic in kho_restore_page() (Pratyush Yadav)

 - "Unload linux/kernel.h" moves several things out of kernel.h and into
   more appropriate places (Yury Norov)

 - "don't abuse task_struct.group_leader" removes the usage of
   ->group_leader when it is "obviously unnecessary" (Oleg Nesterov)

 - "list private v2 & luo flb" adds some infrastructure improvements to
   the live update orchestrator (Pasha Tatashin)

* tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits)
  watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency
  procfs: fix missing RCU protection when reading real_parent in do_task_stat()
  watchdog/softlockup: fix sample ring index wrap in need_counting_irqs()
  kcsan, compiler_types: avoid duplicate type issues in BPF Type Format
  kho: fix doc for kho_restore_pages()
  tests/liveupdate: add in-kernel liveupdate test
  liveupdate: luo_flb: introduce File-Lifecycle-Bound global state
  liveupdate: luo_file: Use private list
  list: add kunit test for private list primitives
  list: add primitives for private list manipulations
  delayacct: fix uapi timespec64 definition
  panic: add panic_force_cpu= parameter to redirect panic to a specific CPU
  netclassid: use thread_group_leader(p) in update_classid_task()
  RDMA/umem: don't abuse current->group_leader
  drm/pan*: don't abuse current->group_leader
  drm/amd: kill the outdated "Only the pthreads threading model is supported" checks
  drm/amdgpu: don't abuse current->group_leader
  android/binder: use same_thread_group(proc->tsk, current) in binder_mmap()
  android/binder: don't abuse current->group_leader
  kho: skip memoryless NUMA nodes when reserving scratch areas
  ...
 2026-02-12 12:13:01 -08:00
Linus Torvalds
4cff5c05e0 mm.git review status for linus..mm-stable 
Everything:
 
 Total patches:       325
 Reviews/patch:       1.39
 Reviewed rate:       72%
 
 Excluding DAMON:
 
 Total patches:       262
 Reviews/patch:       1.63
 Reviewed rate:       82%
 
 Excluding DAMON and zram:
 
 Total patches:       248
 Reviews/patch:       1.72
 Reviewed rate:       86%
 
 - The 14 patch series "powerpc/64s: do not re-activate batched TLB
   flush" from Alexander Gordeev makes arch_{enter|leave}_lazy_mmu_mode()
   nest properly.
 
   It adds a generic enter/leave layer and switches architectures to use
   it.  Various hacks were removed in the process.
 
 - The 7 patch series "zram: introduce compressed data writeback" from
   Richard Chang and Sergey Senozhatsky implements data compression for
   zram writeback.
 
 - The 8 patch series "mm: folio_zero_user: clear page ranges" from David
   Hildenbrand adds clearing of contiguous page ranges for hugepages.
   Large improvements during demand faulting are demonstrated.
 
 - The 2 patch series "memcg cleanups" from Chen Ridong tideis up some
   memcg code.
 
 - The 12 patch series "mm/damon: introduce {,max_}nr_snapshots and
   tracepoint for damos stats" from SeongJae Park improves DAMOS stat's
   provided information, deterministic control, and readability.
 
 - The 3 patch series "selftests/mm: hugetlb cgroup charging: robustness
   fixes" from Li Wang fixes a few issues in the hugetlb cgroup charging
   selftests.
 
 - The 5 patch series "Fix va_high_addr_switch.sh test failure - again"
   from Chunyu Hu addresses several issues in the va_high_addr_switch test.
 
 - The 5 patch series "mm/damon/tests/core-kunit: extend existing test
   scenarios" from Shu Anzai improves the KUnit test coverage for DAMON.
 
 - The 2 patch series "mm/khugepaged: fix dirty page handling for
   MADV_COLLAPSE" from Shivank Garg fixes a glitch in khugepaged which was
   causing madvise(MADV_COLLAPSE) to transiently return -EAGAIN.
 
 - The 29 patch series "arch, mm: consolidate hugetlb early reservation"
   from Mike Rapoport reworks and consolidates a pile of straggly code
   related to reservation of hugetlb memory from bootmem and creation of
   CMA areas for hugetlb.
 
 - The 9 patch series "mm: clean up anon_vma implementation" from Lorenzo
   Stoakes cleans up the anon_vma implementation in various ways.
 
 - The 3 patch series "tweaks for __alloc_pages_slowpath()" from
   Vlastimil Babka does a little streamlining of the page allocator's
   slowpath code.
 
 - The 8 patch series "memcg: separate private and public ID namespaces"
   from Shakeel Butt cleans up the memcg ID code and prevents the
   internal-only private IDs from being exposed to userspace.
 
 - The 6 patch series "mm: hugetlb: allocate frozen gigantic folio" from
   Kefeng Wang cleans up the allocation of frozen folios and avoids some
   atomic refcount operations.
 
 - The 11 patch series "mm/damon: advance DAMOS-based LRU sorting" from
   SeongJae Park improves DAMOS's movement of memory betewwn the active and
   inactive LRUs and adds auto-tuning of the ratio-based quotas and of
   monitoring intervals.
 
 - The 18 patch series "Support page table check on PowerPC" from Andrew
   Donnellan makes CONFIG_PAGE_TABLE_CHECK_ENFORCED work on powerpc.
 
 - The 3 patch series "nodemask: align nodes_and{,not} with underlying
   bitmap ops" from Yury Norov makes nodes_and() and nodes_andnot()
   propagate the return values from the underlying bit operations, enabling
   some cleanup in calling code.
 
 - The 5 patch series "mm/damon: hide kdamond and kdamond_lock from API
   callers" from SeongJae Park cleans up some DAMON internal interfaces.
 
 - The 4 patch series "mm/khugepaged: cleanups and scan limit fix" from
   Shivank Garg does some cleanup work in khupaged and fixes a scan limit
   accounting issue.
 
 - The 24 patch series "mm: balloon infrastructure cleanups" from David
   Hildenbrand goes to town on the balloon infrastructure and its page
   migration function.  Mainly cleanups, also some locking simplification.
 
 - The 2 patch series "mm/vmscan: add tracepoint and reason for
   kswapd_failures reset" from Jiayuan Chen adds additional tracepoints to
   the page reclaim code.
 
 - The 3 patch series "Replace wq users and add WQ_PERCPU to
   alloc_workqueue() users" from Marco Crivellari is part of Marco's
   kernel-wide migration from the legacy workqueue APIs over to the
   preferred unbound workqueues.
 
 - The 9 patch series "Various mm kselftests improvements/fixes" from
   Kevin Brodsky provides various unrelated improvements/fixes for the mm
   kselftests.
 
 - The 5 patch series "mm: accelerate gigantic folio allocation" from
   Kefeng Wang greatly speeds up gigantic folio allocation, mainly by
   avoiding unnecessary work in pfn_range_valid_contig().
 
 - The 5 patch series "selftests/damon: improve leak detection and wss
   estimation reliability" from SeongJae Park improves the reliability of
   two of the DAMON selftests.
 
 - The 8 patch series "mm/damon: cleanup kdamond, damon_call(), damos
   filter and DAMON_MIN_REGION" from SeongJae Park does some cleanup work
   in the core DAMON code.
 
 - The 8 patch series "Docs/mm/damon: update intro, modules, maintainer
   profile, and misc" from SeongJae Park performs maintenance work on the
   DAMON documentation.
 
 - The 10 patch series "mm: add and use vma_assert_stabilised() helper"
   from Lorenzo Stoakes refactors and cleans up the core VMA code.  The
   main aim here is to be able to use the mmap write lock's lockdep state
   to perform various assertions regarding the locking which the VMA code
   requires.
 
 - The 19 patch series "mm, swap: swap table phase II: unify swapin use"
   from Kairui Song removes some old swap code (swap cache bypassing and
   swap synchronization) which wasn't working very well.  Various other
   cleanups and simplifications were made.  The end result is a 20% speedup
   in one benchmark.
 
 - The 8 patch series "enable PT_RECLAIM on more 64-bit architectures"
   from Qi Zheng makes PT_RECLAIM available on 64-bit alpha, loongarch,
   mips, parisc, um,  Various cleanups were performed along the way.
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Merge tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - "powerpc/64s: do not re-activate batched TLB flush" makes
   arch_{enter|leave}_lazy_mmu_mode() nest properly (Alexander Gordeev)

   It adds a generic enter/leave layer and switches architectures to use
   it. Various hacks were removed in the process.

 - "zram: introduce compressed data writeback" implements data
   compression for zram writeback (Richard Chang and Sergey Senozhatsky)

 - "mm: folio_zero_user: clear page ranges" adds clearing of contiguous
   page ranges for hugepages. Large improvements during demand faulting
   are demonstrated (David Hildenbrand)

 - "memcg cleanups" tidies up some memcg code (Chen Ridong)

 - "mm/damon: introduce {,max_}nr_snapshots and tracepoint for damos
   stats" improves DAMOS stat's provided information, deterministic
   control, and readability (SeongJae Park)

 - "selftests/mm: hugetlb cgroup charging: robustness fixes" fixes a few
   issues in the hugetlb cgroup charging selftests (Li Wang)

 - "Fix va_high_addr_switch.sh test failure - again" addresses several
   issues in the va_high_addr_switch test (Chunyu Hu)

 - "mm/damon/tests/core-kunit: extend existing test scenarios" improves
   the KUnit test coverage for DAMON (Shu Anzai)

 - "mm/khugepaged: fix dirty page handling for MADV_COLLAPSE" fixes a
   glitch in khugepaged which was causing madvise(MADV_COLLAPSE) to
   transiently return -EAGAIN (Shivank Garg)

 - "arch, mm: consolidate hugetlb early reservation" reworks and
   consolidates a pile of straggly code related to reservation of
   hugetlb memory from bootmem and creation of CMA areas for hugetlb
   (Mike Rapoport)

 - "mm: clean up anon_vma implementation" cleans up the anon_vma
   implementation in various ways (Lorenzo Stoakes)

 - "tweaks for __alloc_pages_slowpath()" does a little streamlining of
   the page allocator's slowpath code (Vlastimil Babka)

 - "memcg: separate private and public ID namespaces" cleans up the
   memcg ID code and prevents the internal-only private IDs from being
   exposed to userspace (Shakeel Butt)

 - "mm: hugetlb: allocate frozen gigantic folio" cleans up the
   allocation of frozen folios and avoids some atomic refcount
   operations (Kefeng Wang)

 - "mm/damon: advance DAMOS-based LRU sorting" improves DAMOS's movement
   of memory betewwn the active and inactive LRUs and adds auto-tuning
   of the ratio-based quotas and of monitoring intervals (SeongJae Park)

 - "Support page table check on PowerPC" makes
   CONFIG_PAGE_TABLE_CHECK_ENFORCED work on powerpc (Andrew Donnellan)

 - "nodemask: align nodes_and{,not} with underlying bitmap ops" makes
   nodes_and() and nodes_andnot() propagate the return values from the
   underlying bit operations, enabling some cleanup in calling code
   (Yury Norov)

 - "mm/damon: hide kdamond and kdamond_lock from API callers" cleans up
   some DAMON internal interfaces (SeongJae Park)

 - "mm/khugepaged: cleanups and scan limit fix" does some cleanup work
   in khupaged and fixes a scan limit accounting issue (Shivank Garg)

 - "mm: balloon infrastructure cleanups" goes to town on the balloon
   infrastructure and its page migration function. Mainly cleanups, also
   some locking simplification (David Hildenbrand)

 - "mm/vmscan: add tracepoint and reason for kswapd_failures reset" adds
   additional tracepoints to the page reclaim code (Jiayuan Chen)

 - "Replace wq users and add WQ_PERCPU to alloc_workqueue() users" is
   part of Marco's kernel-wide migration from the legacy workqueue APIs
   over to the preferred unbound workqueues (Marco Crivellari)

 - "Various mm kselftests improvements/fixes" provides various unrelated
   improvements/fixes for the mm kselftests (Kevin Brodsky)

 - "mm: accelerate gigantic folio allocation" greatly speeds up gigantic
   folio allocation, mainly by avoiding unnecessary work in
   pfn_range_valid_contig() (Kefeng Wang)

 - "selftests/damon: improve leak detection and wss estimation
   reliability" improves the reliability of two of the DAMON selftests
   (SeongJae Park)

 - "mm/damon: cleanup kdamond, damon_call(), damos filter and
   DAMON_MIN_REGION" does some cleanup work in the core DAMON code
   (SeongJae Park)

 - "Docs/mm/damon: update intro, modules, maintainer profile, and misc"
   performs maintenance work on the DAMON documentation (SeongJae Park)

 - "mm: add and use vma_assert_stabilised() helper" refactors and cleans
   up the core VMA code. The main aim here is to be able to use the mmap
   write lock's lockdep state to perform various assertions regarding
   the locking which the VMA code requires (Lorenzo Stoakes)

 - "mm, swap: swap table phase II: unify swapin use" removes some old
   swap code (swap cache bypassing and swap synchronization) which
   wasn't working very well. Various other cleanups and simplifications
   were made. The end result is a 20% speedup in one benchmark (Kairui
   Song)

 - "enable PT_RECLAIM on more 64-bit architectures" makes PT_RECLAIM
   available on 64-bit alpha, loongarch, mips, parisc, and um. Various
   cleanups were performed along the way (Qi Zheng)

* tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (325 commits)
  mm/memory: handle non-split locks correctly in zap_empty_pte_table()
  mm: move pte table reclaim code to memory.c
  mm: make PT_RECLAIM depends on MMU_GATHER_RCU_TABLE_FREE
  mm: convert __HAVE_ARCH_TLB_REMOVE_TABLE to CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE config
  um: mm: enable MMU_GATHER_RCU_TABLE_FREE
  parisc: mm: enable MMU_GATHER_RCU_TABLE_FREE
  mips: mm: enable MMU_GATHER_RCU_TABLE_FREE
  LoongArch: mm: enable MMU_GATHER_RCU_TABLE_FREE
  alpha: mm: enable MMU_GATHER_RCU_TABLE_FREE
  mm: change mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h
  mm/damon/stat: remove __read_mostly from memory_idle_ms_percentiles
  zsmalloc: make common caches global
  mm: add SPDX id lines to some mm source files
  mm/zswap: use %pe to print error pointers
  mm/vmscan: use %pe to print error pointers
  mm/readahead: fix typo in comment
  mm: khugepaged: fix NR_FILE_PAGES and NR_SHMEM in collapse_file()
  mm: refactor vma_map_pages to use vm_insert_pages
  mm/damon: unify address range representation with damon_addr_range
  mm/cma: replace snprintf with strscpy in cma_new_area
  ...
 2026-02-12 11:32:37 -08:00
Jinliang Zheng
76149d5350 procfs: fix missing RCU protection when reading real_parent in do_task_stat() 
When reading /proc/[pid]/stat, do_task_stat() accesses task->real_parent
without proper RCU protection, which leads to:

  cpu 0                               cpu 1
  -----                               -----
  do_task_stat
    var = task->real_parent
                                      release_task
                                        call_rcu(delayed_put_task_struct)
    task_tgid_nr_ns(var)
      rcu_read_lock   <--- Too late to protect task->real_parent!
      task_pid_ptr    <--- UAF!
      rcu_read_unlock

This patch uses task_ppid_nr_ns() instead of task_tgid_nr_ns() to add
proper RCU protection for accessing task->real_parent.

Link: https://lkml.kernel.org/r/20260128083007.3173016-1-alexjlzheng@tencent.com
Fixes: 06fffb1267 ("do_task_stat: don't take rcu_read_lock()")
Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: ruippan <ruippan@tencent.com>
Cc: Usama Arif <usamaarif642@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-02-08 00:13:34 -08:00
Andrii Nakryiko
b5cbacd7f8 procfs: avoid fetching build ID while holding VMA lock 
Fix PROCMAP_QUERY to fetch optional build ID only after dropping mmap_lock
or per-VMA lock, whichever was used to lock VMA under question, to avoid
deadlock reported by syzbot:

 -> #1 (&mm->mmap_lock){++++}-{4:4}:
        __might_fault+0xed/0x170
        _copy_to_iter+0x118/0x1720
        copy_page_to_iter+0x12d/0x1e0
        filemap_read+0x720/0x10a0
        blkdev_read_iter+0x2b5/0x4e0
        vfs_read+0x7f4/0xae0
        ksys_read+0x12a/0x250
        do_syscall_64+0xcb/0xf80
        entry_SYSCALL_64_after_hwframe+0x77/0x7f

 -> #0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}:
        __lock_acquire+0x1509/0x26d0
        lock_acquire+0x185/0x340
        down_read+0x98/0x490
        blkdev_read_iter+0x2a7/0x4e0
        __kernel_read+0x39a/0xa90
        freader_fetch+0x1d5/0xa80
        __build_id_parse.isra.0+0xea/0x6a0
        do_procmap_query+0xd75/0x1050
        procfs_procmap_ioctl+0x7a/0xb0
        __x64_sys_ioctl+0x18e/0x210
        do_syscall_64+0xcb/0xf80
        entry_SYSCALL_64_after_hwframe+0x77/0x7f

 other info that might help us debug this:

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   rlock(&mm->mmap_lock);
                                lock(&sb->s_type->i_mutex_key#8);
                                lock(&mm->mmap_lock);
   rlock(&sb->s_type->i_mutex_key#8);

  *** DEADLOCK ***

This seems to be exacerbated (as we haven't seen these syzbot reports
before that) by the recent:

	777a8560fd ("lib/buildid: use __kernel_read() for sleepable context")

To make this safe, we need to grab file refcount while VMA is still locked, but
other than that everything is pretty straightforward. Internal build_id_parse()
API assumes VMA is passed, but it only needs the underlying file reference, so
just add another variant build_id_parse_file() that expects file passed
directly.

[akpm@linux-foundation.org: fix up kerneldoc]
Link: https://lkml.kernel.org/r/20260129215340.3742283-1-andrii@kernel.org
Fixes: ed5d583a88 ("fs/procfs: implement efficient VMA querying API for /proc/<pid>/maps")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reported-by: <syzbot+4e70c8e0a2017b432f7a@syzkaller.appspotmail.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Tested-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-02-05 14:10:00 -08:00
Randy Dunlap
24c776355f kernel.h: drop hex.h and update all hex.h users 
Remove <linux/hex.h> from <linux/kernel.h> and update all users/callers of
hex.h interfaces to directly #include <linux/hex.h> as part of the process
of putting kernel.h on a diet.

Removing hex.h from kernel.h means that 36K C source files don't have to
pay the price of parsing hex.h for the roughly 120 C source files that
need it.

This change has been build-tested with allmodconfig on most ARCHes.  Also,
all users/callers of <linux/hex.h> in the entire source tree have been
updated if needed (if not already #included).

Link: https://lkml.kernel.org/r/20251215005206.2362276-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-01-20 19:44:19 -08:00
Kevin Brodsky
0a096ab7a3 mm: introduce generic lazy_mmu helpers 
The implementation of the lazy MMU mode is currently entirely
arch-specific; core code directly calls arch helpers:
arch_{enter,leave}_lazy_mmu_mode().

We are about to introduce support for nested lazy MMU sections.  As things
stand we'd have to duplicate that logic in every arch implementing
lazy_mmu - adding to a fair amount of logic already duplicated across
lazy_mmu implementations.

This patch therefore introduces a new generic layer that calls the
existing arch_* helpers. Two pair of calls are introduced:

* lazy_mmu_mode_enable() ... lazy_mmu_mode_disable()
    This is the standard case where the mode is enabled for a given
    block of code by surrounding it with enable() and disable()
    calls.

* lazy_mmu_mode_pause() ... lazy_mmu_mode_resume()
    This is for situations where the mode is temporarily disabled
    by first calling pause() and then resume() (e.g. to prevent any
    batching from occurring in a critical section).

The documentation in <linux/pgtable.h> will be updated in a subsequent
patch.

No functional change should be introduced at this stage.  The
implementation of enable()/resume() and disable()/pause() is currently
identical, but nesting support will change that.

Most of the call sites have been updated using the following Coccinelle
script:

@@
@@
{
...
- arch_enter_lazy_mmu_mode();
+ lazy_mmu_mode_enable();
...
- arch_leave_lazy_mmu_mode();
+ lazy_mmu_mode_disable();
...
}

@@
@@
{
...
- arch_leave_lazy_mmu_mode();
+ lazy_mmu_mode_pause();
...
- arch_enter_lazy_mmu_mode();
+ lazy_mmu_mode_resume();
...
}

A couple of notes regarding x86:

* Xen is currently the only case where explicit handling is required
  for lazy MMU when context-switching. This is purely an
  implementation detail and using the generic lazy_mmu_mode_*
  functions would cause trouble when nesting support is introduced,
  because the generic functions must be called from the current task.
  For that reason we still use arch_leave() and arch_enter() there.

* x86 calls arch_flush_lazy_mmu_mode() unconditionally in a few
  places, but only defines it if PARAVIRT_XXL is selected, and we
  are removing the fallback in <linux/pgtable.h>. Add a new fallback
  definition to <asm/pgtable.h> to keep things building.

Link: https://lkml.kernel.org/r/20251215150323.2218608-8-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Yeoreum Yun <yeoreum.yun@arm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Hildenbrand (Red Hat) <david@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Juegren Gross <jgross@suse.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2026-01-20 19:24:33 -08:00
H. Peter Anvin
75beb7effa fs/proc: replace "__auto_type" with "const auto" 
Replace use of "__auto_type" in fs/proc/inode.c with "const auto".

Suggested-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Reviewed-by: Alexey Dobriyan <adobriyan@gmail.com>
 2025-12-08 15:32:15 -08:00
Linus Torvalds
509d3f4584 Significant patch series in this pull request: 
- The 6 patch series "panic: sys_info: Refactor and fix a potential
   issue" from Andy Shevchenko fixes a build issue and does some cleanup in
   ib/sys_info.c.
 
 - The 9 patch series "Implement mul_u64_u64_div_u64_roundup()" from
   David Laight enhances the 64-bit math code on behalf of a PWM driver and
   beefs up the test module for these library functions.
 
 - The 2 patch series "scripts/gdb/symbols: make BPF debug info available
   to GDB" from Ilya Leoshkevich makes BPF symbol names, sizes, and line
   numbers available to the GDB debugger.
 
 - The 4 patch series "Enable hung_task and lockup cases to dump system
   info on demand" from Feng Tang adds a sysctl which can be used to cause
   additional info dumping when the hung-task and lockup detectors fire.
 
 - The 6 patch series "lib/base64: add generic encoder/decoder, migrate
   users" from Kuan-Wei Chiu adds a general base64 encoder/decoder to lib/
   and migrates several users away from their private implementations.
 
 - The 2 patch series "rbree: inline rb_first() and rb_last()" from Eric
   Dumazet makes TCP a little faster.
 
 - The 9 patch series "liveupdate: Rework KHO for in-kernel users" from
   Pasha Tatashin reworks the KEXEC Handover interfaces in preparation for
   Live Update Orchestrator (LUO), and possibly for other future clients.
 
 - The 13 patch series "kho: simplify state machine and enable dynamic
   updates" from Pasha Tatashin increases the flexibility of KEXEC
   Handover.  Also preparation for LUO.
 
 - The 18 patch series "Live Update Orchestrator" from Pasha Tatashin is
   a major new feature targeted at cloud environments.  Quoting the [0/N]:
 
     This series introduces the Live Update Orchestrator, a kernel subsystem
     designed to facilitate live kernel updates using a kexec-based reboot.
     This capability is critical for cloud environments, allowing hypervisors
     to be updated with minimal downtime for running virtual machines.  LUO
     achieves this by preserving the state of selected resources, such as
     memory, devices and their dependencies, across the kernel transition.
 
     As a key feature, this series includes support for preserving memfd file
     descriptors, which allows critical in-memory data, such as guest RAM or
     any other large memory region, to be maintained in RAM across the kexec
     reboot.
 
   Mike Rappaport merits a mention here, for his extensive review and
   testing work.
 
 - The 3 patch series "kexec: reorganize kexec and kdump sysfs" from
   Sourabh Jain moves the kexec and kdump sysfs entries from /sys/kernel/
   to /sys/kernel/kexec/ and adds back-compatibility symlinks which can
   hopefully be removed one day.
 
 - The 2 patch series "kho: fixes for vmalloc restoration" from Mike
   Rapoport fixes a BUG which was being hit during KHO restoration of
   vmalloc() regions.
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Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko)
   fixes a build issue and does some cleanup in ib/sys_info.c

 - "Implement mul_u64_u64_div_u64_roundup()" (David Laight)
   enhances the 64-bit math code on behalf of a PWM driver and beefs up
   the test module for these library functions

 - "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich)
   makes BPF symbol names, sizes, and line numbers available to the GDB
   debugger

 - "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang)
   adds a sysctl which can be used to cause additional info dumping when
   the hung-task and lockup detectors fire

 - "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu)
   adds a general base64 encoder/decoder to lib/ and migrates several
   users away from their private implementations

 - "rbree: inline rb_first() and rb_last()" (Eric Dumazet)
   makes TCP a little faster

 - "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin)
   reworks the KEXEC Handover interfaces in preparation for Live Update
   Orchestrator (LUO), and possibly for other future clients

 - "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin)
   increases the flexibility of KEXEC Handover. Also preparation for LUO

 - "Live Update Orchestrator" (Pasha Tatashin)
   is a major new feature targeted at cloud environments. Quoting the
   cover letter:

      This series introduces the Live Update Orchestrator, a kernel
      subsystem designed to facilitate live kernel updates using a
      kexec-based reboot. This capability is critical for cloud
      environments, allowing hypervisors to be updated with minimal
      downtime for running virtual machines. LUO achieves this by
      preserving the state of selected resources, such as memory,
      devices and their dependencies, across the kernel transition.

      As a key feature, this series includes support for preserving
      memfd file descriptors, which allows critical in-memory data, such
      as guest RAM or any other large memory region, to be maintained in
      RAM across the kexec reboot.

   Mike Rappaport merits a mention here, for his extensive review and
   testing work.

 - "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain)
   moves the kexec and kdump sysfs entries from /sys/kernel/ to
   /sys/kernel/kexec/ and adds back-compatibility symlinks which can
   hopefully be removed one day

 - "kho: fixes for vmalloc restoration" (Mike Rapoport)
   fixes a BUG which was being hit during KHO restoration of vmalloc()
   regions

* tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits)
  calibrate: update header inclusion
  Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()"
  vmcoreinfo: track and log recoverable hardware errors
  kho: fix restoring of contiguous ranges of order-0 pages
  kho: kho_restore_vmalloc: fix initialization of pages array
  MAINTAINERS: TPM DEVICE DRIVER: update the W-tag
  init: replace simple_strtoul with kstrtoul to improve lpj_setup
  KHO: fix boot failure due to kmemleak access to non-PRESENT pages
  Documentation/ABI: new kexec and kdump sysfs interface
  Documentation/ABI: mark old kexec sysfs deprecated
  kexec: move sysfs entries to /sys/kernel/kexec
  test_kho: always print restore status
  kho: free chunks using free_page() instead of kfree()
  selftests/liveupdate: add kexec test for multiple and empty sessions
  selftests/liveupdate: add simple kexec-based selftest for LUO
  selftests/liveupdate: add userspace API selftests
  docs: add documentation for memfd preservation via LUO
  mm: memfd_luo: allow preserving memfd
  liveupdate: luo_file: add private argument to store runtime state
  mm: shmem: export some functions to internal.h
  ...
 2025-12-06 14:01:20 -08:00
Linus Torvalds
92fc1f16e2 Two fixes related to recent introduction of scoped_seqlock_read(): 
- Fix compiler build failures when a particular .config and
    compiler build options variant doesn't result in the
    expected removal of unused, catch-bugs portions of
    scoped_seqlock_read() by the inliner at build time,
    and cause a linker fail even in correct code.
 
  - Match read-locking order in do_task_stat() and
    do_io_accounting(). The inconsistency here was harmless
    but unnecessary.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fixes from Ingo Molnar:
 "Two fixes related to recent introduction of scoped_seqlock_read():

   - Fix compiler build failures when a particular .config and compiler
     build options variant doesn't result in the expected removal of
     unused, catch-bugs portions of scoped_seqlock_read() by the inliner
     at build time, and cause a linker fail even in correct code

   - Match read-locking order in do_task_stat() and do_io_accounting().
     The inconsistency here was harmless but unnecessary"

* tag 'locking-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  seqlock: Cure some more scoped_seqlock() optimization fails
  seqlock, procfs: Match scoped_seqlock_read() critical section vs. RCU ordering in do_task_stat() to do_io_accounting()
 2025-12-06 11:31:49 -08:00
Linus Torvalds
7cd122b552 Some filesystems use a kinda-sorta controlled dentry refcount leak to pin 
dentries of created objects in dcache (and undo it when removing those).
 Reference is grabbed and not released, but it's not actually _stored_
 anywhere.  That works, but it's hard to follow and verify; among other
 things, we have no way to tell _which_ of the increments is intended
 to be an unpaired one.  Worse, on removal we need to decide whether
 the reference had already been dropped, which can be non-trivial if
 that removal is on umount and we need to figure out if this dentry is
 pinned due to e.g. unlink() not done.  Usually that is handled by using
 kill_litter_super() as ->kill_sb(), but there are open-coded special
 cases of the same (consider e.g. /proc/self).
 
 Things get simpler if we introduce a new dentry flag (DCACHE_PERSISTENT)
 marking those "leaked" dentries.  Having it set claims responsibility
 for +1 in refcount.
 
 The end result this series is aiming for:
 
 * get these unbalanced dget() and dput() replaced with new primitives that
   would, in addition to adjusting refcount, set and clear persistency flag.
 * instead of having kill_litter_super() mess with removing the remaining
   "leaked" references (e.g. for all tmpfs files that hadn't been removed
   prior to umount), have the regular shrink_dcache_for_umount() strip
   DCACHE_PERSISTENT of all dentries, dropping the corresponding
   reference if it had been set.  After that kill_litter_super() becomes
   an equivalent of kill_anon_super().
 
 Doing that in a single step is not feasible - it would affect too many places
 in too many filesystems.  It has to be split into a series.
 
 This work has really started early in 2024; quite a few preliminary pieces
 have already gone into mainline.  This chunk is finally getting to the
 meat of that stuff - infrastructure and most of the conversions to it.
 
 Some pieces are still sitting in the local branches, but the bulk of
 that stuff is here.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull persistent dentry infrastructure and conversion from Al Viro:
 "Some filesystems use a kinda-sorta controlled dentry refcount leak to
  pin dentries of created objects in dcache (and undo it when removing
  those). A reference is grabbed and not released, but it's not actually
  _stored_ anywhere.

  That works, but it's hard to follow and verify; among other things, we
  have no way to tell _which_ of the increments is intended to be an
  unpaired one. Worse, on removal we need to decide whether the
  reference had already been dropped, which can be non-trivial if that
  removal is on umount and we need to figure out if this dentry is
  pinned due to e.g. unlink() not done. Usually that is handled by using
  kill_litter_super() as ->kill_sb(), but there are open-coded special
  cases of the same (consider e.g. /proc/self).

  Things get simpler if we introduce a new dentry flag
  (DCACHE_PERSISTENT) marking those "leaked" dentries. Having it set
  claims responsibility for +1 in refcount.

  The end result this series is aiming for:

   - get these unbalanced dget() and dput() replaced with new primitives
     that would, in addition to adjusting refcount, set and clear
     persistency flag.

   - instead of having kill_litter_super() mess with removing the
     remaining "leaked" references (e.g. for all tmpfs files that hadn't
     been removed prior to umount), have the regular
     shrink_dcache_for_umount() strip DCACHE_PERSISTENT of all dentries,
     dropping the corresponding reference if it had been set. After that
     kill_litter_super() becomes an equivalent of kill_anon_super().

  Doing that in a single step is not feasible - it would affect too many
  places in too many filesystems. It has to be split into a series.

  This work has really started early in 2024; quite a few preliminary
  pieces have already gone into mainline. This chunk is finally getting
  to the meat of that stuff - infrastructure and most of the conversions
  to it.

  Some pieces are still sitting in the local branches, but the bulk of
  that stuff is here"

* tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
  d_make_discardable(): warn if given a non-persistent dentry
  kill securityfs_recursive_remove()
  convert securityfs
  get rid of kill_litter_super()
  convert rust_binderfs
  convert nfsctl
  convert rpc_pipefs
  convert hypfs
  hypfs: swich hypfs_create_u64() to returning int
  hypfs: switch hypfs_create_str() to returning int
  hypfs: don't pin dentries twice
  convert gadgetfs
  gadgetfs: switch to simple_remove_by_name()
  convert functionfs
  functionfs: switch to simple_remove_by_name()
  functionfs: fix the open/removal races
  functionfs: need to cancel ->reset_work in ->kill_sb()
  functionfs: don't bother with ffs->ref in ffs_data_{opened,closed}()
  functionfs: don't abuse ffs_data_closed() on fs shutdown
  convert selinuxfs
  ...
 2025-12-05 14:36:21 -08:00
Linus Torvalds
7203ca412f Significant patch series in this merge are as follows: 
- The 10 patch series "__vmalloc()/kvmalloc() and no-block support" from
   Uladzislau Rezki reworks the vmalloc() code to support non-blocking
   allocations (GFP_ATOIC, GFP_NOWAIT).
 
 - The 2 patch series "ksm: fix exec/fork inheritance" from xu xin fixes
   a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not inherited
   across fork/exec.
 
 - The 4 patch series "mm/zswap: misc cleanup of code and documentations"
   from SeongJae Park does some light maintenance work on the zswap code.
 
 - The 5 patch series "mm/page_owner: add debugfs files 'show_handles'
   and 'show_stacks_handles'" from Mauricio Faria de Oliveira enhances the
   /sys/kernel/debug/page_owner debug feature.  It adds unique identifiers
   to differentiate the various stack traces so that userspace monitoring
   tools can better match stack traces over time.
 
 - The 2 patch series "mm/page_alloc: pcp->batch cleanups" from Joshua
   Hahn makes some minor alterations to the page allocator's per-cpu-pages
   feature.
 
 - The 2 patch series "Improve UFFDIO_MOVE scalability by removing
   anon_vma lock" from Lokesh Gidra addresses a scalability issue in
   userfaultfd's UFFDIO_MOVE operation.
 
 - The 2 patch series "kasan: cleanups for kasan_enabled() checks" from
   Sabyrzhan Tasbolatov performs some cleanup in the KASAN code.
 
 - The 2 patch series "drivers/base/node: fold node register and
   unregister functions" from Donet Tom cleans up the NUMA node handling
   code a little.
 
 - The 4 patch series "mm: some optimizations for prot numa" from Kefeng
   Wang provides some cleanups and small optimizations to the NUMA
   allocation hinting code.
 
 - The 5 patch series "mm/page_alloc: Batch callers of
   free_pcppages_bulk" from Joshua Hahn addresses long lock hold times at
   boot on large machines.  These were causing (harmless) softlockup
   warnings.
 
 - The 2 patch series "optimize the logic for handling dirty file folios
   during reclaim" from Baolin Wang removes some now-unnecessary work from
   page reclaim.
 
 - The 10 patch series "mm/damon: allow DAMOS auto-tuned for per-memcg
   per-node memory usage" from SeongJae Park enhances the DAMOS auto-tuning
   feature.
 
 - The 2 patch series "mm/damon: fixes for address alignment issues in
   DAMON_LRU_SORT and DAMON_RECLAIM" from Quanmin Yan fixes DAMON_LRU_SORT
   and DAMON_RECLAIM with certain userspace configuration.
 
 - The 15 patch series "expand mmap_prepare functionality, port more
   users" from Lorenzo Stoakes enhances the new(ish)
   file_operations.mmap_prepare() method and ports additional callsites
   from the old ->mmap() over to ->mmap_prepare().
 
 - The 8 patch series "Fix stale IOTLB entries for kernel address space"
   from Lu Baolu fixes a bug (and possible security issue on non-x86) in
   the IOMMU code.  In some situations the IOMMU could be left hanging onto
   a stale kernel pagetable entry.
 
 - The 4 patch series "mm/huge_memory: cleanup __split_unmapped_folio()"
   from Wei Yang cleans up and optimizes the folio splitting code.
 
 - The 5 patch series "mm, swap: misc cleanup and bugfix" from Kairui
   Song implements some cleanups and a minor fix in the swap discard code.
 
 - The 8 patch series "mm/damon: misc documentation fixups" from SeongJae
   Park does as advertised.
 
 - The 9 patch series "mm/damon: support pin-point targets removal" from
   SeongJae Park permits userspace to remove a specific monitoring target
   in the middle of the current targets list.
 
 - The 2 patch series "mm: MISC follow-up patches for linux/pgalloc.h"
   from Harry Yoo implements a couple of cleanups related to mm header file
   inclusion.
 
 - The 2 patch series "mm/swapfile.c: select swap devices of default
   priority round robin" from Baoquan He improves the selection of swap
   devices for NUMA machines.
 
 - The 3 patch series "mm: Convert memory block states (MEM_*) macros to
   enums" from Israel Batista changes the memory block labels from macros
   to enums so they will appear in kernel debug info.
 
 - The 3 patch series "ksm: perform a range-walk to jump over holes in
   break_ksm" from Pedro Demarchi Gomes addresses an inefficiency when KSM
   unmerges an address range.
 
 - The 22 patch series "mm/damon/tests: fix memory bugs in kunit tests"
   from SeongJae Park fixes leaks and unhandled malloc() failures in DAMON
   userspace unit tests.
 
 - The 2 patch series "some cleanups for pageout()" from Baolin Wang
   cleans up a couple of minor things in the page scanner's
   writeback-for-eviction code.
 
 - The 2 patch series "mm/hugetlb: refactor sysfs/sysctl interfaces" from
   Hui Zhu moves hugetlb's sysfs/sysctl handling code into a new file.
 
 - The 9 patch series "introduce VM_MAYBE_GUARD and make it sticky" from
   Lorenzo Stoakes makes the VMA guard regions available in /proc/pid/smaps
   and improves the mergeability of guarded VMAs.
 
 - The 2 patch series "mm: perform guard region install/remove under VMA
   lock" from Lorenzo Stoakes reduces mmap lock contention for callers
   performing VMA guard region operations.
 
 - The 2 patch series "vma_start_write_killable" from Matthew Wilcox
   starts work in permitting applications to be killed when they are
   waiting on a read_lock on the VMA lock.
 
 - The 11 patch series "mm/damon/tests: add more tests for online
   parameters commit" from SeongJae Park adds additional userspace testing
   of DAMON's "commit" feature.
 
 - The 9 patch series "mm/damon: misc cleanups" from SeongJae Park does
   that.
 
 - The 2 patch series "make VM_SOFTDIRTY a sticky VMA flag" from Lorenzo
   Stoakes addresses the possible loss of a VMA's VM_SOFTDIRTY flag when
   that VMA is merged with another.
 
 - The 16 patch series "mm: support device-private THP" from Balbir Singh
   introduces support for Transparent Huge Page (THP) migration in zone
   device-private memory.
 
 - The 3 patch series "Optimize folio split in memory failure" from Zi
   Yan optimizes folio split operations in the memory failure code.
 
 - The 2 patch series "mm/huge_memory: Define split_type and consolidate
   split support checks" from Wei Yang provides some more cleanups in the
   folio splitting code.
 
 - The 16 patch series "mm: remove is_swap_[pte, pmd]() + non-swap
   entries, introduce leaf entries" from Lorenzo Stoakes cleans up our
   handling of pagetable leaf entries by introducing the concept of
   'software leaf entries', of type softleaf_t.
 
 - The 4 patch series "reparent the THP split queue" from Muchun Song
   reparents the THP split queue to its parent memcg.  This is in
   preparation for addressing the long-standing "dying memcg" problem,
   wherein dead memcg's linger for too long, consuming memory resources.
 
 - The 3 patch series "unify PMD scan results and remove redundant
   cleanup" from Wei Yang does a little cleanup in the hugepage collapse
   code.
 
 - The 6 patch series "zram: introduce writeback bio batching" from
   Sergey Senozhatsky improves zram writeback efficiency by introducing
   batched bio writeback support.
 
 - The 4 patch series "memcg: cleanup the memcg stats interfaces" from
   Shakeel Butt cleans up our handling of the interrupt safety of some
   memcg stats.
 
 - The 4 patch series "make vmalloc gfp flags usage more apparent" from
   Vishal Moola cleans up vmalloc's handling of incoming GFP flags.
 
 - The 6 patch series "mm: Add soft-dirty and uffd-wp support for RISC-V"
   from Chunyan Zhang teches soft dirty and userfaultfd write protect
   tracking to use RISC-V's Svrsw60t59b extension.
 
 - The 5 patch series "mm: swap: small fixes and comment cleanups" from
   Youngjun Park fixes a small bug and cleans up some of the swap code.
 
 - The 4 patch series "initial work on making VMA flags a bitmap" from
   Lorenzo Stoakes starts work on converting the vma struct's flags to a
   bitmap, so we stop running out of them, especially on 32-bit.
 
 - The 2 patch series "mm/swapfile: fix and cleanup swap list iterations"
   from Youngjun Park addresses a possible bug in the swap discard code and
   cleans things up a little.
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Merge tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

  "__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki)
     Rework the vmalloc() code to support non-blocking allocations
     (GFP_ATOIC, GFP_NOWAIT)

  "ksm: fix exec/fork inheritance" (xu xin)
     Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not
     inherited across fork/exec

  "mm/zswap: misc cleanup of code and documentations" (SeongJae Park)
     Some light maintenance work on the zswap code

  "mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira)
     Enhance the /sys/kernel/debug/page_owner debug feature by adding
     unique identifiers to differentiate the various stack traces so
     that userspace monitoring tools can better match stack traces over
     time

  "mm/page_alloc: pcp->batch cleanups" (Joshua Hahn)
     Minor alterations to the page allocator's per-cpu-pages feature

  "Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra)
     Address a scalability issue in userfaultfd's UFFDIO_MOVE operation

  "kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov)

  "drivers/base/node: fold node register and unregister functions" (Donet Tom)
     Clean up the NUMA node handling code a little

  "mm: some optimizations for prot numa" (Kefeng Wang)
     Cleanups and small optimizations to the NUMA allocation hinting
     code

  "mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn)
     Address long lock hold times at boot on large machines. These were
     causing (harmless) softlockup warnings

  "optimize the logic for handling dirty file folios during reclaim" (Baolin Wang)
     Remove some now-unnecessary work from page reclaim

  "mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park)
     Enhance the DAMOS auto-tuning feature

  "mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan)
     Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace
     configuration

  "expand mmap_prepare functionality, port more users" (Lorenzo Stoakes)
     Enhance the new(ish) file_operations.mmap_prepare() method and port
     additional callsites from the old ->mmap() over to ->mmap_prepare()

  "Fix stale IOTLB entries for kernel address space" (Lu Baolu)
     Fix a bug (and possible security issue on non-x86) in the IOMMU
     code. In some situations the IOMMU could be left hanging onto a
     stale kernel pagetable entry

  "mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang)
     Clean up and optimize the folio splitting code

  "mm, swap: misc cleanup and bugfix" (Kairui Song)
     Some cleanups and a minor fix in the swap discard code

  "mm/damon: misc documentation fixups" (SeongJae Park)

  "mm/damon: support pin-point targets removal" (SeongJae Park)
     Permit userspace to remove a specific monitoring target in the
     middle of the current targets list

  "mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo)
     A couple of cleanups related to mm header file inclusion

  "mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He)
     improve the selection of swap devices for NUMA machines

  "mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista)
     Change the memory block labels from macros to enums so they will
     appear in kernel debug info

  "ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes)
     Address an inefficiency when KSM unmerges an address range

  "mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park)
     Fix leaks and unhandled malloc() failures in DAMON userspace unit
     tests

  "some cleanups for pageout()" (Baolin Wang)
     Clean up a couple of minor things in the page scanner's
     writeback-for-eviction code

  "mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu)
     Move hugetlb's sysfs/sysctl handling code into a new file

  "introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes)
     Make the VMA guard regions available in /proc/pid/smaps and
     improves the mergeability of guarded VMAs

  "mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes)
     Reduce mmap lock contention for callers performing VMA guard region
     operations

  "vma_start_write_killable" (Matthew Wilcox)
     Start work on permitting applications to be killed when they are
     waiting on a read_lock on the VMA lock

  "mm/damon/tests: add more tests for online parameters commit" (SeongJae Park)
     Add additional userspace testing of DAMON's "commit" feature

  "mm/damon: misc cleanups" (SeongJae Park)

  "make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes)
     Address the possible loss of a VMA's VM_SOFTDIRTY flag when that
     VMA is merged with another

  "mm: support device-private THP" (Balbir Singh)
     Introduce support for Transparent Huge Page (THP) migration in zone
     device-private memory

  "Optimize folio split in memory failure" (Zi Yan)

  "mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang)
     Some more cleanups in the folio splitting code

  "mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes)
     Clean up our handling of pagetable leaf entries by introducing the
     concept of 'software leaf entries', of type softleaf_t

  "reparent the THP split queue" (Muchun Song)
     Reparent the THP split queue to its parent memcg. This is in
     preparation for addressing the long-standing "dying memcg" problem,
     wherein dead memcg's linger for too long, consuming memory
     resources

  "unify PMD scan results and remove redundant cleanup" (Wei Yang)
     A little cleanup in the hugepage collapse code

  "zram: introduce writeback bio batching" (Sergey Senozhatsky)
     Improve zram writeback efficiency by introducing batched bio
     writeback support

  "memcg: cleanup the memcg stats interfaces" (Shakeel Butt)
     Clean up our handling of the interrupt safety of some memcg stats

  "make vmalloc gfp flags usage more apparent" (Vishal Moola)
     Clean up vmalloc's handling of incoming GFP flags

  "mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang)
     Teach soft dirty and userfaultfd write protect tracking to use
     RISC-V's Svrsw60t59b extension

  "mm: swap: small fixes and comment cleanups" (Youngjun Park)
     Fix a small bug and clean up some of the swap code

  "initial work on making VMA flags a bitmap" (Lorenzo Stoakes)
     Start work on converting the vma struct's flags to a bitmap, so we
     stop running out of them, especially on 32-bit

  "mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park)
     Address a possible bug in the swap discard code and clean things
     up a little

[ This merge also reverts commit ebb9aeb980 ("vfio/nvgrace-gpu:
  register device memory for poison handling") because it looks
  broken to me, I've asked for clarification   - Linus ]

* tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
  mm: fix vma_start_write_killable() signal handling
  mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate
  mm/swapfile: fix list iteration when next node is removed during discard
  fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling
  mm/kfence: add reboot notifier to disable KFENCE on shutdown
  memcg: remove inc/dec_lruvec_kmem_state helpers
  selftests/mm/uffd: initialize char variable to Null
  mm: fix DEBUG_RODATA_TEST indentation in Kconfig
  mm: introduce VMA flags bitmap type
  tools/testing/vma: eliminate dependency on vma->__vm_flags
  mm: simplify and rename mm flags function for clarity
  mm: declare VMA flags by bit
  zram: fix a spelling mistake
  mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity
  mm/vmscan: skip increasing kswapd_failures when reclaim was boosted
  pagemap: update BUDDY flag documentation
  mm: swap: remove scan_swap_map_slots() references from comments
  mm: swap: change swap_alloc_slow() to void
  mm, swap: remove redundant comment for read_swap_cache_async
  mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational
  ...
 2025-12-05 13:52:43 -08:00
Ingo Molnar
24bc5ea5c0 seqlock, procfs: Match scoped_seqlock_read() critical section vs. RCU ordering in do_task_stat() to do_io_accounting() 
There's two patterns of taking the RCU read-lock and the
sig->stats_lock read-seqlock in do_task_stat() and
do_io_accounting(), with a different ordering:

	# do_io_accounting():

	guard(rcu)();
	scoped_seqlock_read (&sig->stats_lock, ss_lock_irqsave) {

	# do_task_stat():

	scoped_seqlock_read (&sig->stats_lock, ss_lock_irqsave) {
	...
			rcu_read_lock();

The ordering is RCU-read+seqlock_read in the first
case, seqlock_read+RCU-read in the second case.

While technically these read locks can be taken in any order,
nevertheless it's good practice to use the more intrusive lock
on the inside (which is the IRQs-off section in this case),
and reduces head-scratching during review when done consistently,
so let's use the do_io_accounting() pattern in do_task_stat().

This will also reduce irqs-off latencies in do_task_stat() a tiny bit.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: https://patch.msgid.link/aS6rwnaPbHFCdHp1@gmail.com
 2025-12-02 11:21:07 +01:00
Linus Torvalds
b53440f8e5 Locking updates for v6.19: 
Mutexes:
 
  - Redo __mutex_init() to reduce generated code size
    (Sebastian Andrzej Siewior)
 
 Seqlocks:
 
  - Introduce scoped_seqlock_read() (Peter Zijlstra)
 
  - Change thread_group_cputime() to use scoped_seqlock_read()
    (Oleg Nesterov)
 
  - Change do_task_stat() to use scoped_seqlock_read()
    (Oleg Nesterov)
 
  - Change do_io_accounting() to use scoped_seqlock_read()
    (Oleg Nesterov)
 
  - Fix the incorrect documentation of read_seqbegin_or_lock() /
    need_seqretry() (Oleg Nesterov)
 
  - Allow KASAN to fail optimizing (Peter Zijlstra)
 
 Local lock updates:
 
  - Fix all kernel-doc warnings (Randy Dunlap)
 
  - Add the <linux/local_lock*.h> headers to MAINTAINERS
    (Sebastian Andrzej Siewior)
 
  - Reduce the risk of shadowing via s/l/__l/ and s/tl/__tl/
    (Vincent Mailhol)
 
 Lock debugging:
 
  - spinlock/debug: Fix data-race in do_raw_write_lock
    (Alexander Sverdlin)
 
 Atomic primitives infrastructure:
 
  - atomic: Skip alignment check for try_cmpxchg() old arg
    (Arnd Bergmann)
 
 Rust runtime integration:
 
  - sync: atomic: Enable generated Atomic<T> usage (Boqun Feng)
 
  - sync: atomic: Implement Debug for Atomic<Debug> (Boqun Feng)
 
  - debugfs: Remove Rust native atomics and replace them with
    Linux versions (Boqun Feng)
 
  - debugfs: Implement Reader for Mutex<T> only when T is Unpin
    (Boqun Feng)
 
  - lock: guard: Add T: Unpin bound to DerefMut (Daniel Almeida)
 
  - lock: Pin the inner data (Daniel Almeida)
 
  - lock: Add a Pin<&mut T> accessor (Daniel Almeida)
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
 "Mutexes:

   - Redo __mutex_init() to reduce generated code size (Sebastian
     Andrzej Siewior)

  Seqlocks:

   - Introduce scoped_seqlock_read() (Peter Zijlstra)

   - Change thread_group_cputime() to use scoped_seqlock_read() (Oleg
     Nesterov)

   - Change do_task_stat() to use scoped_seqlock_read() (Oleg Nesterov)

   - Change do_io_accounting() to use scoped_seqlock_read() (Oleg
     Nesterov)

   - Fix the incorrect documentation of read_seqbegin_or_lock() /
     need_seqretry() (Oleg Nesterov)

   - Allow KASAN to fail optimizing (Peter Zijlstra)

  Local lock updates:

   - Fix all kernel-doc warnings (Randy Dunlap)

   - Add the <linux/local_lock*.h> headers to MAINTAINERS (Sebastian
     Andrzej Siewior)

   - Reduce the risk of shadowing via s/l/__l/ and s/tl/__tl/ (Vincent
     Mailhol)

  Lock debugging:

   - spinlock/debug: Fix data-race in do_raw_write_lock (Alexander
     Sverdlin)

  Atomic primitives infrastructure:

   - atomic: Skip alignment check for try_cmpxchg() old arg (Arnd
     Bergmann)

  Rust runtime integration:

   - sync: atomic: Enable generated Atomic<T> usage (Boqun Feng)

   - sync: atomic: Implement Debug for Atomic<Debug> (Boqun Feng)

   - debugfs: Remove Rust native atomics and replace them with Linux
     versions (Boqun Feng)

   - debugfs: Implement Reader for Mutex<T> only when T is Unpin (Boqun
     Feng)

   - lock: guard: Add T: Unpin bound to DerefMut (Daniel Almeida)

   - lock: Pin the inner data (Daniel Almeida)

   - lock: Add a Pin<&mut T> accessor (Daniel Almeida)"

* tag 'locking-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/local_lock: Fix all kernel-doc warnings
  locking/local_lock: s/l/__l/ and s/tl/__tl/ to reduce the risk of shadowing
  locking/local_lock: Add the <linux/local_lock*.h> headers to MAINTAINERS
  locking/mutex: Redo __mutex_init() to reduce generated code size
  rust: debugfs: Replace the usage of Rust native atomics
  rust: sync: atomic: Implement Debug for Atomic<Debug>
  rust: sync: atomic: Make Atomic*Ops pub(crate)
  seqlock: Allow KASAN to fail optimizing
  rust: debugfs: Implement Reader for Mutex<T> only when T is Unpin
  seqlock: Change do_io_accounting() to use scoped_seqlock_read()
  seqlock: Change do_task_stat() to use scoped_seqlock_read()
  seqlock: Change thread_group_cputime() to use scoped_seqlock_read()
  seqlock: Introduce scoped_seqlock_read()
  documentation: seqlock: fix the wrong documentation of read_seqbegin_or_lock/need_seqretry
  atomic: Skip alignment check for try_cmpxchg() old arg
  rust: lock: Add a Pin<&mut T> accessor
  rust: lock: Pin the inner data
  rust: lock: guard: Add T: Unpin bound to DerefMut
  locking/spinlock/debug: Fix data-race in do_raw_write_lock
 2025-12-01 19:50:58 -08:00
Lorenzo Stoakes
12f0cd3933 fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling 
make_uffd_wp_huge_pte() should return after handling a huge_pte_none()
pte.

Link: https://lkml.kernel.org/r/66178124-ebdf-4e23-b8ca-ed3eb8030c81@lucifer.local
Fixes: 03bfbc3ad6 ("mm: remove is_hugetlb_entry_[migration, hwpoisoned]()")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Closes: https://lkml.kernel.org/r/dc483db3-be4d-45f7-8b40-a28f5d8f5738@suse.cz
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-29 10:41:10 -08:00
Lorenzo Stoakes
2b6a3f061f mm: declare VMA flags by bit 
Patch series "initial work on making VMA flags a bitmap", v3.

We are in the rather silly situation that we are running out of VMA flags
as they are currently limited to a system word in size.

This leads to absurd situations where we limit features to 64-bit
architectures only because we simply do not have the ability to add a flag
for 32-bit ones.

This is very constraining and leads to hacks or, in the worst case, simply
an inability to implement features we want for entirely arbitrary reasons.

This also of course gives us something of a Y2K type situation in mm where
we might eventually exhaust all of the VMA flags even on 64-bit systems.

This series lays the groundwork for getting away from this limitation by
establishing VMA flags as a bitmap whose size we can increase in future
beyond 64 bits if required.

This is necessarily a highly iterative process given the extensive use of
VMA flags throughout the kernel, so we start by performing basic steps.

Firstly, we declare VMA flags by bit number rather than by value,
retaining the VM_xxx fields but in terms of these newly introduced
VMA_xxx_BIT fields.

While we are here, we use sparse annotations to ensure that, when dealing
with VMA bit number parameters, we cannot be passed values which are not
declared as such - providing some useful type safety.

We then introduce an opaque VMA flag type, much like the opaque mm_struct
flag type introduced in commit bb6525f2f8 ("mm: add bitmap mm->flags
field"), which we establish in union with vma->vm_flags (but still set at
system word size meaning there is no functional or data type size change).

We update the vm_flags_xxx() helpers to use this new bitmap, introducing
sensible helpers to do so.

This series lays the foundation for further work to expand the use of
bitmap VMA flags and eventually eliminate these arbitrary restrictions.


This patch (of 4):

In order to lay the groundwork for VMA flags being a bitmap rather than a
system word in size, we need to be able to consistently refer to VMA flags
by bit number rather than value.

Take this opportunity to do so in an enum which we which is additionally
useful for tooling to extract metadata from.

This additionally makes it very clear which bits are being used for what
at a glance.

We use the VMA_ prefix for the bit values as it is logical to do so since
these reference VMAs.  We consistently suffix with _BIT to make it clear
what the values refer to.

We declare bit values even when the flags that use them would not be
enabled by config options as this is simply clearer and clearly defines
what bit numbers are used for what, at no additional cost.

We declare a sparse-bitwise type vma_flag_t which ensures that users can't
pass around invalid VMA flags by accident and prepares for future work
towards VMA flags being a bitmap where we want to ensure bit values are
type safe.

To make life easier, we declare some macro helpers - DECLARE_VMA_BIT()
allows us to avoid duplication in the enum bit number declarations (and
maintaining the sparse __bitwise attribute), and INIT_VM_FLAG() is used to
assist with declaration of flags.

Unfortunately we can't declare both in the enum, as we run into issue with
logic in the kernel requiring that flags are preprocessor definitions, and
additionally we cannot have a macro which declares another macro so we
must define each flag macro directly.

Additionally, update the VMA userland testing vma_internal.h header to
include these changes.

We also have to fix the parameters to the vma_flag_*_atomic() functions
since VMA_MAYBE_GUARD_BIT is now of type vma_flag_t and sparse will
complain otherwise.

We have to update some rather silly if-deffery found in mm/task_mmu.c
which would otherwise break.

Finally, we update the rust binding helper as now it cannot auto-detect
the flags at all.

Link: https://lkml.kernel.org/r/cover.1764064556.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/3a35e5a0bcfa00e84af24cbafc0653e74deda64a.1764064556.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Acked-by: Alice Ryhl <aliceryhl@google.com>	[rust]
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Björn Roy Baron <bjorn3_gh@protonmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Gary Guo <gary@garyguo.net>
Cc: Gregory Price <gourry@gourry.net>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Trevor Gross <tmgross@umich.edu>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-29 10:41:08 -08:00
Andrew Morton
bc947af677 Merge branch 'mm-hotfixes-stable' into mm-nonmm-stable in order to be able 
to merge "kho: make debugfs interface optional" into mm-nonmm-stable.
 2025-11-27 14:17:02 -08:00
Chunyan Zhang
277a1ae387 mm: softdirty: add pgtable_supports_soft_dirty() 
Patch series "mm: Add soft-dirty and uffd-wp support for RISC-V", v15.

This patchset adds support for Svrsw60t59b [1] extension which is ratified
now, also add soft dirty and userfaultfd write protect tracking for
RISC-V.

The patches 1 and 2 add macros to allow architectures to define their own
checks if the soft-dirty / uffd_wp PTE bits are available, in other words
for RISC-V, the Svrsw60t59b extension is supported on which device the
kernel is running.  Also patch1-2 are removing "ifdef
CONFIG_MEM_SOFT_DIRTY" "ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP" and "ifdef
CONFIG_PTE_MARKER_UFFD_WP" in favor of checks which if not overridden by
the architecture, no change in behavior is expected.

This patchset has been tested with kselftest mm suite in which soft-dirty,
madv_populate, test_unmerge_uffd_wp, and uffd-unit-tests run and pass, and
no regressions are observed in any of the other tests.


This patch (of 6):

Some platforms can customize the PTE PMD entry soft-dirty bit making it
unavailable even if the architecture provides the resource.

Add an API which architectures can define their specific implementations
to detect if soft-dirty bit is available on which device the kernel is
running.

This patch is removing "ifdef CONFIG_MEM_SOFT_DIRTY" in favor of
pgtable_supports_soft_dirty() checks that defaults to
IS_ENABLED(CONFIG_MEM_SOFT_DIRTY), if not overridden by the architecture,
no change in behavior is expected.

We make sure to never set VM_SOFTDIRTY if !pgtable_supports_soft_dirty(),
so we will never run into VM_SOFTDIRTY checks.

[lorenzo.stoakes@oracle.com: fix VMA selftests]
  Link: https://lkml.kernel.org/r/dac6ddfe-773a-43d5-8f69-021b9ca4d24b@lucifer.local
Link: https://lkml.kernel.org/r/20251113072806.795029-1-zhangchunyan@iscas.ac.cn
Link: https://lkml.kernel.org/r/20251113072806.795029-2-zhangchunyan@iscas.ac.cn
Link: https://github.com/riscv-non-isa/riscv-iommu/pull/543 [1]
Signed-off-by: Chunyan Zhang <zhangchunyan@iscas.ac.cn>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Conor Dooley <conor@kernel.org>
Cc: Deepak Gupta <debug@rivosinc.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Andrew Jones <ajones@ventanamicro.com>
Cc: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-24 15:08:54 -08:00
Lorenzo Stoakes
93976a2034 mm: eliminate further swapops predicates 
Having converted so much of the code base to software leaf entries, we can
mop up some remaining cases.

We replace is_pfn_swap_entry(), pfn_swap_entry_to_page(),
is_writable_device_private_entry(), is_device_exclusive_entry(),
is_migration_entry(), is_writable_migration_entry(),
is_readable_migration_entry(), swp_offset_pfn() and pfn_swap_entry_folio()
with softleaf equivalents.

No functional change intended.

Link: https://lkml.kernel.org/r/956bc9c031604811c0070d2f4bf2f1373f230213.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-24 15:08:52 -08:00
Lorenzo Stoakes
03bfbc3ad6 mm: remove is_hugetlb_entry_[migration, hwpoisoned]() 
We do not need to have explicit helper functions for these, it adds a
level of confusion and indirection when we can simply use software leaf
entry logic here instead and spell out the special huge_pte_none() case we
must consider.

No functional change intended.

Link: https://lkml.kernel.org/r/0e92d6924d3de88cd014ce1c53e20edc08fc152e.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-24 15:08:51 -08:00
Lorenzo Stoakes
9ff30bb9ab mm: remove non_swap_entry() and use softleaf helpers instead 
There is simply no need for the hugely confusing concept of 'non-swap'
swap entries now we have the concept of softleaf entries and relevant
softleaf_xxx() helpers.

Adjust all callers to use these instead and remove non_swap_entry()
altogether.

No functional change intended.

Link: https://lkml.kernel.org/r/2562093f37f4a9cffea0447058014485eb50aaaf.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-24 15:08:51 -08:00
Lorenzo Stoakes
0ac881efe1 mm: replace pmd_to_swp_entry() with softleaf_from_pmd() 
Introduce softleaf_from_pmd() to do the equivalent operation for PMDs that
softleaf_from_pte() fulfils, and cascade changes through code base
accordingly, introducing helpers as necessary.

We are then able to eliminate pmd_to_swp_entry(),
is_pmd_migration_entry(), is_pmd_device_private_entry() and
is_pmd_non_present_folio_entry().

This further establishes the use of leaf operations throughout the code
base and further establishes the foundations for eliminating
is_swap_pmd().

No functional change intended.

[lorenzo.stoakes@oracle.com: check writable, not readable/writable, per Vlastimil]
  Link: https://lkml.kernel.org/r/cd97b6ec-00f9-45a4-9ae0-8f009c212a94@lucifer.local
Link: https://lkml.kernel.org/r/3fb431699639ded8fdc63d2210aa77a38c8891f1.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: SeongJae Park <sj@kernel.org>\
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-24 15:08:51 -08:00
Lorenzo Stoakes
aa62204cb6 mm: avoid unnecessary use of is_swap_pmd() 
PMD 'non-swap' swap entries are currently used for PMD-level migration
entries and device private entries.

To add to the confusion in this terminology we use is_swap_pmd() in an
inconsistent way similar to how is_swap_pte() was being used - sometimes
adopting the convention that !pmd_none(), !pmd_present() implies PMD 'swap'
entry, sometimes not.

This patch handles the low-hanging fruit of cases where we can simply
substitute other predicates for is_swap_pmd().

No functional change intended.

Link: https://lkml.kernel.org/r/8a1704b36a009c18032d5bea4cb68e71448fbbe5.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-24 15:08:51 -08:00
Lorenzo Stoakes
de4d6c9491 fs/proc/task_mmu: refactor pagemap_pmd_range() 
Separate out THP logic so we can drop an indentation level and reduce the
amount of noise in this function.

We add pagemap_pmd_range_thp() for this purpose.

While we're here, convert the VM_BUG_ON() to a VM_WARN_ON_ONCE() at the
same time.

No functional change intended.

Link: https://lkml.kernel.org/r/f9ce7f3bb57e3627288225e23f2498cc5315f5ab.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-24 15:08:51 -08:00
Lorenzo Stoakes
fb888710e2 mm: avoid unnecessary uses of is_swap_pte() 
There's an established convention in the kernel that we treat PTEs as
containing swap entries (and the unfortunately named non-swap swap
entries) should they be neither empty (i.e.  pte_none() evaluating true)
nor present (i.e.  pte_present() evaluating true).

However, there is some inconsistency in how this is applied, as we also
have the is_swap_pte() helper which explicitly performs this check:

	/* check whether a pte points to a swap entry */
	static inline int is_swap_pte(pte_t pte)
	{
		return !pte_none(pte) && !pte_present(pte);
	}

As this represents a predicate, and it's logical to assume that in order
to establish that a PTE entry can correctly be manipulated as a
swap/non-swap entry, this predicate seems as if it must first be checked.

But we instead, we far more often utilise the established convention of
checking pte_none() / pte_present() before operating on entries as if they
were swap/non-swap.

This patch works towards correcting this inconsistency by removing all
uses of is_swap_pte() where we are already in a position where we perform
pte_none()/pte_present() checks anyway or otherwise it is clearly logical
to do so.

We also take advantage of the fact that pte_swp_uffd_wp() is only set on
swap entries.

Additionally, update comments referencing to is_swap_pte() and
non_swap_entry().

No functional change intended.

Link: https://lkml.kernel.org/r/17fd6d7f46a846517fd455fadd640af47fcd7c55.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-24 15:08:50 -08:00
Lorenzo Stoakes
68aa2fdbf5 mm: introduce leaf entry type and use to simplify leaf entry logic 
The kernel maintains leaf page table entries which contain either:

The kernel maintains leaf page table entries which contain either:

 - Nothing ('none' entries)
 - Present entries*
 - Everything else that will cause a fault which the kernel handles

* Present entries are either entries the hardware can navigate without page
  fault or special cases like NUMA hint protnone or PMD with cleared
  present bit which contain hardware-valid entries modulo the present bit.

In the 'everything else' group we include swap entries, but we also
include a number of other things such as migration entries, device private
entries and marker entries.

Unfortunately this 'everything else' group expresses everything through a
swp_entry_t type, and these entries are referred to swap entries even
though they may well not contain a...  swap entry.

This is compounded by the rather mind-boggling concept of a non-swap swap
entry (checked via non_swap_entry()) and the means by which we twist and
turn to satisfy this.

This patch lays the foundation for reducing this confusion.

We refer to 'everything else' as a 'software-define leaf entry' or
'softleaf'.  for short And in fact we scoop up the 'none' entries into
this concept also so we are left with:

- Present entries.
- Softleaf entries (which may be empty).

This allows for radical simplification across the board - one can simply
convert any leaf page table entry to a leaf entry via softleaf_from_pte().

If the entry is present, we return an empty leaf entry, so it is assumed
the caller is aware that they must differentiate between the two
categories of page table entries, checking for the former via
pte_present().

As a result, we can eliminate a number of places where we would otherwise
need to use predicates to see if we can proceed with leaf page table entry
conversion and instead just go ahead and do it unconditionally.

We do so where we can, adjusting surrounding logic as necessary to
integrate the new softleaf_t logic as far as seems reasonable at this
stage.

We typedef swp_entry_t to softleaf_t for the time being until the
conversion can be complete, meaning everything remains compatible
regardless of which type is used.  We will eventually remove swp_entry_t
when the conversion is complete.

We introduce a new header file to keep things clear - leafops.h - this
imports swapops.h so can direct replace swapops imports without issue, and
we do so in all the files that require it.

Additionally, add new leafops.h file to core mm maintainers entry.

Link: https://lkml.kernel.org/r/c879383aac77d96a03e4d38f7daba893cd35fc76.1762812360.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Wei Xu <weixugc@google.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-24 15:08:50 -08:00
zhang jiao
14954cd190 fs/proc/page: remove unused KPMBITS 
KPMBITS is never referenced in the code. Just remove it.

Link: https://lkml.kernel.org/r/20251106010735.1603-1-zhangjiao2@cmss.chinamobile.com
Signed-off-by: zhang jiao <zhangjiao2@cmss.chinamobile.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Liu Ye <liuye@kylinos.cn>
Cc: Luiz Capitulino <luizcap@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-20 14:03:42 -08:00
Lorenzo Stoakes
5dba5cc2e0 mm: introduce VM_MAYBE_GUARD and make visible in /proc/$pid/smaps 
Patch series "introduce VM_MAYBE_GUARD and make it sticky", v4.

Currently, guard regions are not visible to users except through
/proc/$pid/pagemap, with no explicit visibility at the VMA level.

This makes the feature less useful, as it isn't entirely apparent which
VMAs may have these entries present, especially when performing actions
which walk through memory regions such as those performed by CRIU.

This series addresses this issue by introducing the VM_MAYBE_GUARD flag
which fulfils this role, updating the smaps logic to display an entry for
these.

The semantics of this flag are that a guard region MAY be present if set
(we cannot be sure, as we can't efficiently track whether an
MADV_GUARD_REMOVE finally removes all the guard regions in a VMA) - but if
not set the VMA definitely does NOT have any guard regions present.

It's problematic to establish this flag without further action, because
that means that VMAs with guard regions in them become non-mergeable with
adjacent VMAs for no especially good reason.

To work around this, this series also introduces the concept of 'sticky'
VMA flags - that is flags which:

a. if set in one VMA and not in another still permit those VMAs to be
   merged (if otherwise compatible).

b. When they are merged, the resultant VMA must have the flag set.

The VMA logic is updated to propagate these flags correctly.

Additionally, VM_MAYBE_GUARD being an explicit VMA flag allows us to solve
an issue with file-backed guard regions - previously these established an
anon_vma object for file-backed mappings solely to have vma_needs_copy()
correctly propagate guard region mappings to child processes.

We introduce a new flag alias VM_COPY_ON_FORK (which currently only
specifies VM_MAYBE_GUARD) and update vma_needs_copy() to check explicitly
for this flag and to copy page tables if it is present, which resolves
this issue.

Additionally, we add the ability for allow-listed VMA flags to be
atomically writable with only mmap/VMA read locks held.

The only flag we allow so far is VM_MAYBE_GUARD, which we carefully ensure
does not cause any races by being allowed to do so.

This allows us to maintain guard region installation as a read-locked
operation and not endure the overhead of obtaining a write lock here.

Finally we introduce extensive VMA userland tests to assert that the
sticky VMA logic behaves correctly as well as guard region self tests to
assert that smaps visibility is correctly implemented.


This patch (of 9):

Currently, if a user needs to determine if guard regions are present in a
range, they have to scan all VMAs (or have knowledge of which ones might
have guard regions).

Since commit 8e2f2aeb8b ("fs/proc/task_mmu: add guard region bit to
pagemap") and the related commit a516403787 ("fs/proc: extend the
PAGEMAP_SCAN ioctl to report guard regions"), users can use either
/proc/$pid/pagemap or the PAGEMAP_SCAN functionality to perform this
operation at a virtual address level.

This is not ideal, and it gives no visibility at a /proc/$pid/smaps level
that guard regions exist in ranges.

This patch remedies the situation by establishing a new VMA flag,
VM_MAYBE_GUARD, to indicate that a VMA may contain guard regions (it is
uncertain because we cannot reasonably determine whether a
MADV_GUARD_REMOVE call has removed all of the guard regions in a VMA, and
additionally VMAs may change across merge/split).

We utilise 0x800 for this flag which makes it available to 32-bit
architectures also, a flag that was previously used by VM_DENYWRITE, which
was removed in commit 8d0920bde5 ("mm: remove VM_DENYWRITE") and hasn't
bee reused yet.

We also update the smaps logic and documentation to identify these VMAs.

Another major use of this functionality is that we can use it to identify
that we ought to copy page tables on fork.

We do not actually implement usage of this flag in mm/madvise.c yet as we
need to allow some VMA flags to be applied atomically under mmap/VMA read
lock in order to avoid the need to acquire a write lock for this purpose.

Link: https://lkml.kernel.org/r/cover.1763460113.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/cf8ef821eba29b6c5b5e138fffe95d6dcabdedb9.1763460113.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-20 13:43:58 -08:00
Ryan Roberts
9ac09bb9fe mm: consistently use current->mm in mm_get_unmapped_area() 
mm_get_unmapped_area() is a wrapper around arch_get_unmapped_area() /
arch_get_unmapped_area_topdown(), both of which search current->mm for
some free space.  Neither take an mm_struct - they implicitly operate on
current->mm.

But the wrapper takes an mm_struct and uses it to decide whether to search
bottom up or top down.  All callers pass in current->mm for this, so
everything is working consistently.  But it feels like an accident waiting
to happen; eventually someone will call that function with a different mm,
expecting to find free space in it, but what gets returned is free space
in the current mm.

So let's simplify by removing the parameter and have the wrapper use
current->mm to decide which end to start at.  Now everything is consistent
and self-documenting.

Link: https://lkml.kernel.org/r/20251003155306.2147572-1-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Dev Jain <dev.jain@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-16 17:27:57 -08:00
Al Viro
23cbc7a795 procfs: make /self and /thread_self dentries persistent 
... and there's no need to remember those pointers anywhere - ->kill_sb()
no longer needs to bother since kill_anon_super() will take care of
them anyway and proc_pid_readdir() only wants the inumbers, which
we had in a couple of static variables all along.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 2025-11-16 01:35:02 -05:00
Wei Yang
895b4c0c79 fs/proc: fix uaf in proc_readdir_de() 
Pde is erased from subdir rbtree through rb_erase(), but not set the node
to EMPTY, which may result in uaf access.  We should use RB_CLEAR_NODE()
set the erased node to EMPTY, then pde_subdir_next() will return NULL to
avoid uaf access.

We found an uaf issue while using stress-ng testing, need to run testcase
getdent and tun in the same time.  The steps of the issue is as follows:

1) use getdent to traverse dir /proc/pid/net/dev_snmp6/, and current
   pde is tun3;

2) in the [time windows] unregister netdevice tun3 and tun2, and erase
   them from rbtree.  erase tun3 first, and then erase tun2.  the
   pde(tun2) will be released to slab;

3) continue to getdent process, then pde_subdir_next() will return
   pde(tun2) which is released, it will case uaf access.

CPU 0                                      |    CPU 1
-------------------------------------------------------------------------
traverse dir /proc/pid/net/dev_snmp6/      |   unregister_netdevice(tun->dev)   //tun3 tun2
sys_getdents64()                           |
  iterate_dir()                            |
    proc_readdir()                         |
      proc_readdir_de()                    |     snmp6_unregister_dev()
        pde_get(de);                       |       proc_remove()
        read_unlock(&proc_subdir_lock);    |         remove_proc_subtree()
                                           |           write_lock(&proc_subdir_lock);
        [time window]                      |           rb_erase(&root->subdir_node, &parent->subdir);
                                           |           write_unlock(&proc_subdir_lock);
        read_lock(&proc_subdir_lock);      |
        next = pde_subdir_next(de);        |
        pde_put(de);                       |
        de = next;    //UAF                |

rbtree of dev_snmp6
                        |
                    pde(tun3)
                     /    \
                  NULL  pde(tun2)

Link: https://lkml.kernel.org/r/20251025024233.158363-1-albin_yang@163.com
Signed-off-by: Wei Yang <albinwyang@tencent.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: wangzijie <wangzijie1@honor.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-11-09 21:19:43 -08:00
Oleg Nesterov
795aab353d seqlock: Change do_io_accounting() to use scoped_seqlock_read() 
To simplify the code and make it more readable.

[peterz: change to new interface]
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
 2025-10-21 12:31:57 +02:00
Oleg Nesterov
b76f72bea2 seqlock: Change do_task_stat() to use scoped_seqlock_read() 
To simplify the code and make it more readable.

[peterz: change to new interface]
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
 2025-10-21 12:31:57 +02:00
Linus Torvalds
e406d57be7 Patch series in this pull request: 
- The 3 patch series "ida: Remove the ida_simple_xxx() API" from
   Christophe Jaillet completes the removal of this legacy IDR API.
 
 - The 9 patch series "panic: introduce panic status function family"
   from Jinchao Wang provides a number of cleanups to the panic code and
   its various helpers, which were rather ad-hoc and scattered all over the
   place.
 
 - The 5 patch series "tools/delaytop: implement real-time keyboard
   interaction support" from Fan Yu adds a few nice user-facing usability
   changes to the delaytop monitoring tool.
 
 - The 3 patch series "efi: Fix EFI boot with kexec handover (KHO)" from
   Evangelos Petrongonas fixes a panic which was happening with the
   combination of EFI and KHO.
 
 - The 2 patch series "Squashfs: performance improvement and a sanity
   check" from Phillip Lougher teaches squashfs's lseek() about
   SEEK_DATA/SEEK_HOLE.  A mere 150x speedup was measured for a well-chosen
   microbenchmark.
 
 - Plus another 50-odd singleton patches all over the place.
 -----BEGIN PGP SIGNATURE-----
 
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Merge tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - "ida: Remove the ida_simple_xxx() API" from Christophe Jaillet
   completes the removal of this legacy IDR API

 - "panic: introduce panic status function family" from Jinchao Wang
   provides a number of cleanups to the panic code and its various
   helpers, which were rather ad-hoc and scattered all over the place

 - "tools/delaytop: implement real-time keyboard interaction support"
   from Fan Yu adds a few nice user-facing usability changes to the
   delaytop monitoring tool

 - "efi: Fix EFI boot with kexec handover (KHO)" from Evangelos
   Petrongonas fixes a panic which was happening with the combination of
   EFI and KHO

 - "Squashfs: performance improvement and a sanity check" from Phillip
   Lougher teaches squashfs's lseek() about SEEK_DATA/SEEK_HOLE. A mere
   150x speedup was measured for a well-chosen microbenchmark

 - plus another 50-odd singleton patches all over the place

* tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (75 commits)
  Squashfs: reject negative file sizes in squashfs_read_inode()
  kallsyms: use kmalloc_array() instead of kmalloc()
  MAINTAINERS: update Sibi Sankar's email address
  Squashfs: add SEEK_DATA/SEEK_HOLE support
  Squashfs: add additional inode sanity checking
  lib/genalloc: fix device leak in of_gen_pool_get()
  panic: remove CONFIG_PANIC_ON_OOPS_VALUE
  ocfs2: fix double free in user_cluster_connect()
  checkpatch: suppress strscpy warnings for userspace tools
  cramfs: fix incorrect physical page address calculation
  kernel: prevent prctl(PR_SET_PDEATHSIG) from racing with parent process exit
  Squashfs: fix uninit-value in squashfs_get_parent
  kho: only fill kimage if KHO is finalized
  ocfs2: avoid extra calls to strlen() after ocfs2_sprintf_system_inode_name()
  kernel/sys.c: fix the racy usage of task_lock(tsk->group_leader) in sys_prlimit64() paths
  sched/task.h: fix the wrong comment on task_lock() nesting with tasklist_lock
  coccinelle: platform_no_drv_owner: handle also built-in drivers
  coccinelle: of_table: handle SPI device ID tables
  lib/decompress: use designated initializers for struct compress_format
  efi: support booting with kexec handover (KHO)
  ...
 2025-10-02 18:44:54 -07:00
Linus Torvalds
8804d970fa Summary of significant series in this pull request: 
- The 3 patch series "mm, swap: improve cluster scan strategy" from
   Kairui Song improves performance and reduces the failure rate of swap
   cluster allocation.
 
 - The 4 patch series "support large align and nid in Rust allocators"
   from Vitaly Wool permits Rust allocators to set NUMA node and large
   alignment when perforning slub and vmalloc reallocs.
 
 - The 2 patch series "mm/damon/vaddr: support stat-purpose DAMOS" from
   Yueyang Pan extend DAMOS_STAT's handling of the DAMON operations sets
   for virtual address spaces for ops-level DAMOS filters.
 
 - The 3 patch series "execute PROCMAP_QUERY ioctl under per-vma lock"
   from Suren Baghdasaryan reduces mmap_lock contention during reads of
   /proc/pid/maps.
 
 - The 2 patch series "mm/mincore: minor clean up for swap cache
   checking" from Kairui Song performs some cleanup in the swap code.
 
 - The 11 patch series "mm: vm_normal_page*() improvements" from David
   Hildenbrand provides code cleanup in the pagemap code.
 
 - The 5 patch series "add persistent huge zero folio support" from
   Pankaj Raghav provides a block layer speedup by optionalls making the
   huge_zero_pagepersistent, instead of releasing it when its refcount
   falls to zero.
 
 - The 3 patch series "kho: fixes and cleanups" from Mike Rapoport adds a
   few touchups to the recently added Kexec Handover feature.
 
 - The 10 patch series "mm: make mm->flags a bitmap and 64-bit on all
   arches" from Lorenzo Stoakes turns mm_struct.flags into a bitmap.  To
   end the constant struggle with space shortage on 32-bit conflicting with
   64-bit's needs.
 
 - The 2 patch series "mm/swapfile.c and swap.h cleanup" from Chris Li
   cleans up some swap code.
 
 - The 7 patch series "selftests/mm: Fix false positives and skip
   unsupported tests" from Donet Tom fixes a few things in our selftests
   code.
 
 - The 7 patch series "prctl: extend PR_SET_THP_DISABLE to only provide
   THPs when advised" from David Hildenbrand "allows individual processes
   to opt-out of THP=always into THP=madvise, without affecting other
   workloads on the system".
 
   It's a long story - the [1/N] changelog spells out the considerations.
 
 - The 11 patch series "Add and use memdesc_flags_t" from Matthew Wilcox
   gets us started on the memdesc project.  Please see
   https://kernelnewbies.org/MatthewWilcox/Memdescs and
   https://blogs.oracle.com/linux/post/introducing-memdesc.
 
 - The 3 patch series "Tiny optimization for large read operations" from
   Chi Zhiling improves the efficiency of the pagecache read path.
 
 - The 5 patch series "Better split_huge_page_test result check" from Zi
   Yan improves our folio splitting selftest code.
 
 - The 2 patch series "test that rmap behaves as expected" from Wei Yang
   adds some rmap selftests.
 
 - The 3 patch series "remove write_cache_pages()" from Christoph Hellwig
   removes that function and converts its two remaining callers.
 
 - The 2 patch series "selftests/mm: uffd-stress fixes" from Dev Jain
   fixes some UFFD selftests issues.
 
 - The 3 patch series "introduce kernel file mapped folios" from Boris
   Burkov introduces the concept of "kernel file pages".  Using these
   permits btrfs to account its metadata pages to the root cgroup, rather
   than to the cgroups of random inappropriate tasks.
 
 - The 2 patch series "mm/pageblock: improve readability of some
   pageblock handling" from Wei Yang provides some readability improvements
   to the page allocator code.
 
 - The 11 patch series "mm/damon: support ARM32 with LPAE" from SeongJae
   Park teaches DAMON to understand arm32 highmem.
 
 - The 4 patch series "tools: testing: Use existing atomic.h for
   vma/maple tests" from Brendan Jackman performs some code cleanups and
   deduplication under tools/testing/.
 
 - The 2 patch series "maple_tree: Fix testing for 32bit compiles" from
   Liam Howlett fixes a couple of 32-bit issues in
   tools/testing/radix-tree.c.
 
 - The 2 patch series "kasan: unify kasan_enabled() and remove
   arch-specific implementations" from Sabyrzhan Tasbolatov moves KASAN
   arch-specific initialization code into a common arch-neutral
   implementation.
 
 - The 3 patch series "mm: remove zpool" from Johannes Weiner removes
   zspool - an indirection layer which now only redirects to a single thing
   (zsmalloc).
 
 - The 2 patch series "mm: task_stack: Stack handling cleanups" from
   Pasha Tatashin makes a couple of cleanups in the fork code.
 
 - The 37 patch series "mm: remove nth_page()" from David Hildenbrand
   makes rather a lot of adjustments at various nth_page() callsites,
   eventually permitting the removal of that undesirable helper function.
 
 - The 2 patch series "introduce kasan.write_only option in hw-tags" from
   Yeoreum Yun creates a KASAN read-only mode for ARM, using that
   architecture's memory tagging feature.  It is felt that a read-only mode
   KASAN is suitable for use in production systems rather than debug-only.
 
 - The 3 patch series "mm: hugetlb: cleanup hugetlb folio allocation"
   from Kefeng Wang does some tidying in the hugetlb folio allocation code.
 
 - The 12 patch series "mm: establish const-correctness for pointer
   parameters" from Max Kellermann makes quite a number of the MM API
   functions more accurate about the constness of their arguments.  This
   was getting in the way of subsystems (in this case CEPH) when they
   attempt to improving their own const/non-const accuracy.
 
 - The 7 patch series "Cleanup free_pages() misuse" from Vishal Moola
   fixes a number of code sites which were confused over when to use
   free_pages() vs __free_pages().
 
 - The 3 patch series "Add Rust abstraction for Maple Trees" from Alice
   Ryhl makes the mapletree code accessible to Rust.  Required by nouveau
   and by its forthcoming successor: the new Rust Nova driver.
 
 - The 2 patch series "selftests/mm: split_huge_page_test:
   split_pte_mapped_thp improvements" from David Hildenbrand adds a fix and
   some cleanups to the thp selftesting code.
 
 - The 14 patch series "mm, swap: introduce swap table as swap cache
   (phase I)" from Chris Li and Kairui Song is the first step along the
   path to implementing "swap tables" - a new approach to swap allocation
   and state tracking which is expected to yield speed and space
   improvements.  This patchset itself yields a 5-20% performance benefit
   in some situations.
 
 - The 3 patch series "Some ptdesc cleanups" from Matthew Wilcox utilizes
   the new memdesc layer to clean up the ptdesc code a little.
 
 - The 3 patch series "Fix va_high_addr_switch.sh test failure" from
   Chunyu Hu fixes some issues in our 5-level pagetable selftesting code.
 
 - The 2 patch series "Minor fixes for memory allocation profiling" from
   Suren Baghdasaryan addresses a couple of minor issues in relatively new
   memory allocation profiling feature.
 
 - The 3 patch series "Small cleanups" from Matthew Wilcox has a few
   cleanups in preparation for more memdesc work.
 
 - The 2 patch series "mm/damon: add addr_unit for DAMON_LRU_SORT and
   DAMON_RECLAIM" from Quanmin Yan makes some changes to DAMON in
   furtherance of supporting arm highmem.
 
 - The 2 patch series "selftests/mm: Add -Wunreachable-code and fix
   warnings" from Muhammad Anjum adds that compiler check to selftests code
   and fixes the fallout, by removing dead code.
 
 - The 10 patch series "Improvements to Victim Process Thawing and OOM
   Reaper Traversal Order" from zhongjinji makes a number of improvements
   in the OOM killer: mainly thawing a more appropriate group of victim
   threads so they can release resources.
 
 - The 5 patch series "mm/damon: misc fixups and improvements for 6.18"
   from SeongJae Park is a bunch of small and unrelated fixups for DAMON.
 
 - The 7 patch series "mm/damon: define and use DAMON initialization
   check function" from SeongJae Park implement reliability and
   maintainability improvements to a recently-added bug fix.
 
 - The 2 patch series "mm/damon/stat: expose auto-tuned intervals and
   non-idle ages" from SeongJae Park provides additional transparency to
   userspace clients of the DAMON_STAT information.
 
 - The 2 patch series "Expand scope of khugepaged anonymous collapse"
   from Dev Jain removes some constraints on khubepaged's collapsing of
   anon VMAs.  It also increases the success rate of MADV_COLLAPSE against
   an anon vma.
 
 - The 2 patch series "mm: do not assume file == vma->vm_file in
   compat_vma_mmap_prepare()" from Lorenzo Stoakes moves us further towards
   removal of file_operations.mmap().  This patchset concentrates upon
   clearing up the treatment of stacked filesystems.
 
 - The 6 patch series "mm: Improve mlock tracking for large folios" from
   Kiryl Shutsemau provides some fixes and improvements to mlock's tracking
   of large folios.  /proc/meminfo's "Mlocked" field became more accurate.
 
 - The 2 patch series "mm/ksm: Fix incorrect accounting of KSM counters
   during fork" from Donet Tom fixes several user-visible KSM stats
   inaccuracies across forks and adds selftest code to verify these
   counters.
 
 - The 2 patch series "mm_slot: fix the usage of mm_slot_entry" from Wei
   Yang addresses some potential but presently benign issues in KSM's
   mm_slot handling.
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Merge tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - "mm, swap: improve cluster scan strategy" from Kairui Song improves
   performance and reduces the failure rate of swap cluster allocation

 - "support large align and nid in Rust allocators" from Vitaly Wool
   permits Rust allocators to set NUMA node and large alignment when
   perforning slub and vmalloc reallocs

 - "mm/damon/vaddr: support stat-purpose DAMOS" from Yueyang Pan extend
   DAMOS_STAT's handling of the DAMON operations sets for virtual
   address spaces for ops-level DAMOS filters

 - "execute PROCMAP_QUERY ioctl under per-vma lock" from Suren
   Baghdasaryan reduces mmap_lock contention during reads of
   /proc/pid/maps

 - "mm/mincore: minor clean up for swap cache checking" from Kairui Song
   performs some cleanup in the swap code

 - "mm: vm_normal_page*() improvements" from David Hildenbrand provides
   code cleanup in the pagemap code

 - "add persistent huge zero folio support" from Pankaj Raghav provides
   a block layer speedup by optionalls making the
   huge_zero_pagepersistent, instead of releasing it when its refcount
   falls to zero

 - "kho: fixes and cleanups" from Mike Rapoport adds a few touchups to
   the recently added Kexec Handover feature

 - "mm: make mm->flags a bitmap and 64-bit on all arches" from Lorenzo
   Stoakes turns mm_struct.flags into a bitmap. To end the constant
   struggle with space shortage on 32-bit conflicting with 64-bit's
   needs

 - "mm/swapfile.c and swap.h cleanup" from Chris Li cleans up some swap
   code

 - "selftests/mm: Fix false positives and skip unsupported tests" from
   Donet Tom fixes a few things in our selftests code

 - "prctl: extend PR_SET_THP_DISABLE to only provide THPs when advised"
   from David Hildenbrand "allows individual processes to opt-out of
   THP=always into THP=madvise, without affecting other workloads on the
   system".

   It's a long story - the [1/N] changelog spells out the considerations

 - "Add and use memdesc_flags_t" from Matthew Wilcox gets us started on
   the memdesc project. Please see

      https://kernelnewbies.org/MatthewWilcox/Memdescs and
      https://blogs.oracle.com/linux/post/introducing-memdesc

 - "Tiny optimization for large read operations" from Chi Zhiling
   improves the efficiency of the pagecache read path

 - "Better split_huge_page_test result check" from Zi Yan improves our
   folio splitting selftest code

 - "test that rmap behaves as expected" from Wei Yang adds some rmap
   selftests

 - "remove write_cache_pages()" from Christoph Hellwig removes that
   function and converts its two remaining callers

 - "selftests/mm: uffd-stress fixes" from Dev Jain fixes some UFFD
   selftests issues

 - "introduce kernel file mapped folios" from Boris Burkov introduces
   the concept of "kernel file pages". Using these permits btrfs to
   account its metadata pages to the root cgroup, rather than to the
   cgroups of random inappropriate tasks

 - "mm/pageblock: improve readability of some pageblock handling" from
   Wei Yang provides some readability improvements to the page allocator
   code

 - "mm/damon: support ARM32 with LPAE" from SeongJae Park teaches DAMON
   to understand arm32 highmem

 - "tools: testing: Use existing atomic.h for vma/maple tests" from
   Brendan Jackman performs some code cleanups and deduplication under
   tools/testing/

 - "maple_tree: Fix testing for 32bit compiles" from Liam Howlett fixes
   a couple of 32-bit issues in tools/testing/radix-tree.c

 - "kasan: unify kasan_enabled() and remove arch-specific
   implementations" from Sabyrzhan Tasbolatov moves KASAN arch-specific
   initialization code into a common arch-neutral implementation

 - "mm: remove zpool" from Johannes Weiner removes zspool - an
   indirection layer which now only redirects to a single thing
   (zsmalloc)

 - "mm: task_stack: Stack handling cleanups" from Pasha Tatashin makes a
   couple of cleanups in the fork code

 - "mm: remove nth_page()" from David Hildenbrand makes rather a lot of
   adjustments at various nth_page() callsites, eventually permitting
   the removal of that undesirable helper function

 - "introduce kasan.write_only option in hw-tags" from Yeoreum Yun
   creates a KASAN read-only mode for ARM, using that architecture's
   memory tagging feature. It is felt that a read-only mode KASAN is
   suitable for use in production systems rather than debug-only

 - "mm: hugetlb: cleanup hugetlb folio allocation" from Kefeng Wang does
   some tidying in the hugetlb folio allocation code

 - "mm: establish const-correctness for pointer parameters" from Max
   Kellermann makes quite a number of the MM API functions more accurate
   about the constness of their arguments. This was getting in the way
   of subsystems (in this case CEPH) when they attempt to improving
   their own const/non-const accuracy

 - "Cleanup free_pages() misuse" from Vishal Moola fixes a number of
   code sites which were confused over when to use free_pages() vs
   __free_pages()

 - "Add Rust abstraction for Maple Trees" from Alice Ryhl makes the
   mapletree code accessible to Rust. Required by nouveau and by its
   forthcoming successor: the new Rust Nova driver

 - "selftests/mm: split_huge_page_test: split_pte_mapped_thp
   improvements" from David Hildenbrand adds a fix and some cleanups to
   the thp selftesting code

 - "mm, swap: introduce swap table as swap cache (phase I)" from Chris
   Li and Kairui Song is the first step along the path to implementing
   "swap tables" - a new approach to swap allocation and state tracking
   which is expected to yield speed and space improvements. This
   patchset itself yields a 5-20% performance benefit in some situations

 - "Some ptdesc cleanups" from Matthew Wilcox utilizes the new memdesc
   layer to clean up the ptdesc code a little

 - "Fix va_high_addr_switch.sh test failure" from Chunyu Hu fixes some
   issues in our 5-level pagetable selftesting code

 - "Minor fixes for memory allocation profiling" from Suren Baghdasaryan
   addresses a couple of minor issues in relatively new memory
   allocation profiling feature

 - "Small cleanups" from Matthew Wilcox has a few cleanups in
   preparation for more memdesc work

 - "mm/damon: add addr_unit for DAMON_LRU_SORT and DAMON_RECLAIM" from
   Quanmin Yan makes some changes to DAMON in furtherance of supporting
   arm highmem

 - "selftests/mm: Add -Wunreachable-code and fix warnings" from Muhammad
   Anjum adds that compiler check to selftests code and fixes the
   fallout, by removing dead code

 - "Improvements to Victim Process Thawing and OOM Reaper Traversal
   Order" from zhongjinji makes a number of improvements in the OOM
   killer: mainly thawing a more appropriate group of victim threads so
   they can release resources

 - "mm/damon: misc fixups and improvements for 6.18" from SeongJae Park
   is a bunch of small and unrelated fixups for DAMON

 - "mm/damon: define and use DAMON initialization check function" from
   SeongJae Park implement reliability and maintainability improvements
   to a recently-added bug fix

 - "mm/damon/stat: expose auto-tuned intervals and non-idle ages" from
   SeongJae Park provides additional transparency to userspace clients
   of the DAMON_STAT information

 - "Expand scope of khugepaged anonymous collapse" from Dev Jain removes
   some constraints on khubepaged's collapsing of anon VMAs. It also
   increases the success rate of MADV_COLLAPSE against an anon vma

 - "mm: do not assume file == vma->vm_file in compat_vma_mmap_prepare()"
   from Lorenzo Stoakes moves us further towards removal of
   file_operations.mmap(). This patchset concentrates upon clearing up
   the treatment of stacked filesystems

 - "mm: Improve mlock tracking for large folios" from Kiryl Shutsemau
   provides some fixes and improvements to mlock's tracking of large
   folios. /proc/meminfo's "Mlocked" field became more accurate

 - "mm/ksm: Fix incorrect accounting of KSM counters during fork" from
   Donet Tom fixes several user-visible KSM stats inaccuracies across
   forks and adds selftest code to verify these counters

 - "mm_slot: fix the usage of mm_slot_entry" from Wei Yang addresses
   some potential but presently benign issues in KSM's mm_slot handling

* tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (372 commits)
  mm: swap: check for stable address space before operating on the VMA
  mm: convert folio_page() back to a macro
  mm/khugepaged: use start_addr/addr for improved readability
  hugetlbfs: skip VMAs without shareable locks in hugetlb_vmdelete_list
  alloc_tag: fix boot failure due to NULL pointer dereference
  mm: silence data-race in update_hiwater_rss
  mm/memory-failure: don't select MEMORY_ISOLATION
  mm/khugepaged: remove definition of struct khugepaged_mm_slot
  mm/ksm: get mm_slot by mm_slot_entry() when slot is !NULL
  hugetlb: increase number of reserving hugepages via cmdline
  selftests/mm: add fork inheritance test for ksm_merging_pages counter
  mm/ksm: fix incorrect KSM counter handling in mm_struct during fork
  drivers/base/node: fix double free in register_one_node()
  mm: remove PMD alignment constraint in execmem_vmalloc()
  mm/memory_hotplug: fix typo 'esecially' -> 'especially'
  mm/rmap: improve mlock tracking for large folios
  mm/filemap: map entire large folio faultaround
  mm/fault: try to map the entire file folio in finish_fault()
  mm/rmap: mlock large folios in try_to_unmap_one()
  mm/rmap: fix a mlock race condition in folio_referenced_one()
  ...
 2025-10-02 18:18:33 -07:00
Linus Torvalds
18b19abc37 namespace-6.18-rc1 
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Merge tag 'namespace-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull namespace updates from Christian Brauner:
 "This contains a larger set of changes around the generic namespace
  infrastructure of the kernel.

  Each specific namespace type (net, cgroup, mnt, ...) embedds a struct
  ns_common which carries the reference count of the namespace and so
  on.

  We open-coded and cargo-culted so many quirks for each namespace type
  that it just wasn't scalable anymore. So given there's a bunch of new
  changes coming in that area I've started cleaning all of this up.

  The core change is to make it possible to correctly initialize every
  namespace uniformly and derive the correct initialization settings
  from the type of the namespace such as namespace operations, namespace
  type and so on. This leaves the new ns_common_init() function with a
  single parameter which is the specific namespace type which derives
  the correct parameters statically. This also means the compiler will
  yell as soon as someone does something remotely fishy.

  The ns_common_init() addition also allows us to remove ns_alloc_inum()
  and drops any special-casing of the initial network namespace in the
  network namespace initialization code that Linus complained about.

  Another part is reworking the reference counting. The reference
  counting was open-coded and copy-pasted for each namespace type even
  though they all followed the same rules. This also removes all open
  accesses to the reference count and makes it private and only uses a
  very small set of dedicated helpers to manipulate them just like we do
  for e.g., files.

  In addition this generalizes the mount namespace iteration
  infrastructure introduced a few cycles ago. As reminder, the vfs makes
  it possible to iterate sequentially and bidirectionally through all
  mount namespaces on the system or all mount namespaces that the caller
  holds privilege over. This allow userspace to iterate over all mounts
  in all mount namespaces using the listmount() and statmount() system
  call.

  Each mount namespace has a unique identifier for the lifetime of the
  systems that is exposed to userspace. The network namespace also has a
  unique identifier working exactly the same way. This extends the
  concept to all other namespace types.

  The new nstree type makes it possible to lookup namespaces purely by
  their identifier and to walk the namespace list sequentially and
  bidirectionally for all namespace types, allowing userspace to iterate
  through all namespaces. Looking up namespaces in the namespace tree
  works completely locklessly.

  This also means we can move the mount namespace onto the generic
  infrastructure and remove a bunch of code and members from struct
  mnt_namespace itself.

  There's a bunch of stuff coming on top of this in the future but for
  now this uses the generic namespace tree to extend a concept
  introduced first for pidfs a few cycles ago. For a while now we have
  supported pidfs file handles for pidfds. This has proven to be very
  useful.

  This extends the concept to cover namespaces as well. It is possible
  to encode and decode namespace file handles using the common
  name_to_handle_at() and open_by_handle_at() apis.

  As with pidfs file handles, namespace file handles are exhaustive,
  meaning it is not required to actually hold a reference to nsfs in
  able to decode aka open_by_handle_at() a namespace file handle.
  Instead the FD_NSFS_ROOT constant can be passed which will let the
  kernel grab a reference to the root of nsfs internally and thus decode
  the file handle.

  Namespaces file descriptors can already be derived from pidfds which
  means they aren't subject to overmount protection bugs. IOW, it's
  irrelevant if the caller would not have access to an appropriate
  /proc/<pid>/ns/ directory as they could always just derive the
  namespace based on a pidfd already.

  It has the same advantage as pidfds. It's possible to reliably and for
  the lifetime of the system refer to a namespace without pinning any
  resources and to compare them trivially.

  Permission checking is kept simple. If the caller is located in the
  namespace the file handle refers to they are able to open it otherwise
  they must hold privilege over the owning namespace of the relevant
  namespace.

  The namespace file handle layout is exposed as uapi and has a stable
  and extensible format. For now it simply contains the namespace
  identifier, the namespace type, and the inode number. The stable
  format means that userspace may construct its own namespace file
  handles without going through name_to_handle_at() as they are already
  allowed for pidfs and cgroup file handles"

* tag 'namespace-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (65 commits)
  ns: drop assert
  ns: move ns type into struct ns_common
  nstree: make struct ns_tree private
  ns: add ns_debug()
  ns: simplify ns_common_init() further
  cgroup: add missing ns_common include
  ns: use inode initializer for initial namespaces
  selftests/namespaces: verify initial namespace inode numbers
  ns: rename to __ns_ref
  nsfs: port to ns_ref_*() helpers
  net: port to ns_ref_*() helpers
  uts: port to ns_ref_*() helpers
  ipv4: use check_net()
  net: use check_net()
  net-sysfs: use check_net()
  user: port to ns_ref_*() helpers
  time: port to ns_ref_*() helpers
  pid: port to ns_ref_*() helpers
  ipc: port to ns_ref_*() helpers
  cgroup: port to ns_ref_*() helpers
  ...
 2025-09-29 11:20:29 -07:00
Linus Torvalds
e571372101 vfs-6.18-rc1.pidfs 
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Merge tag 'vfs-6.18-rc1.pidfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull pidfs updates from Christian Brauner:
 "This just contains a few changes to pid_nr_ns() to make it more robust
  and cleans up or improves a few users that ab- or misuse it currently"

* tag 'vfs-6.18-rc1.pidfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  pid: change task_state() to use task_ppid_nr_ns()
  pid: change bacct_add_tsk() to use task_ppid_nr_ns()
  pid: make __task_pid_nr_ns(ns => NULL) safe for zombie callers
  pid: Add a judgment for ns null in pid_nr_ns
 2025-09-29 10:02:35 -07:00
Linus Torvalds
b7ce6fa90f vfs-6.18-rc1.misc 
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Merge tag 'vfs-6.18-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull misc vfs updates from Christian Brauner:
 "This contains the usual selections of misc updates for this cycle.

  Features:

   - Add "initramfs_options" parameter to set initramfs mount options.
     This allows to add specific mount options to the rootfs to e.g.,
     limit the memory size

   - Add RWF_NOSIGNAL flag for pwritev2()

     Add RWF_NOSIGNAL flag for pwritev2. This flag prevents the SIGPIPE
     signal from being raised when writing on disconnected pipes or
     sockets. The flag is handled directly by the pipe filesystem and
     converted to the existing MSG_NOSIGNAL flag for sockets

   - Allow to pass pid namespace as procfs mount option

     Ever since the introduction of pid namespaces, procfs has had very
     implicit behaviour surrounding them (the pidns used by a procfs
     mount is auto-selected based on the mounting process's active
     pidns, and the pidns itself is basically hidden once the mount has
     been constructed)

     This implicit behaviour has historically meant that userspace was
     required to do some special dances in order to configure the pidns
     of a procfs mount as desired. Examples include:

     * In order to bypass the mnt_too_revealing() check, Kubernetes
       creates a procfs mount from an empty pidns so that user
       namespaced containers can be nested (without this, the nested
       containers would fail to mount procfs)

       But this requires forking off a helper process because you cannot
       just one-shot this using mount(2)

     * Container runtimes in general need to fork into a container
       before configuring its mounts, which can lead to security issues
       in the case of shared-pidns containers (a privileged process in
       the pidns can interact with your container runtime process)

       While SUID_DUMP_DISABLE and user namespaces make this less of an
       issue, the strict need for this due to a minor uAPI wart is kind
       of unfortunate

       Things would be much easier if there was a way for userspace to
       just specify the pidns they want. So this pull request contains
       changes to implement a new "pidns" argument which can be set
       using fsconfig(2):

           fsconfig(procfd, FSCONFIG_SET_FD, "pidns", NULL, nsfd);
           fsconfig(procfd, FSCONFIG_SET_STRING, "pidns", "/proc/self/ns/pid", 0);

       or classic mount(2) / mount(8):

           // mount -t proc -o pidns=/proc/self/ns/pid proc /tmp/proc
           mount("proc", "/tmp/proc", "proc", MS_..., "pidns=/proc/self/ns/pid");

  Cleanups:

   - Remove the last references to EXPORT_OP_ASYNC_LOCK

   - Make file_remove_privs_flags() static

   - Remove redundant __GFP_NOWARN when GFP_NOWAIT is used

   - Use try_cmpxchg() in start_dir_add()

   - Use try_cmpxchg() in sb_init_done_wq()

   - Replace offsetof() with struct_size() in ioctl_file_dedupe_range()

   - Remove vfs_ioctl() export

   - Replace rwlock() with spinlock in epoll code as rwlock causes
     priority inversion on preempt rt kernels

   - Make ns_entries in fs/proc/namespaces const

   - Use a switch() statement() in init_special_inode() just like we do
     in may_open()

   - Use struct_size() in dir_add() in the initramfs code

   - Use str_plural() in rd_load_image()

   - Replace strcpy() with strscpy() in find_link()

   - Rename generic_delete_inode() to inode_just_drop() and
     generic_drop_inode() to inode_generic_drop()

   - Remove unused arguments from fcntl_{g,s}et_rw_hint()

  Fixes:

   - Document @name parameter for name_contains_dotdot() helper

   - Fix spelling mistake

   - Always return zero from replace_fd() instead of the file descriptor
     number

   - Limit the size for copy_file_range() in compat mode to prevent a
     signed overflow

   - Fix debugfs mount options not being applied

   - Verify the inode mode when loading it from disk in minixfs

   - Verify the inode mode when loading it from disk in cramfs

   - Don't trigger automounts with RESOLVE_NO_XDEV

     If openat2() was called with RESOLVE_NO_XDEV it didn't traverse
     through automounts, but could still trigger them

   - Add FL_RECLAIM flag to show_fl_flags() macro so it appears in
     tracepoints

   - Fix unused variable warning in rd_load_image() on s390

   - Make INITRAMFS_PRESERVE_MTIME depend on BLK_DEV_INITRD

   - Use ns_capable_noaudit() when determining net sysctl permissions

   - Don't call path_put() under namespace semaphore in listmount() and
     statmount()"

* tag 'vfs-6.18-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (38 commits)
  fcntl: trim arguments
  listmount: don't call path_put() under namespace semaphore
  statmount: don't call path_put() under namespace semaphore
  pid: use ns_capable_noaudit() when determining net sysctl permissions
  fs: rename generic_delete_inode() and generic_drop_inode()
  init: INITRAMFS_PRESERVE_MTIME should depend on BLK_DEV_INITRD
  initramfs: Replace strcpy() with strscpy() in find_link()
  initrd: Use str_plural() in rd_load_image()
  initramfs: Use struct_size() helper to improve dir_add()
  initrd: Fix unused variable warning in rd_load_image() on s390
  fs: use the switch statement in init_special_inode()
  fs/proc/namespaces: make ns_entries const
  filelock: add FL_RECLAIM to show_fl_flags() macro
  eventpoll: Replace rwlock with spinlock
  selftests/proc: add tests for new pidns APIs
  procfs: add "pidns" mount option
  pidns: move is-ancestor logic to helper
  openat2: don't trigger automounts with RESOLVE_NO_XDEV
  namei: move cross-device check to __traverse_mounts
  namei: remove LOOKUP_NO_XDEV check from handle_mounts
  ...
 2025-09-29 09:03:07 -07:00
Jakub Acs
28aa29986d fs/proc/task_mmu: check p->vec_buf for NULL 
When the PAGEMAP_SCAN ioctl is invoked with vec_len = 0 reaches
pagemap_scan_backout_range(), kernel panics with null-ptr-deref:

[   44.936808] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI
[   44.937797] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
[   44.938391] CPU: 1 UID: 0 PID: 2480 Comm: reproducer Not tainted 6.17.0-rc6 #22 PREEMPT(none)
[   44.939062] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[   44.939935] RIP: 0010:pagemap_scan_thp_entry.isra.0+0x741/0xa80

<snip registers, unreliable trace>

[   44.946828] Call Trace:
[   44.947030]  <TASK>
[   44.949219]  pagemap_scan_pmd_entry+0xec/0xfa0
[   44.952593]  walk_pmd_range.isra.0+0x302/0x910
[   44.954069]  walk_pud_range.isra.0+0x419/0x790
[   44.954427]  walk_p4d_range+0x41e/0x620
[   44.954743]  walk_pgd_range+0x31e/0x630
[   44.955057]  __walk_page_range+0x160/0x670
[   44.956883]  walk_page_range_mm+0x408/0x980
[   44.958677]  walk_page_range+0x66/0x90
[   44.958984]  do_pagemap_scan+0x28d/0x9c0
[   44.961833]  do_pagemap_cmd+0x59/0x80
[   44.962484]  __x64_sys_ioctl+0x18d/0x210
[   44.962804]  do_syscall_64+0x5b/0x290
[   44.963111]  entry_SYSCALL_64_after_hwframe+0x76/0x7e

vec_len = 0 in pagemap_scan_init_bounce_buffer() means no buffers are
allocated and p->vec_buf remains set to NULL.

This breaks an assumption made later in pagemap_scan_backout_range(), that
page_region is always allocated for p->vec_buf_index.

Fix it by explicitly checking p->vec_buf for NULL before dereferencing.

Other sites that might run into same deref-issue are already (directly or
transitively) protected by checking p->vec_buf.

Note:
From PAGEMAP_SCAN man page, it seems vec_len = 0 is valid when no output
is requested and it's only the side effects caller is interested in,
hence it passes check in pagemap_scan_get_args().

This issue was found by syzkaller.

Link: https://lkml.kernel.org/r/20250922082206.6889-1-acsjakub@amazon.de
Fixes: 52526ca7fd ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs")
Signed-off-by: Jakub Acs <acsjakub@amazon.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Jinjiang Tu <tujinjiang@huawei.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Penglei Jiang <superman.xpt@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-25 16:10:34 -07:00
Miaohe Lin
5ce1dbfdd8 mm/hwpoison: decouple hwpoison_filter from mm/memory-failure.c 
mm/memory-failure.c defines and uses hwpoison_filter_* parameters but the
values of those parameters can only be modified via mm/hwpoison-inject.c
from userspace.  They have a potentially different life time.  Decouple
those parameters from mm/memory-failure.c to fix this broken layering.

Link: https://lkml.kernel.org/r/20250904062258.3336092-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-21 14:22:21 -07:00
Andrew Morton
bc9950b56f Merge branch 'mm-hotfixes-stable' into mm-stable in order to pick up 
changes required by mm-stable material: hugetlb and damon.
 2025-09-21 14:19:36 -07:00
Mateusz Guzik
f99b391778
fs: rename generic_delete_inode() and generic_drop_inode() 
generic_delete_inode() is rather misleading for what the routine is
doing. inode_just_drop() should be much clearer.

The new naming is inconsistent with generic_drop_inode(), so rename that
one as well with inode_ as the suffix.

No functional changes.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2025-09-15 16:09:42 +02:00
Max Kellermann
796667c9dc
fs/proc/namespaces: make ns_entries const 
Global variables that are never modified should be "const" so so that
they live in the .rodata section instead of the .data section of the
kernel, gaining the protection of the kernel's strict memory
permissions as described in Documentation/security/self-protection.rst

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2025-09-15 14:28:37 +02:00
zhang jiao
13f23538ef fs/proc/base.c: fix the wrong format specifier 
Use '%d' instead of '%u' for int.

Link: https://lkml.kernel.org/r/20250903083948.2536-1-zhangjiao2@cmss.chinamobile.com
Signed-off-by: zhang jiao <zhangjiao2@cmss.chinamobile.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-13 17:32:54 -07:00
Matthew Wilcox (Oracle)
53fbef56e0 mm: introduce memdesc_flags_t 
Patch series "Add and use memdesc_flags_t".

At some point struct page will be separated from struct slab and struct
folio.  This is a step towards that by introducing a type for the 'flags'
word of all three structures.  This gives us a certain amount of type
safety by establishing that some of these unsigned longs are different
from other unsigned longs in that they contain things like node ID,
section number and zone number in the upper bits.  That lets us have
functions that can be easily called by anyone who has a slab, folio or
page (but not easily by anyone else) to get the node or zone.

There's going to be some unusual merge problems with this as some odd bits
of the kernel decide they want to print out the flags value or something
similar by writing page->flags and now they'll need to write page->flags.f
instead.  That's most of the churn here.  Maybe we should be removing
these things from the debug output?


This patch (of 11):

Wrap the unsigned long flags in a typedef.  In upcoming patches, this will
provide a strong hint that you can't just pass a random unsigned long to
functions which take this as an argument.

[willy@infradead.org: s/flags/flags.f/ in several architectures]
  Link: https://lkml.kernel.org/r/aKMgPRLD-WnkPxYm@casper.infradead.org
[nicola.vetrini@gmail.com: mips: fix compilation error]
  Link: https://lore.kernel.org/lkml/CA+G9fYvkpmqGr6wjBNHY=dRp71PLCoi2341JxOudi60yqaeUdg@mail.gmail.com/
  Link: https://lkml.kernel.org/r/20250825214245.1838158-1-nicola.vetrini@gmail.com
Link: https://lkml.kernel.org/r/20250805172307.1302730-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20250805172307.1302730-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Zi Yan <ziy@nvidia.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-13 16:55:07 -07:00
David Hildenbrand
1f1c061089 mm/huge_memory: convert "tva_flags" to "enum tva_type" 
When determining which THP orders are eligible for a VMA mapping, we have
previously specified tva_flags, however it turns out it is really not
necessary to treat these as flags.

Rather, we distinguish between distinct modes.

The only case where we previously combined flags was with
TVA_ENFORCE_SYSFS, but we can avoid this by observing that this is the
default, except for MADV_COLLAPSE or an edge cases in
collapse_pte_mapped_thp() and hugepage_vma_revalidate(), and adding a mode
specifically for this case - TVA_FORCED_COLLAPSE.

We have:
* smaps handling for showing "THPeligible"
* Pagefault handling
* khugepaged handling
* Forced collapse handling: primarily MADV_COLLAPSE, but also for
  an edge case in collapse_pte_mapped_thp()

Disregarding the edge cases, we only want to ignore sysfs settings only
when we are forcing a collapse through MADV_COLLAPSE, otherwise we want to
enforce it, hence this patch does the following flag to enum conversions:

* TVA_SMAPS | TVA_ENFORCE_SYSFS -> TVA_SMAPS
* TVA_IN_PF | TVA_ENFORCE_SYSFS -> TVA_PAGEFAULT
* TVA_ENFORCE_SYSFS             -> TVA_KHUGEPAGED
* 0                             -> TVA_FORCED_COLLAPSE

With this change, we immediately know if we are in the forced collapse
case, which will be valuable next.

Link: https://lkml.kernel.org/r/20250815135549.130506-3-usamaarif642@gmail.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Acked-by: Usama Arif <usamaarif642@gmail.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yafang <laoar.shao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-13 16:55:05 -07:00
David Hildenbrand
9dc21bbd62 prctl: extend PR_SET_THP_DISABLE to optionally exclude VM_HUGEPAGE 
Patch series "prctl: extend PR_SET_THP_DISABLE to only provide THPs when
advised", v5.

This will allow individual processes to opt-out of THP = "always" into THP
= "madvise", without affecting other workloads on the system.  This has
been extensively discussed on the mailing list and has been summarized
very well by David in the first patch which also includes the links to
alternatives, please refer to the first patch commit message for the
motivation for this series.

Patch 1 adds the PR_THP_DISABLE_EXCEPT_ADVISED flag to implement this,
along with the MMF changes.

Patch 2 is a cleanup patch for tva_flags that will allow the forced
collapse case to be transmitted to vma_thp_disabled (which is done in
patch 3).

Patch 4 adds documentation for PR_SET_THP_DISABLE/PR_GET_THP_DISABLE.

Patches 6-7 implement the selftests for PR_SET_THP_DISABLE for completely
disabling THPs (old behaviour) and only enabling it at advise
(PR_THP_DISABLE_EXCEPT_ADVISED).


This patch (of 7):

People want to make use of more THPs, for example, moving from the "never"
system policy to "madvise", or from "madvise" to "always".

While this is great news for every THP desperately waiting to get
allocated out there, apparently there are some workloads that require a
bit of care during that transition: individual processes may need to
opt-out from this behavior for various reasons, and this should be
permitted without needing to make all other workloads on the system
similarly opt-out.

The following scenarios are imaginable:

(1) Switch from "none" system policy to "madvise"/"always", but keep THPs
    disabled for selected workloads.

(2) Stay at "none" system policy, but enable THPs for selected
    workloads, making only these workloads use the "madvise" or "always"
    policy.

(3) Switch from "madvise" system policy to "always", but keep the
    "madvise" policy for selected workloads: allocate THPs only when
    advised.

(4) Stay at "madvise" system policy, but enable THPs even when not advised
    for selected workloads -- "always" policy.

Once can emulate (2) through (1), by setting the system policy to
"madvise"/"always" while disabling THPs for all processes that don't want
THPs.  It requires configuring all workloads, but that is a user-space
problem to sort out.

(4) can be emulated through (3) in a similar way.

Back when (1) was relevant in the past, as people started enabling THPs,
we added PR_SET_THP_DISABLE, so relevant workloads that were not ready yet
(i.e., used by Redis) were able to just disable THPs completely.  Redis
still implements the option to use this interface to disable THPs
completely.

With PR_SET_THP_DISABLE, we added a way to force-disable THPs for a
workload -- a process, including fork+exec'ed process hierarchy.  That
essentially made us support (1): simply disable THPs for all workloads
that are not ready for THPs yet, while still enabling THPs system-wide.

The quest for handling (3) and (4) started, but current approaches
(completely new prctl, options to set other policies per process,
alternatives to prctl -- mctrl, cgroup handling) don't look particularly
promising.  Likely, the future will use bpf or something similar to
implement better policies, in particular to also make better decisions
about THP sizes to use, but this will certainly take a while as that work
just started.

Long story short: a simple enable/disable is not really suitable for the
future, so we're not willing to add completely new toggles.

While we could emulate (3)+(4) through (1)+(2) by simply disabling THPs
completely for these processes, this is a step backwards, because these
processes can no longer allocate THPs in regions where THPs were
explicitly advised: regions flagged as VM_HUGEPAGE.  Apparently, that
imposes a problem for relevant workloads, because "not THPs" is certainly
worse than "THPs only when advised".

Could we simply relax PR_SET_THP_DISABLE, to "disable THPs unless not
explicitly advised by the app through MAD_HUGEPAGE"?  *maybe*, but this
would change the documented semantics quite a bit, and the versatility to
use it for debugging purposes, so I am not 100% sure that is what we want
-- although it would certainly be much easier.

So instead, as an easy way forward for (3) and (4), add an option to
make PR_SET_THP_DISABLE disable *less* THPs for a process.

In essence, this patch:

(A) Adds PR_THP_DISABLE_EXCEPT_ADVISED, to be used as a flag in arg3
    of prctl(PR_SET_THP_DISABLE) when disabling THPs (arg2 != 0).

    prctl(PR_SET_THP_DISABLE, 1, PR_THP_DISABLE_EXCEPT_ADVISED).

(B) Makes prctl(PR_GET_THP_DISABLE) return 3 if
    PR_THP_DISABLE_EXCEPT_ADVISED was set while disabling.

    Previously, it would return 1 if THPs were disabled completely. Now
    it returns the set flags as well: 3 if PR_THP_DISABLE_EXCEPT_ADVISED
    was set.

(C) Renames MMF_DISABLE_THP to MMF_DISABLE_THP_COMPLETELY, to express
    the semantics clearly.

    Fortunately, there are only two instances outside of prctl() code.

(D) Adds MMF_DISABLE_THP_EXCEPT_ADVISED to express "no THP except for VMAs
    with VM_HUGEPAGE" -- essentially "thp=madvise" behavior

    Fortunately, we only have to extend vma_thp_disabled().

(E) Indicates "THP_enabled: 0" in /proc/pid/status only if THPs are
    disabled completely

    Only indicating that THPs are disabled when they are really disabled
    completely, not only partially.

    For now, we don't add another interface to obtained whether THPs
    are disabled partially (PR_THP_DISABLE_EXCEPT_ADVISED was set). If
    ever required, we could add a new entry.

The documented semantics in the man page for PR_SET_THP_DISABLE "is
inherited by a child created via fork(2) and is preserved across
execve(2)" is maintained.  This behavior, for example, allows for
disabling THPs for a workload through the launching process (e.g., systemd
where we fork() a helper process to then exec()).

For now, MADV_COLLAPSE will *fail* in regions without VM_HUGEPAGE and
VM_NOHUGEPAGE.  As MADV_COLLAPSE is a clear advise that user space thinks
a THP is a good idea, we'll enable that separately next (requiring a bit
of cleanup first).

There is currently not way to prevent that a process will not issue
PR_SET_THP_DISABLE itself to re-enable THP.  There are not really known
users for re-enabling it, and it's against the purpose of the original
interface.  So if ever required, we could investigate just forbidding to
re-enable them, or make this somehow configurable.

Link: https://lkml.kernel.org/r/20250815135549.130506-1-usamaarif642@gmail.com
Link: https://lkml.kernel.org/r/20250815135549.130506-2-usamaarif642@gmail.com
Acked-by: Zi Yan <ziy@nvidia.com>
Acked-by: Usama Arif <usamaarif642@gmail.com>
Tested-by: Usama Arif <usamaarif642@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yafang <laoar.shao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-13 16:55:05 -07:00
Lorenzo Stoakes
d14d3f535e mm: convert remaining users to mm_flags_*() accessors 
As part of the effort to move to mm->flags becoming a bitmap field,
convert existing users to making use of the mm_flags_*() accessors which
will, when the conversion is complete, be the only means of accessing
mm_struct flags.

No functional change intended.

Link: https://lkml.kernel.org/r/cc67a56f9a8746a8ec7d9791853dc892c1c33e0b.1755012943.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Namhyung kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-13 16:54:58 -07:00
Lorenzo Stoakes
39f8049cd4 mm: update coredump logic to correctly use bitmap mm flags 
The coredump logic is slightly different from other users in that it both
stores mm flags and additionally sets and gets using masks.

Since the MMF_DUMPABLE_* flags must remain as they are for uABI reasons,
and of course these are within the first 32-bits of the flags, it is
reasonable to provide access to these in the same fashion so this logic
can all still keep working as it has been.

Therefore, introduce coredump-specific helpers __mm_flags_get_dumpable()
and __mm_flags_set_mask_dumpable() for this purpose, and update all core
dump users of mm flags to use these.

[lorenzo.stoakes@oracle.com: abstract set_mask_bits() invocation to mm_types.h to satisfy ARC]
  Link: https://lkml.kernel.org/r/0e7ad263-1ff7-446d-81fe-97cff9c0e7ed@lucifer.local
Link: https://lkml.kernel.org/r/2a5075f7e3c5b367d988178c79a3063d12ee53a9.1755012943.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Namhyung kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-13 16:54:57 -07:00
Suren Baghdasaryan
d9d1c2d817 fs/proc/task_mmu: execute PROCMAP_QUERY ioctl under per-vma locks 
Utilize per-vma locks to stabilize vma after lookup without taking
mmap_lock during PROCMAP_QUERY ioctl execution. If vma lock is
contended, we fall back to mmap_lock but take it only momentarily
to lock the vma and release the mmap_lock. In a very unlikely case
of vm_refcnt overflow, this fall back path will fail and ioctl is
done under mmap_lock protection.

This change is designed to reduce mmap_lock contention and prevent
PROCMAP_QUERY ioctl calls from blocking address space updates.

Link: https://lkml.kernel.org/r/20250808152850.2580887-4-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Weißschuh <linux@weissschuh.net>
Cc: T.J. Mercier <tjmercier@google.com>
Cc: Ye Bin <yebin10@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-13 16:54:48 -07:00
Suren Baghdasaryan
ee737a5a10 fs/proc/task_mmu: factor out proc_maps_private fields used by PROCMAP_QUERY 
Refactor struct proc_maps_private so that the fields used by PROCMAP_QUERY
ioctl are moved into a separate structure. In the next patch this allows
ioctl to reuse some of the functions used for reading /proc/pid/maps
without using file->private_data. This prevents concurrent modification
of file->private_data members by ioctl and /proc/pid/maps readers.

The change is pure code refactoring and has no functional changes.

Link: https://lkml.kernel.org/r/20250808152850.2580887-3-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Weißschuh <linux@weissschuh.net>
Cc: T.J. Mercier <tjmercier@google.com>
Cc: Ye Bin <yebin10@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-13 16:54:48 -07:00
wangzijie
0ce9398aa0 proc: fix type confusion in pde_set_flags() 
Commit 2ce3d282bd ("proc: fix missing pde_set_flags() for net proc
files") missed a key part in the definition of proc_dir_entry:

union {
	const struct proc_ops *proc_ops;
	const struct file_operations *proc_dir_ops;
};

So dereference of ->proc_ops assumes it is a proc_ops structure results in
type confusion and make NULL check for 'proc_ops' not work for proc dir.

Add !S_ISDIR(dp->mode) test before calling pde_set_flags() to fix it.

Link: https://lkml.kernel.org/r/20250904135715.3972782-1-wangzijie1@honor.com
Fixes: 2ce3d282bd ("proc: fix missing pde_set_flags() for net proc files")
Signed-off-by: wangzijie <wangzijie1@honor.com>
Reported-by: Brad Spengler <spender@grsecurity.net>
Closes: https://lore.kernel.org/all/20250903065758.3678537-1-wangzijie1@honor.com/
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Stefano Brivio <sbrivio@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-09-08 23:45:12 -07:00
Aleksa Sarai
fe49652e36
procfs: add "pidns" mount option 
Since the introduction of pid namespaces, their interaction with procfs
has been entirely implicit in ways that require a lot of dancing around
by programs that need to construct sandboxes with different PID
namespaces.

Being able to explicitly specify the pid namespace to use when
constructing a procfs super block will allow programs to no longer need
to fork off a process which does then does unshare(2) / setns(2) and
forks again in order to construct a procfs in a pidns.

So, provide a "pidns" mount option which allows such users to just
explicitly state which pid namespace they want that procfs instance to
use. This interface can be used with fsconfig(2) either with a file
descriptor or a path:

  fsconfig(procfd, FSCONFIG_SET_FD, "pidns", NULL, nsfd);
  fsconfig(procfd, FSCONFIG_SET_STRING, "pidns", "/proc/self/ns/pid", 0);

or with classic mount(2) / mount(8):

  // mount -t proc -o pidns=/proc/self/ns/pid proc /tmp/proc
  mount("proc", "/tmp/proc", "proc", MS_..., "pidns=/proc/self/ns/pid");

As this new API is effectively shorthand for setns(2) followed by
mount(2), the permission model for this mirrors pidns_install() to avoid
opening up new attack surfaces by loosening the existing permission
model.

In order to avoid having to RCU-protect all users of proc_pid_ns() (to
avoid UAFs), attempting to reconfigure an existing procfs instance's pid
namespace will error out with -EBUSY. Creating new procfs instances is
quite cheap, so this should not be an impediment to most users, and lets
us avoid a lot of churn in fs/proc/* for a feature that it seems
unlikely userspace would use.

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Link: https://lore.kernel.org/20250805-procfs-pidns-api-v4-2-705f984940e7@cyphar.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2025-09-02 11:37:24 +02:00
wangzijie
2ce3d282bd proc: fix missing pde_set_flags() for net proc files 
To avoid potential UAF issues during module removal races, we use
pde_set_flags() to save proc_ops flags in PDE itself before
proc_register(), and then use pde_has_proc_*() helpers instead of directly
dereferencing pde->proc_ops->*.

However, the pde_set_flags() call was missing when creating net related
proc files.  This omission caused incorrect behavior which FMODE_LSEEK was
being cleared inappropriately in proc_reg_open() for net proc files.  Lars
reported it in this link[1].

Fix this by ensuring pde_set_flags() is called when register proc entry,
and add NULL check for proc_ops in pde_set_flags().

[wangzijie1@honor.com: stash pde->proc_ops in a local const variable, per Christian]
  Link: https://lkml.kernel.org/r/20250821105806.1453833-1-wangzijie1@honor.com
Link: https://lkml.kernel.org/r/20250818123102.959595-1-wangzijie1@honor.com
Link: https://lore.kernel.org/all/20250815195616.64497967@chagall.paradoxon.rec/ [1]
Fixes: ff7ec8dc1b ("proc: use the same treatment to check proc_lseek as ones for proc_read_iter et.al")
Signed-off-by: wangzijie <wangzijie1@honor.com>
Reported-by: Lars Wendler <polynomial-c@gmx.de>
Tested-by: Stefano Brivio <sbrivio@redhat.com>
Tested-by: Petr Vaněk <pv@excello.cz>
Tested by: Lars Wendler <polynomial-c@gmx.de>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Kirill A. Shutemov <k.shutemov@gmail.com>
Cc: wangzijie <wangzijie1@honor.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-08-27 22:45:44 -07:00
Oleg Nesterov
d00f523285
pid: change task_state() to use task_ppid_nr_ns() 
to simplify the code.

Note that only tpid and max_fds really need rcu_read_lock(), we could move
task_ppid_nr_ns/task_tgid_nr_ns/task_numa_group_id/get_task_cred outside of
rcu read section.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/20250810173620.GA20007@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2025-08-19 13:38:21 +02:00
Jialin Wang
c0e1b774f6 proc: proc_maps_open allow proc_mem_open to return NULL 
The commit 65c6604725 ("proc: fix the issue of proc_mem_open returning
NULL") caused proc_maps_open() to return -ESRCH when proc_mem_open()
returns NULL.  This breaks legitimate /proc/<pid>/maps access for kernel
threads since kernel threads have NULL mm_struct.

The regression causes perf to fail and exit when profiling a kernel
thread:

  # perf record -v -g -p $(pgrep kswapd0)
  ...
  couldn't open /proc/65/task/65/maps

This patch partially reverts the commit to fix it.

Link: https://lkml.kernel.org/r/20250807165455.73656-1-wjl.linux@gmail.com
Fixes: 65c6604725 ("proc: fix the issue of proc_mem_open returning NULL")
Signed-off-by: Jialin Wang <wjl.linux@gmail.com>
Cc: Penglei Jiang <superman.xpt@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-08-11 23:01:00 -07:00
Jinjiang Tu
aa5a10b070 fs/proc/task_mmu: hold PTL in pagemap_hugetlb_range and gather_hugetlb_stats 
Hold PTL in pagemap_hugetlb_range() and gather_hugetlb_stats() to avoid
operating on stale page, as pagemap_pmd_range() and gather_pte_stats()
have done.

Link: https://lkml.kernel.org/r/20250724090958.455887-3-tujinjiang@huawei.com
Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Brahmajit Das <brahmajit.xyz@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Rientjes <rientjes@google.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joern Engel <joern@logfs.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-08-05 13:38:39 -07:00
Jinjiang Tu
45d19b4b6c mm/smaps: fix race between smaps_hugetlb_range and migration 
smaps_hugetlb_range() handles the pte without holdling ptl, and may be
concurrenct with migration, leaing to BUG_ON in pfn_swap_entry_to_page(). 
The race is as follows.

smaps_hugetlb_range              migrate_pages
  huge_ptep_get
                                   remove_migration_ptes
				   folio_unlock
  pfn_swap_entry_folio
    BUG_ON

To fix it, hold ptl lock in smaps_hugetlb_range().

Link: https://lkml.kernel.org/r/20250724090958.455887-1-tujinjiang@huawei.com
Link: https://lkml.kernel.org/r/20250724090958.455887-2-tujinjiang@huawei.com
Fixes: 25ee01a2fc ("mm: hugetlb: proc: add hugetlb-related fields to /proc/PID/smaps")
Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Brahmajit Das <brahmajit.xyz@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Rientjes <rientjes@google.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joern Engel <joern@logfs.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-08-05 13:38:39 -07:00
Linus Torvalds
e991acf1bc Significant patch series in this pull request: 
- The 2 patch series "squashfs: Remove page->mapping references" from
   Matthew Wilcox gets us closer to being able to remove page->mapping.
 
 - The 5 patch series "relayfs: misc changes" from Jason Xing does some
   maintenance and minor feature addition work in relayfs.
 
 - The 5 patch series "kdump: crashkernel reservation from CMA" from Jiri
   Bohac switches us from static preallocation of the kdump crashkernel's
   working memory over to dynamic allocation.  So the difficulty of
   a-priori estimation of the second kernel's needs is removed and the
   first kernel obtains extra memory.
 
 - The 5 patch series "generalize panic_print's dump function to be used
   by other kernel parts" from Feng Tang implements some consolidation and
   rationalizatio of the various ways in which a faiing kernel splats
   information at the operator.
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Merge tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:
 "Significant patch series in this pull request:

   - "squashfs: Remove page->mapping references" (Matthew Wilcox) gets
     us closer to being able to remove page->mapping

   - "relayfs: misc changes" (Jason Xing) does some maintenance and
     minor feature addition work in relayfs

   - "kdump: crashkernel reservation from CMA" (Jiri Bohac) switches
     us from static preallocation of the kdump crashkernel's working
     memory over to dynamic allocation. So the difficulty of a-priori
     estimation of the second kernel's needs is removed and the first
     kernel obtains extra memory

   - "generalize panic_print's dump function to be used by other
     kernel parts" (Feng Tang) implements some consolidation and
     rationalization of the various ways in which a failing kernel
     splats information at the operator

* tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (80 commits)
  tools/getdelays: add backward compatibility for taskstats version
  kho: add test for kexec handover
  delaytop: enhance error logging and add PSI feature description
  samples: Kconfig: fix spelling mistake "instancess" -> "instances"
  fat: fix too many log in fat_chain_add()
  scripts/spelling.txt: add notifer||notifier to spelling.txt
  xen/xenbus: fix typo "notifer"
  net: mvneta: fix typo "notifer"
  drm/xe: fix typo "notifer"
  cxl: mce: fix typo "notifer"
  KVM: x86: fix typo "notifer"
  MAINTAINERS: add maintainers for delaytop
  ucount: use atomic_long_try_cmpxchg() in atomic_long_inc_below()
  ucount: fix atomic_long_inc_below() argument type
  kexec: enable CMA based contiguous allocation
  stackdepot: make max number of pools boot-time configurable
  lib/xxhash: remove unused functions
  init/Kconfig: restore CONFIG_BROKEN help text
  lib/raid6: update recov_rvv.c zero page usage
  docs: update docs after introducing delaytop
  ...
 2025-08-03 16:23:09 -07:00
Linus Torvalds
beace86e61 Summary of significant series in this pull request: 
- The 4 patch series "mm: ksm: prevent KSM from breaking merging of new
   VMAs" from Lorenzo Stoakes addresses an issue with KSM's
   PR_SET_MEMORY_MERGE mode: newly mapped VMAs were not eligible for
   merging with existing adjacent VMAs.
 
 - The 4 patch series "mm/damon: introduce DAMON_STAT for simple and
   practical access monitoring" from SeongJae Park adds a new kernel module
   which simplifies the setup and usage of DAMON in production
   environments.
 
 - The 6 patch series "stop passing a writeback_control to swap/shmem
   writeout" from Christoph Hellwig is a cleanup to the writeback code
   which removes a couple of pointers from struct writeback_control.
 
 - The 7 patch series "drivers/base/node.c: optimization and cleanups"
   from Donet Tom contains largely uncorrelated cleanups to the NUMA node
   setup and management code.
 
 - The 4 patch series "mm: userfaultfd: assorted fixes and cleanups" from
   Tal Zussman does some maintenance work on the userfaultfd code.
 
 - The 5 patch series "Readahead tweaks for larger folios" from Ryan
   Roberts implements some tuneups for pagecache readahead when it is
   reading into order>0 folios.
 
 - The 4 patch series "selftests/mm: Tweaks to the cow test" from Mark
   Brown provides some cleanups and consistency improvements to the
   selftests code.
 
 - The 4 patch series "Optimize mremap() for large folios" from Dev Jain
   does that.  A 37% reduction in execution time was measured in a
   memset+mremap+munmap microbenchmark.
 
 - The 5 patch series "Remove zero_user()" from Matthew Wilcox expunges
   zero_user() in favor of the more modern memzero_page().
 
 - The 3 patch series "mm/huge_memory: vmf_insert_folio_*() and
   vmf_insert_pfn_pud() fixes" from David Hildenbrand addresses some warts
   which David noticed in the huge page code.  These were not known to be
   causing any issues at this time.
 
 - The 3 patch series "mm/damon: use alloc_migrate_target() for
   DAMOS_MIGRATE_{HOT,COLD" from SeongJae Park provides some cleanup and
   consolidation work in DAMON.
 
 - The 3 patch series "use vm_flags_t consistently" from Lorenzo Stoakes
   uses vm_flags_t in places where we were inappropriately using other
   types.
 
 - The 3 patch series "mm/memfd: Reserve hugetlb folios before
   allocation" from Vivek Kasireddy increases the reliability of large page
   allocation in the memfd code.
 
 - The 14 patch series "mm: Remove pXX_devmap page table bit and pfn_t
   type" from Alistair Popple removes several now-unneeded PFN_* flags.
 
 - The 5 patch series "mm/damon: decouple sysfs from core" from SeongJae
   Park implememnts some cleanup and maintainability work in the DAMON
   sysfs layer.
 
 - The 5 patch series "madvise cleanup" from Lorenzo Stoakes does quite a
   lot of cleanup/maintenance work in the madvise() code.
 
 - The 4 patch series "madvise anon_name cleanups" from Vlastimil Babka
   provides additional cleanups on top or Lorenzo's effort.
 
 - The 11 patch series "Implement numa node notifier" from Oscar Salvador
   creates a standalone notifier for NUMA node memory state changes.
   Previously these were lumped under the more general memory on/offline
   notifier.
 
 - The 6 patch series "Make MIGRATE_ISOLATE a standalone bit" from Zi Yan
   cleans up the pageblock isolation code and fixes a potential issue which
   doesn't seem to cause any problems in practice.
 
 - The 5 patch series "selftests/damon: add python and drgn based DAMON
   sysfs functionality tests" from SeongJae Park adds additional drgn- and
   python-based DAMON selftests which are more comprehensive than the
   existing selftest suite.
 
 - The 5 patch series "Misc rework on hugetlb faulting path" from Oscar
   Salvador fixes a rather obscure deadlock in the hugetlb fault code and
   follows that fix with a series of cleanups.
 
 - The 3 patch series "cma: factor out allocation logic from
   __cma_declare_contiguous_nid" from Mike Rapoport rationalizes and cleans
   up the highmem-specific code in the CMA allocator.
 
 - The 28 patch series "mm/migration: rework movable_ops page migration
   (part 1)" from David Hildenbrand provides cleanups and
   future-preparedness to the migration code.
 
 - The 2 patch series "mm/damon: add trace events for auto-tuned
   monitoring intervals and DAMOS quota" from SeongJae Park adds some
   tracepoints to some DAMON auto-tuning code.
 
 - The 6 patch series "mm/damon: fix misc bugs in DAMON modules" from
   SeongJae Park does that.
 
 - The 6 patch series "mm/damon: misc cleanups" from SeongJae Park also
   does what it claims.
 
 - The 4 patch series "mm: folio_pte_batch() improvements" from David
   Hildenbrand cleans up the large folio PTE batching code.
 
 - The 13 patch series "mm/damon/vaddr: Allow interleaving in
   migrate_{hot,cold} actions" from SeongJae Park facilitates dynamic
   alteration of DAMON's inter-node allocation policy.
 
 - The 3 patch series "Remove unmap_and_put_page()" from Vishal Moola
   provides a couple of page->folio conversions.
 
 - The 4 patch series "mm: per-node proactive reclaim" from Davidlohr
   Bueso implements a per-node control of proactive reclaim - beyond the
   current memcg-based implementation.
 
 - The 14 patch series "mm/damon: remove damon_callback" from SeongJae
   Park replaces the damon_callback interface with a more general and
   powerful damon_call()+damos_walk() interface.
 
 - The 10 patch series "mm/mremap: permit mremap() move of multiple VMAs"
   from Lorenzo Stoakes implements a number of mremap cleanups (of course)
   in preparation for adding new mremap() functionality: newly permit the
   remapping of multiple VMAs when the user is specifying MREMAP_FIXED.  It
   still excludes some specialized situations where this cannot be
   performed reliably.
 
 - The 3 patch series "drop hugetlb_free_pgd_range()" from Anthony Yznaga
   switches some sparc hugetlb code over to the generic version and removes
   the thus-unneeded hugetlb_free_pgd_range().
 
 - The 4 patch series "mm/damon/sysfs: support periodic and automated
   stats update" from SeongJae Park augments the present
   userspace-requested update of DAMON sysfs monitoring files.  Automatic
   update is now provided, along with a tunable to control the update
   interval.
 
 - The 4 patch series "Some randome fixes and cleanups to swapfile" from
   Kemeng Shi does what is claims.
 
 - The 4 patch series "mm: introduce snapshot_page" from Luiz Capitulino
   and David Hildenbrand provides (and uses) a means by which debug-style
   functions can grab a copy of a pageframe and inspect it locklessly
   without tripping over the races inherent in operating on the live
   pageframe directly.
 
 - The 6 patch series "use per-vma locks for /proc/pid/maps reads" from
   Suren Baghdasaryan addresses the large contention issues which can be
   triggered by reads from that procfs file.  Latencies are reduced by more
   than half in some situations.  The series also introduces several new
   selftests for the /proc/pid/maps interface.
 
 - The 6 patch series "__folio_split() clean up" from Zi Yan cleans up
   __folio_split()!
 
 - The 7 patch series "Optimize mprotect() for large folios" from Dev
   Jain provides some quite large (>3x) speedups to mprotect() when dealing
   with large folios.
 
 - The 2 patch series "selftests/mm: reuse FORCE_READ to replace "asm
   volatile("" : "+r" (XXX));" and some cleanup" from wang lian does some
   cleanup work in the selftests code.
 
 - The 3 patch series "tools/testing: expand mremap testing" from Lorenzo
   Stoakes extends the mremap() selftest in several ways, including adding
   more checking of Lorenzo's recently added "permit mremap() move of
   multiple VMAs" feature.
 
 - The 22 patch series "selftests/damon/sysfs.py: test all parameters"
   from SeongJae Park extends the DAMON sysfs interface selftest so that it
   tests all possible user-requested parameters.  Rather than the present
   minimal subset.
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Merge tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:
 "As usual, many cleanups. The below blurbiage describes 42 patchsets.
  21 of those are partially or fully cleanup work. "cleans up",
  "cleanup", "maintainability", "rationalizes", etc.

  I never knew the MM code was so dirty.

  "mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes)
     addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly
     mapped VMAs were not eligible for merging with existing adjacent
     VMAs.

  "mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park)
     adds a new kernel module which simplifies the setup and usage of
     DAMON in production environments.

  "stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig)
     is a cleanup to the writeback code which removes a couple of
     pointers from struct writeback_control.

  "drivers/base/node.c: optimization and cleanups" (Donet Tom)
     contains largely uncorrelated cleanups to the NUMA node setup and
     management code.

  "mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman)
     does some maintenance work on the userfaultfd code.

  "Readahead tweaks for larger folios" (Ryan Roberts)
     implements some tuneups for pagecache readahead when it is reading
     into order>0 folios.

  "selftests/mm: Tweaks to the cow test" (Mark Brown)
     provides some cleanups and consistency improvements to the
     selftests code.

  "Optimize mremap() for large folios" (Dev Jain)
     does that. A 37% reduction in execution time was measured in a
     memset+mremap+munmap microbenchmark.

  "Remove zero_user()" (Matthew Wilcox)
     expunges zero_user() in favor of the more modern memzero_page().

  "mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand)
     addresses some warts which David noticed in the huge page code.
     These were not known to be causing any issues at this time.

  "mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park)
     provides some cleanup and consolidation work in DAMON.

  "use vm_flags_t consistently" (Lorenzo Stoakes)
     uses vm_flags_t in places where we were inappropriately using other
     types.

  "mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy)
     increases the reliability of large page allocation in the memfd
     code.

  "mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple)
     removes several now-unneeded PFN_* flags.

  "mm/damon: decouple sysfs from core" (SeongJae Park)
     implememnts some cleanup and maintainability work in the DAMON
     sysfs layer.

  "madvise cleanup" (Lorenzo Stoakes)
     does quite a lot of cleanup/maintenance work in the madvise() code.

  "madvise anon_name cleanups" (Vlastimil Babka)
     provides additional cleanups on top or Lorenzo's effort.

  "Implement numa node notifier" (Oscar Salvador)
     creates a standalone notifier for NUMA node memory state changes.
     Previously these were lumped under the more general memory
     on/offline notifier.

  "Make MIGRATE_ISOLATE a standalone bit" (Zi Yan)
     cleans up the pageblock isolation code and fixes a potential issue
     which doesn't seem to cause any problems in practice.

  "selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park)
     adds additional drgn- and python-based DAMON selftests which are
     more comprehensive than the existing selftest suite.

  "Misc rework on hugetlb faulting path" (Oscar Salvador)
     fixes a rather obscure deadlock in the hugetlb fault code and
     follows that fix with a series of cleanups.

  "cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport)
     rationalizes and cleans up the highmem-specific code in the CMA
     allocator.

  "mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand)
     provides cleanups and future-preparedness to the migration code.

  "mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park)
     adds some tracepoints to some DAMON auto-tuning code.

  "mm/damon: fix misc bugs in DAMON modules" (SeongJae Park)
     does that.

  "mm/damon: misc cleanups" (SeongJae Park)
     also does what it claims.

  "mm: folio_pte_batch() improvements" (David Hildenbrand)
     cleans up the large folio PTE batching code.

  "mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park)
     facilitates dynamic alteration of DAMON's inter-node allocation
     policy.

  "Remove unmap_and_put_page()" (Vishal Moola)
     provides a couple of page->folio conversions.

  "mm: per-node proactive reclaim" (Davidlohr Bueso)
     implements a per-node control of proactive reclaim - beyond the
     current memcg-based implementation.

  "mm/damon: remove damon_callback" (SeongJae Park)
     replaces the damon_callback interface with a more general and
     powerful damon_call()+damos_walk() interface.

  "mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes)
     implements a number of mremap cleanups (of course) in preparation
     for adding new mremap() functionality: newly permit the remapping
     of multiple VMAs when the user is specifying MREMAP_FIXED. It still
     excludes some specialized situations where this cannot be performed
     reliably.

  "drop hugetlb_free_pgd_range()" (Anthony Yznaga)
     switches some sparc hugetlb code over to the generic version and
     removes the thus-unneeded hugetlb_free_pgd_range().

  "mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park)
     augments the present userspace-requested update of DAMON sysfs
     monitoring files. Automatic update is now provided, along with a
     tunable to control the update interval.

  "Some randome fixes and cleanups to swapfile" (Kemeng Shi)
     does what is claims.

  "mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand)
     provides (and uses) a means by which debug-style functions can grab
     a copy of a pageframe and inspect it locklessly without tripping
     over the races inherent in operating on the live pageframe
     directly.

  "use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan)
     addresses the large contention issues which can be triggered by
     reads from that procfs file. Latencies are reduced by more than
     half in some situations. The series also introduces several new
     selftests for the /proc/pid/maps interface.

  "__folio_split() clean up" (Zi Yan)
     cleans up __folio_split()!

  "Optimize mprotect() for large folios" (Dev Jain)
     provides some quite large (>3x) speedups to mprotect() when dealing
     with large folios.

  "selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian)
     does some cleanup work in the selftests code.

  "tools/testing: expand mremap testing" (Lorenzo Stoakes)
     extends the mremap() selftest in several ways, including adding
     more checking of Lorenzo's recently added "permit mremap() move of
     multiple VMAs" feature.

  "selftests/damon/sysfs.py: test all parameters" (SeongJae Park)
     extends the DAMON sysfs interface selftest so that it tests all
     possible user-requested parameters. Rather than the present minimal
     subset"

* tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits)
  MAINTAINERS: add missing headers to mempory policy & migration section
  MAINTAINERS: add missing file to cgroup section
  MAINTAINERS: add MM MISC section, add missing files to MISC and CORE
  MAINTAINERS: add missing zsmalloc file
  MAINTAINERS: add missing files to page alloc section
  MAINTAINERS: add missing shrinker files
  MAINTAINERS: move memremap.[ch] to hotplug section
  MAINTAINERS: add missing mm_slot.h file THP section
  MAINTAINERS: add missing interval_tree.c to memory mapping section
  MAINTAINERS: add missing percpu-internal.h file to per-cpu section
  mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info()
  selftests/damon: introduce _common.sh to host shared function
  selftests/damon/sysfs.py: test runtime reduction of DAMON parameters
  selftests/damon/sysfs.py: test non-default parameters runtime commit
  selftests/damon/sysfs.py: generalize DAMON context commit assertion
  selftests/damon/sysfs.py: generalize monitoring attributes commit assertion
  selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion
  selftests/damon/sysfs.py: test DAMOS filters commitment
  selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion
  selftests/damon/sysfs.py: test DAMOS destinations commitment
  ...
 2025-07-31 14:57:54 -07:00
Linus Torvalds
8e736a2eea hardening updates for v6.17-rc1 
- Introduce and start using TRAILING_OVERLAP() helper for fixing
   embedded flex array instances (Gustavo A. R. Silva)
 
 - mux: Convert mux_control_ops to a flex array member in mux_chip
   (Thorsten Blum)
 
 - string: Group str_has_prefix() and strstarts() (Andy Shevchenko)
 
 - Remove KCOV instrumentation from __init and __head (Ritesh Harjani,
   Kees Cook)
 
 - Refactor and rename stackleak feature to support Clang
 
 - Add KUnit test for seq_buf API
 
 - Fix KUnit fortify test under LTO
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Merge tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull hardening updates from Kees Cook:

 - Introduce and start using TRAILING_OVERLAP() helper for fixing
   embedded flex array instances (Gustavo A. R. Silva)

 - mux: Convert mux_control_ops to a flex array member in mux_chip
   (Thorsten Blum)

 - string: Group str_has_prefix() and strstarts() (Andy Shevchenko)

 - Remove KCOV instrumentation from __init and __head (Ritesh Harjani,
   Kees Cook)

 - Refactor and rename stackleak feature to support Clang

 - Add KUnit test for seq_buf API

 - Fix KUnit fortify test under LTO

* tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (22 commits)
  sched/task_stack: Add missing const qualifier to end_of_stack()
  kstack_erase: Support Clang stack depth tracking
  kstack_erase: Add -mgeneral-regs-only to silence Clang warnings
  init.h: Disable sanitizer coverage for __init and __head
  kstack_erase: Disable kstack_erase for all of arm compressed boot code
  x86: Handle KCOV __init vs inline mismatches
  arm64: Handle KCOV __init vs inline mismatches
  s390: Handle KCOV __init vs inline mismatches
  arm: Handle KCOV __init vs inline mismatches
  mips: Handle KCOV __init vs inline mismatch
  powerpc/mm/book3s64: Move kfence and debug_pagealloc related calls to __init section
  configs/hardening: Enable CONFIG_INIT_ON_FREE_DEFAULT_ON
  configs/hardening: Enable CONFIG_KSTACK_ERASE
  stackleak: Split KSTACK_ERASE_CFLAGS from GCC_PLUGINS_CFLAGS
  stackleak: Rename stackleak_track_stack to __sanitizer_cov_stack_depth
  stackleak: Rename STACKLEAK to KSTACK_ERASE
  seq_buf: Introduce KUnit tests
  string: Group str_has_prefix() and strstarts()
  kunit/fortify: Add back "volatile" for sizeof() constants
  acpi: nfit: intel: avoid multiple -Wflex-array-member-not-at-end warnings
  ...
 2025-07-28 17:16:12 -07:00
Linus Torvalds
f70d24c230 vfs-6.17-rc1.nsfs 
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Merge tag 'vfs-6.17-rc1.nsfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull namespace updates from Christian Brauner:
 "This contains namespace updates. This time specifically for nsfs:

   - Userspace heavily relies on the root inode numbers for namespaces
     to identify the initial namespaces. That's already a hard
     dependency. So we cannot change that anymore. Move the initial
     inode numbers to a public header and align the only two namespaces
     that currently don't do that with all the other namespaces.

   - The root inode of /proc having a fixed inode number has been part
     of the core kernel ABI since its inception, and recently some
     userspace programs (mainly container runtimes) have started to
     explicitly depend on this behaviour.

     The main reason this is useful to userspace is that by checking
     that a suspect /proc handle has fstype PROC_SUPER_MAGIC and is
     PROCFS_ROOT_INO, they can then use openat2() together with
     RESOLVE_{NO_{XDEV,MAGICLINK},BENEATH} to ensure that there isn't a
     bind-mount that replaces some procfs file with a different one.

     This kind of attack has lead to security issues in container
     runtimes in the past (such as CVE-2019-19921) and libraries like
     libpathrs[1] use this feature of procfs to provide safe procfs
     handling functions"

* tag 'vfs-6.17-rc1.nsfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  uapi: export PROCFS_ROOT_INO
  mntns: use stable inode number for initial mount ns
  netns: use stable inode number for initial mount ns
  nsfs: move root inode number to uapi
 2025-07-28 12:50:56 -07:00
Linus Torvalds
7879d7aff0 vfs-6.17-rc1.misc 
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Merge tag 'vfs-6.17-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull misc VFS updates from Christian Brauner:
 "This contains the usual selections of misc updates for this cycle.

  Features:

   - Add ext4 IOCB_DONTCACHE support

     This refactors the address_space_operations write_begin() and
     write_end() callbacks to take const struct kiocb * as their first
     argument, allowing IOCB flags such as IOCB_DONTCACHE to propagate
     to the filesystem's buffered I/O path.

     Ext4 is updated to implement handling of the IOCB_DONTCACHE flag
     and advertises support via the FOP_DONTCACHE file operation flag.

     Additionally, the i915 driver's shmem write paths are updated to
     bypass the legacy write_begin/write_end interface in favor of
     directly calling write_iter() with a constructed synchronous kiocb.
     Another i915 change replaces a manual write loop with
     kernel_write() during GEM shmem object creation.

  Cleanups:

   - don't duplicate vfs_open() in kernel_file_open()

   - proc_fd_getattr(): don't bother with S_ISDIR() check

   - fs/ecryptfs: replace snprintf with sysfs_emit in show function

   - vfs: Remove unnecessary list_for_each_entry_safe() from
     evict_inodes()

   - filelock: add new locks_wake_up_waiter() helper

   - fs: Remove three arguments from block_write_end()

   - VFS: change old_dir and new_dir in struct renamedata to dentrys

   - netfs: Remove unused declaration netfs_queue_write_request()

  Fixes:

   - eventpoll: Fix semi-unbounded recursion

   - eventpoll: fix sphinx documentation build warning

   - fs/read_write: Fix spelling typo

   - fs: annotate data race between poll_schedule_timeout() and
     pollwake()

   - fs/pipe: set FMODE_NOWAIT in create_pipe_files()

   - docs/vfs: update references to i_mutex to i_rwsem

   - fs/buffer: remove comment about hard sectorsize

   - fs/buffer: remove the min and max limit checks in __getblk_slow()

   - fs/libfs: don't assume blocksize <= PAGE_SIZE in
     generic_check_addressable

   - fs_context: fix parameter name in infofc() macro

   - fs: Prevent file descriptor table allocations exceeding INT_MAX"

* tag 'vfs-6.17-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (24 commits)
  netfs: Remove unused declaration netfs_queue_write_request()
  eventpoll: fix sphinx documentation build warning
  ext4: support uncached buffered I/O
  mm/pagemap: add write_begin_get_folio() helper function
  fs: change write_begin/write_end interface to take struct kiocb *
  drm/i915: Refactor shmem_pwrite() to use kiocb and write_iter
  drm/i915: Use kernel_write() in shmem object create
  eventpoll: Fix semi-unbounded recursion
  vfs: Remove unnecessary list_for_each_entry_safe() from evict_inodes()
  fs/libfs: don't assume blocksize <= PAGE_SIZE in generic_check_addressable
  fs/buffer: remove the min and max limit checks in __getblk_slow()
  fs: Prevent file descriptor table allocations exceeding INT_MAX
  fs: Remove three arguments from block_write_end()
  fs/ecryptfs: replace snprintf with sysfs_emit in show function
  fs: annotate suspected data race between poll_schedule_timeout() and pollwake()
  docs/vfs: update references to i_mutex to i_rwsem
  fs/buffer: remove comment about hard sectorsize
  fs_context: fix parameter name in infofc() macro
  VFS: change old_dir and new_dir in struct renamedata to dentrys
  proc_fd_getattr(): don't bother with S_ISDIR() check
  ...
 2025-07-28 11:22:56 -07:00
Linus Torvalds
11fe69fbd5 Current exclusion rules for ->d_flags stores are rather unpleasant. 
The basic rules are simple:
 	* stores to dentry->d_flags are OK under dentry->d_lock.
 	* stores to dentry->d_flags are OK in the dentry constructor, before
 becomes potentially visible to other threads.
 Unfortunately, there's a couple of exceptions to that, and that's where the
 headache comes from.
 
 	Main PITA comes from d_set_d_op(); that primitive sets ->d_op
 of dentry and adjusts the flags that correspond to presence of individual
 methods.  It's very easy to misuse; existing uses _are_ safe, but proof
 of correctness is brittle.
 
 	Use in __d_alloc() is safe (we are within a constructor), but we
 might as well precalculate the initial value of ->d_flags when we set
 the default ->d_op for given superblock and set ->d_flags directly
 instead of messing with that helper.
 
 	The reasons why other uses are safe are bloody convoluted; I'm not going
 to reproduce it here.  See https://lore.kernel.org/all/20250224010624.GT1977892@ZenIV/
 for gory details, if you care.  The critical part is using d_set_d_op() only
 just prior to d_splice_alias(), which makes a combination of d_splice_alias()
 with setting ->d_op, etc. a natural replacement primitive.  Better yet, if
 we go that way, it's easy to take setting ->d_op and modifying ->d_flags
 under ->d_lock, which eliminates the headache as far as ->d_flags exclusion
 rules are concerned.  Other exceptions are minor and easy to deal with.
 
 	What this series does:
 * d_set_d_op() is no longer available; new primitive (d_splice_alias_ops())
 is provided, equivalent to combination of d_set_d_op() and d_splice_alias().
 * new field of struct super_block - ->s_d_flags.  Default value of ->d_flags
 to be used when allocating dentries on this filesystem.
 * new primitive for setting ->s_d_op: set_default_d_op().  Replaces stores
 to ->s_d_op at mount time.  All in-tree filesystems converted; out-of-tree
 ones will get caught by compiler (->s_d_op is renamed, so stores to it will
 be caught).  ->s_d_flags is set by the same primitive to match the ->s_d_op.
 * a lot of filesystems had ->s_d_op->d_delete equal to always_delete_dentry;
 that is equivalent to setting DCACHE_DONTCACHE in ->d_flags, so such filesystems
 can bloody well set that bit in ->s_d_flags and drop ->d_delete() from
 dentry_operations.  In quite a few cases that results in empty dentry_operations,
 which means that we can get rid of those.
 * kill simple_dentry_operations - not needed anymore.
 * massage d_alloc_parallel() to get rid of the other exception wrt ->d_flags
 stores - we can set DCACHE_PAR_LOOKUP as soon as we allocate the new dentry;
 no need to delay that until we commit to using the sucker.
 
 As the result, ->d_flags stores are all either under ->d_lock or done before
 the dentry becomes visible in any shared data structures.
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Merge tag 'pull-dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull dentry d_flags updates from Al Viro:
 "The current exclusion rules for dentry->d_flags stores are rather
  unpleasant. The basic rules are simple:

   - stores to dentry->d_flags are OK under dentry->d_lock

   - stores to dentry->d_flags are OK in the dentry constructor, before
     becomes potentially visible to other threads

  Unfortunately, there's a couple of exceptions to that, and that's
  where the headache comes from.

  The main PITA comes from d_set_d_op(); that primitive sets ->d_op of
  dentry and adjusts the flags that correspond to presence of individual
  methods. It's very easy to misuse; existing uses _are_ safe, but proof
  of correctness is brittle.

  Use in __d_alloc() is safe (we are within a constructor), but we might
  as well precalculate the initial value of 'd_flags' when we set the
  default ->d_op for given superblock and set 'd_flags' directly instead
  of messing with that helper.

  The reasons why other uses are safe are bloody convoluted; I'm not
  going to reproduce it here. See [1] for gory details, if you care. The
  critical part is using d_set_d_op() only just prior to
  d_splice_alias(), which makes a combination of d_splice_alias() with
  setting ->d_op, etc a natural replacement primitive.

  Better yet, if we go that way, it's easy to take setting ->d_op and
  modifying 'd_flags' under ->d_lock, which eliminates the headache as
  far as 'd_flags' exclusion rules are concerned. Other exceptions are
  minor and easy to deal with.

  What this series does:

   - d_set_d_op() is no longer available; instead a new primitive
     (d_splice_alias_ops()) is provided, equivalent to combination of
     d_set_d_op() and d_splice_alias().

   - new field of struct super_block - 's_d_flags'. This sets the
     default value of 'd_flags' to be used when allocating dentries on
     this filesystem.

   - new primitive for setting 's_d_op': set_default_d_op(). This
     replaces stores to 's_d_op' at mount time.

     All in-tree filesystems converted; out-of-tree ones will get caught
     by the compiler ('s_d_op' is renamed, so stores to it will be
     caught). 's_d_flags' is set by the same primitive to match the
     's_d_op'.

   - a lot of filesystems had sb->s_d_op->d_delete equal to
     always_delete_dentry; that is equivalent to setting
     DCACHE_DONTCACHE in 'd_flags', so such filesystems can bloody well
     set that bit in 's_d_flags' and drop 'd_delete()' from
     dentry_operations.

     In quite a few cases that results in empty dentry_operations, which
     means that we can get rid of those.

   - kill simple_dentry_operations - not needed anymore

   - massage d_alloc_parallel() to get rid of the other exception wrt
     'd_flags' stores - we can set DCACHE_PAR_LOOKUP as soon as we
     allocate the new dentry; no need to delay that until we commit to
     using the sucker.

  As the result, 'd_flags' stores are all either under ->d_lock or done
  before the dentry becomes visible in any shared data structures"

Link: https://lore.kernel.org/all/20250224010624.GT1977892@ZenIV/ [1]

* tag 'pull-dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (21 commits)
  configfs: use DCACHE_DONTCACHE
  debugfs: use DCACHE_DONTCACHE
  efivarfs: use DCACHE_DONTCACHE instead of always_delete_dentry()
  9p: don't bother with always_delete_dentry
  ramfs, hugetlbfs, mqueue: set DCACHE_DONTCACHE
  kill simple_dentry_operations
  devpts, sunrpc, hostfs: don't bother with ->d_op
  shmem: no dentry retention past the refcount reaching zero
  d_alloc_parallel(): set DCACHE_PAR_LOOKUP earlier
  make d_set_d_op() static
  simple_lookup(): just set DCACHE_DONTCACHE
  tracefs: Add d_delete to remove negative dentries
  set_default_d_op(): calculate the matching value for ->d_flags
  correct the set of flags forbidden at d_set_d_op() time
  split d_flags calculation out of d_set_d_op()
  new helper: set_default_d_op()
  fuse: no need for special dentry_operations for root dentry
  switch procfs from d_set_d_op() to d_splice_alias_ops()
  new helper: d_splice_alias_ops()
  procfs: kill ->proc_dops
  ...
 2025-07-28 09:17:57 -07:00
Suren Baghdasaryan
5631da56c9 fs/proc/task_mmu: read proc/pid/maps under per-vma lock 
With maple_tree supporting vma tree traversal under RCU and per-vma locks,
/proc/pid/maps can be read while holding individual vma locks instead of
locking the entire address space.

A completely lockless approach (walking vma tree under RCU) would be quite
complex with the main issue being get_vma_name() using callbacks which
might not work correctly with a stable vma copy, requiring original
(unstable) vma - see special_mapping_name() for example.

When per-vma lock acquisition fails, we take the mmap_lock for reading,
lock the vma, release the mmap_lock and continue.  This fallback to mmap
read lock guarantees the reader to make forward progress even during lock
contention.  This will interfere with the writer but for a very short time
while we are acquiring the per-vma lock and only when there was contention
on the vma reader is interested in.

We shouldn't see a repeated fallback to mmap read locks in practice, as
this require a very unlikely series of lock contentions (for instance due
to repeated vma split operations).  However even if this did somehow
happen, we would still progress.

One case requiring special handling is when a vma changes between the time
it was found and the time it got locked.  A problematic case would be if a
vma got shrunk so that its vm_start moved higher in the address space and
a new vma was installed at the beginning:

reader found:               |--------VMA A--------|
VMA is modified:            |-VMA B-|----VMA A----|
reader locks modified VMA A
reader reports VMA A:       |  gap  |----VMA A----|

This would result in reporting a gap in the address space that does not
exist.  To prevent this we retry the lookup after locking the vma, however
we do that only when we identify a gap and detect that the address space
was changed after we found the vma.

This change is designed to reduce mmap_lock contention and prevent a
process reading /proc/pid/maps files (often a low priority task, such as
monitoring/data collection services) from blocking address space updates. 
Note that this change has a userspace visible disadvantage: it allows for
sub-page data tearing as opposed to the previous mechanism where data
tearing could happen only between pages of generated output data.  Since
current userspace considers data tearing between pages to be acceptable,
we assume is will be able to handle sub-page data tearing as well.

Link: https://lkml.kernel.org/r/20250719182854.3166724-7-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jeongjun Park <aha310510@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Weißschuh <linux@weissschuh.net>
Cc: T.J. Mercier <tjmercier@google.com>
Cc: Ye Bin <yebin10@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-07-24 19:12:37 -07:00
Suren Baghdasaryan
03d98703f7 fs/proc/task_mmu: remove conversion of seq_file position to unsigned 
Back in 2.6 era, last_addr used to be stored in seq_file->version
variable, which was unsigned long.  As a result, sentinels to represent
gate vma and end of all vmas used unsigned values.  In more recent kernels
we don't used seq_file->version anymore and therefore conversion from
loff_t into unsigned type is not needed.  Similarly, sentinel values don't
need to be unsigned.  Remove type conversion for set_file position and
change sentinel values to signed.  While at it, change the hardcoded
sentinel values with named definitions for better documentation.

Link: https://lkml.kernel.org/r/20250719182854.3166724-6-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Jann Horn <jannh@google.com>
Cc: Jeongjun Park <aha310510@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Weißschuh <linux@weissschuh.net>
Cc: T.J. Mercier <tjmercier@google.com>
Cc: Ye Bin <yebin10@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-07-24 19:12:37 -07:00
Luiz Capitulino
476d87d6a0 fs: stable_page_flags(): use snapshot_page() 
A race condition is possible in stable_page_flags() where user-space is
reading /proc/kpageflags concurrently to a folio split.  This may lead to
oopses or BUG_ON()s being triggered.

To fix this, this commit uses snapshot_page() in stable_page_flags() so
that stable_page_flags() works with a stable page and folio snapshots
instead.

Note that stable_page_flags() makes use of some functions that require the
original page or folio pointer to work properly (eg.  is_free_budy_page()
and folio_test_idle()).  Since those functions can't be used on the page
snapshot, we replace their usage with flags that were set by
snapshot_page() for this purpose.

Link: https://lkml.kernel.org/r/52c16c0f00995a812a55980c2f26848a999a34ab.1752499009.git.luizcap@redhat.com
Signed-off-by: Luiz Capitulino <luizcap@redhat.com>
Reviewed-by: Shivank Garg <shivankg@amd.com>
Tested-by: Harry Yoo <harry.yoo@oracle.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-07-24 19:12:35 -07:00
Luiz Capitulino
71f2a2c4ff proc: kpagecount: use snapshot_page() 
Currently, the call to folio_precise_page_mapcount() from kpage_read() can
race with a folio split.  When the race happens we trigger a
VM_BUG_ON_FOLIO() in folio_entire_mapcount() (see splat below).

This commit fixes this race by using snapshot_page() so that we retrieve
the folio mapcount using a folio snapshot.

[ 2356.558576] page: refcount:1 mapcount:1 mapping:0000000000000000 index:0xffff85200 pfn:0x6f7c00
[ 2356.558748] memcg:ffff000651775780
[ 2356.558763] anon flags: 0xafffff60020838(uptodate|dirty|lru|owner_2|swapbacked|node=1|zone=2|lastcpupid=0xfffff)
[ 2356.558796] raw: 00afffff60020838 fffffdffdb5d0048 fffffdffdadf7fc8 ffff00064c1629c1
[ 2356.558817] raw: 0000000ffff85200 0000000000000000 0000000100000000 ffff000651775780
[ 2356.558839] page dumped because: VM_BUG_ON_FOLIO(!folio_test_large(folio))
[ 2356.558882] ------------[ cut here ]------------
[ 2356.558897] kernel BUG at ./include/linux/mm.h:1103!
[ 2356.558982] Internal error: Oops - BUG: 00000000f2000800 [#1]  SMP
[ 2356.564729] CPU: 8 UID: 0 PID: 1864 Comm: folio-split-rac Tainted: G S      W           6.15.0+ #3 PREEMPT(voluntary)
[ 2356.566196] Tainted: [S]=CPU_OUT_OF_SPEC, [W]=WARN
[ 2356.566814] Hardware name: Red Hat KVM, BIOS edk2-20241117-3.el9 11/17/2024
[ 2356.567684] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 2356.568563] pc : kpage_read.constprop.0+0x26c/0x290
[ 2356.569605] lr : kpage_read.constprop.0+0x26c/0x290
[ 2356.569992] sp : ffff80008fb739b0
[ 2356.570263] x29: ffff80008fb739b0 x28: ffff00064aa69580 x27: 00000000ff000000
[ 2356.570842] x26: 0000fffffffffff8 x25: ffff00064aa69580 x24: ffff80008fb73ae0
[ 2356.571411] x23: 0000000000000001 x22: 0000ffff86c6e8b8 x21: 0000000000000008
[ 2356.571978] x20: 00000000006f7c00 x19: 0000ffff86c6e8b8 x18: 0000000000000000
[ 2356.572581] x17: 3630303066666666 x16: 0000000000000003 x15: 0000000000001000
[ 2356.573217] x14: 00000000ffffffff x13: 0000000000000004 x12: 00aaaaaa00aaaaaa
[ 2356.577674] x11: 0000000000000000 x10: 00aaaaaa00aaaaaa x9 : ffffbf3afca6c300
[ 2356.578332] x8 : 0000000000000002 x7 : 0000000000000001 x6 : 0000000000000001
[ 2356.578984] x5 : ffff000c79812408 x4 : 0000000000000000 x3 : 0000000000000000
[ 2356.579635] x2 : 0000000000000000 x1 : ffff00064aa69580 x0 : 000000000000003e
[ 2356.580286] Call trace:
[ 2356.580524]  kpage_read.constprop.0+0x26c/0x290 (P)
[ 2356.580982]  kpagecount_read+0x28/0x40
[ 2356.581336]  proc_reg_read+0x38/0x100
[ 2356.581681]  vfs_read+0xcc/0x320
[ 2356.581992]  ksys_read+0x74/0x118
[ 2356.582306]  __arm64_sys_read+0x24/0x38
[ 2356.582668]  invoke_syscall+0x70/0x100
[ 2356.583022]  el0_svc_common.constprop.0+0x48/0xf8
[ 2356.583456]  do_el0_svc+0x28/0x40
[ 2356.583930]  el0_svc+0x38/0x118
[ 2356.584328]  el0t_64_sync_handler+0x144/0x168
[ 2356.584883]  el0t_64_sync+0x19c/0x1a0
[ 2356.585350] Code: aa0103e0 9003a541 91082021 97f813fc (d4210000)
[ 2356.586130] ---[ end trace 0000000000000000 ]---
[ 2356.587377] note: folio-split-rac[1864] exited with irqs disabled
[ 2356.588050] note: folio-split-rac[1864] exited with preempt_count 1

Link: https://lkml.kernel.org/r/1c05cc725b90962d56323ff2e28e9cc3ae397b68.1752499009.git.luizcap@redhat.com
Signed-off-by: Luiz Capitulino <luizcap@redhat.com>
Reported-by: syzbot+3d7dc5eaba6b932f8535@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/67812fbd.050a0220.d0267.0030.GAE@google.com/Reviewed-by: Shivank Garg <shivankg@amd.com>
Tested-by: Harry Yoo <harry.yoo@oracle.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-07-24 19:12:35 -07:00
Kees Cook
57fbad15c2 stackleak: Rename STACKLEAK to KSTACK_ERASE 
In preparation for adding Clang sanitizer coverage stack depth tracking
that can support stack depth callbacks:

- Add the new top-level CONFIG_KSTACK_ERASE option which will be
  implemented either with the stackleak GCC plugin, or with the Clang
  stack depth callback support.
- Rename CONFIG_GCC_PLUGIN_STACKLEAK as needed to CONFIG_KSTACK_ERASE,
  but keep it for anything specific to the GCC plugin itself.
- Rename all exposed "STACKLEAK" names and files to "KSTACK_ERASE" (named
  for what it does rather than what it protects against), but leave as
  many of the internals alone as possible to avoid even more churn.

While here, also split "prev_lowest_stack" into CONFIG_KSTACK_ERASE_METRICS,
since that's the only place it is referenced from.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250717232519.2984886-1-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
 2025-07-21 21:35:01 -07:00
Vlastimil Babka
8356a5a3b0 mm, vmstat: remove the NR_WRITEBACK_TEMP node_stat_item counter 
The only user of the counter (FUSE) was removed in commit 0c58a97f91
("fuse: remove tmp folio for writebacks and internal rb tree") so follow
the established pattern of removing the counter and hardcoding 0 in
meminfo output, as done recently with NR_BOUNCE.  Update documentation for
procfs, including for the value for Bounce that was missed when removing
its counter.

Also remove the mention of NR_WRITEBACK_TEMP implications from a comment
in wb_position_ratio(). The rest of the comment there about fuse setting
bdi->max_ratio to 1% is still correct.

[vbabka@suse.cz: v2]
  Link: https://lkml.kernel.org/r/5a848e15-6a57-4ecb-a015-d4f358b8a5d3@suse.cz
Link: https://lkml.kernel.org/r/20250625-nr_writeback_removal-v1-1-7f2a0df70faa@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jeffle Xu <jefflexu@linux.alibaba.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joanne Koong <joannelkoong@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shuemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Maxim Patlasov <mpatlasov@parallels.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zach O'Keefe <zokeefe@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-07-19 18:59:47 -07:00
David Hildenbrand
df25569d40 mm: rename PAGE_MAPPING_* to FOLIO_MAPPING_* 
Now that the mapping flags are only used for folios, let's rename the
defines.

Link: https://lkml.kernel.org/r/20250704102524.326966-27-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Eugenio Pé rez <eperezma@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Gregory Price <gourry@gourry.net>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Jerrin Shaji George <jerrin.shaji-george@broadcom.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mathew Brost <matthew.brost@intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-07-13 16:38:31 -07:00
Andrew Morton
cac3d177c0 Merge branch 'mm-hotfixes-stable' into mm-stable to pick up changes which 
are required for a merge of the series "mm: folio_pte_batch()
improvements".
 2025-07-12 14:48:26 -07:00
Aleksa Sarai
76fdb7eb4e
uapi: export PROCFS_ROOT_INO 
The root inode of /proc having a fixed inode number has been part of the
core kernel ABI since its inception, and recently some userspace
programs (mainly container runtimes) have started to explicitly depend
on this behaviour.

The main reason this is useful to userspace is that by checking that a
suspect /proc handle has fstype PROC_SUPER_MAGIC and is PROCFS_ROOT_INO,
they can then use openat2(RESOLVE_{NO_{XDEV,MAGICLINK},BENEATH}) to
ensure that there isn't a bind-mount that replaces some procfs file with
a different one. This kind of attack has lead to security issues in
container runtimes in the past (such as CVE-2019-19921) and libraries
like libpathrs[1] use this feature of procfs to provide safe procfs
handling functions.

There was also some trailing whitespace in the "struct proc_dir_entry"
initialiser, so fix that up as well.

[1]: https://github.com/openSUSE/libpathrs

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Link: https://lore.kernel.org/20250708-uapi-procfs-root-ino-v1-1-6ae61e97c79b@cyphar.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2025-07-10 09:39:18 +02:00
Su Hui
ad0039db42 fs/proc/vmcore: a few cleanups for vmcore_add_device_dump() 
There are two cleanups for vmcore_add_device_dump().  Return -ENOMEM
directly rather than goto the label to simplify the code and use
scoped_guard() to simplify the lock/unlock code.

Link: https://lkml.kernel.org/r/20250626105440.1053139-1-suhui@nfschina.com
Signed-off-by: Su Hui <suhui@nfschina.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Suhui <suhui@nfschina.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-07-09 22:57:56 -07:00
wangzijie
ff7ec8dc1b proc: use the same treatment to check proc_lseek as ones for proc_read_iter et.al 
Check pde->proc_ops->proc_lseek directly may cause UAF in rmmod scenario. 
It's a gap in proc_reg_open() after commit 654b33ada4ab("proc: fix UAF in
proc_get_inode()").  Followed by AI Viro's suggestion, fix it in same
manner.

Link: https://lkml.kernel.org/r/20250607021353.1127963-1-wangzijie1@honor.com
Fixes: 3f61631d47 ("take care to handle NULL ->proc_lseek()")
Signed-off-by: wangzijie <wangzijie1@honor.com>
Reviewed-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Kirill A. Shuemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-07-09 22:42:01 -07:00
Baolin Wang
82241a83cd mm: fix the inaccurate memory statistics issue for users 
On some large machines with a high number of CPUs running a 64K pagesize
kernel, we found that the 'RES' field is always 0 displayed by the top
command for some processes, which will cause a lot of confusion for users.

    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND
 875525 root      20   0   12480      0      0 R   0.3   0.0   0:00.08 top
      1 root      20   0  172800      0      0 S   0.0   0.0   0:04.52 systemd

The main reason is that the batch size of the percpu counter is quite
large on these machines, caching a significant percpu value, since
converting mm's rss stats into percpu_counter by commit f1a7941243 ("mm:
convert mm's rss stats into percpu_counter").  Intuitively, the batch
number should be optimized, but on some paths, performance may take
precedence over statistical accuracy.  Therefore, introducing a new
interface to add the percpu statistical count and display it to users,
which can remove the confusion.  In addition, this change is not expected
to be on a performance-critical path, so the modification should be
acceptable.

In addition, the 'mm->rss_stat' is updated by using add_mm_counter() and
dec/inc_mm_counter(), which are all wrappers around
percpu_counter_add_batch().  In percpu_counter_add_batch(), there is
percpu batch caching to avoid 'fbc->lock' contention.  This patch changes
task_mem() and task_statm() to get the accurate mm counters under the
'fbc->lock', but this should not exacerbate kernel 'mm->rss_stat' lock
contention due to the percpu batch caching of the mm counters.  The
following test also confirm the theoretical analysis.

I run the stress-ng that stresses anon page faults in 32 threads on my 32
cores machine, while simultaneously running a script that starts 32
threads to busy-loop pread each stress-ng thread's /proc/pid/status
interface.  From the following data, I did not observe any obvious impact
of this patch on the stress-ng tests.

w/o patch:
stress-ng: info:  [6848]          4,399,219,085,152 CPU Cycles          67.327 B/sec
stress-ng: info:  [6848]          1,616,524,844,832 Instructions          24.740 B/sec (0.367 instr. per cycle)
stress-ng: info:  [6848]          39,529,792 Page Faults Total           0.605 M/sec
stress-ng: info:  [6848]          39,529,792 Page Faults Minor           0.605 M/sec

w/patch:
stress-ng: info:  [2485]          4,462,440,381,856 CPU Cycles          68.382 B/sec
stress-ng: info:  [2485]          1,615,101,503,296 Instructions          24.750 B/sec (0.362 instr. per cycle)
stress-ng: info:  [2485]          39,439,232 Page Faults Total           0.604 M/sec
stress-ng: info:  [2485]          39,439,232 Page Faults Minor           0.604 M/sec

On comparing a very simple app which just allocates & touches some
memory against v6.1 (which doesn't have f1a7941243) and latest Linus
tree (4c06e63b92) I can see that on latest Linus tree the values for
VmRSS, RssAnon and RssFile from /proc/self/status are all zeroes while
they do report values on v6.1 and a Linus tree with this patch.

Link: https://lkml.kernel.org/r/f4586b17f66f97c174f7fd1f8647374fdb53de1c.1749119050.git.baolin.wang@linux.alibaba.com
Fixes: f1a7941243 ("mm: convert mm's rss stats into percpu_counter")
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Aboorva Devarajan <aboorvad@linux.ibm.com>
Tested-by: Aboorva Devarajan <aboorvad@linux.ibm.com>
Tested-by Donet Tom <donettom@linux.ibm.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: SeongJae Park <sj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Hildenbrand <david@redhat.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-07-09 21:07:55 -07:00
Al Viro
b969f96148 fix proc_sys_compare() handling of in-lookup dentries 
There's one case where ->d_compare() can be called for an in-lookup
dentry; usually that's nothing special from ->d_compare() point of
view, but... proc_sys_compare() is weird.

The thing is, /proc/sys subdirectories can look differently for
different processes.  Up to and including having the same name
resolve to different dentries - all of them hashed.

The way it's done is ->d_compare() refusing to admit a match unless
this dentry is supposed to be visible to this caller.  The information
needed to discriminate between them is stored in inode; it is set
during proc_sys_lookup() and until it's done d_splice_alias() we really
can't tell who should that dentry be visible for.

Normally there's no negative dentries in /proc/sys; we can run into
a dying dentry in RCU dcache lookup, but those can be safely rejected.

However, ->d_compare() is also called for in-lookup dentries, before
they get positive - or hashed, for that matter.  In case of match
we will wait until dentry leaves in-lookup state and repeat ->d_compare()
afterwards.  In other words, the right behaviour is to treat the
name match as sufficient for in-lookup dentries; if dentry is not
for us, we'll see that when we recheck once proc_sys_lookup() is
done with it.

While we are at it, fix the misspelled READ_ONCE and WRITE_ONCE there.

Fixes: d9171b9345 ("parallel lookups machinery, part 4 (and last)")
Reported-by: NeilBrown <neilb@brown.name>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 2025-07-03 20:59:09 -04:00
David Hildenbrand
4a5e85f4eb fs/proc/task_mmu: fix PAGE_IS_PFNZERO detection for the huge zero folio 
is_zero_pfn() does not work for the huge zero folio. Fix it by using
is_huge_zero_pmd().

This can cause the PAGEMAP_SCAN ioctl against /proc/pid/pagemap to
present pages as PAGE_IS_PRESENT rather than as PAGE_IS_PFNZERO.

Found by code inspection.

Link: https://lkml.kernel.org/r/20250617143532.2375383-1-david@redhat.com
Fixes: 52526ca7fd ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs")
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 2025-06-25 15:55:03 -07:00
Al Viro
b5ba648a7d
proc_fd_getattr(): don't bother with S_ISDIR() check 
that thing is callable only as ->i_op->getattr() instance and only
for directory inodes (/proc/*/fd and /proc/*/task/*/fd)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/20250615003321.GC3011112@ZenIV
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
 2025-06-16 16:21:07 +02:00
Al Viro
ec169ef86b switch procfs from d_set_d_op() to d_splice_alias_ops() 
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 2025-06-10 22:13:52 -04:00
Al Viro
5943c611c4 procfs: kill ->proc_dops 
It has two possible values - one for "forced lookup" entries, another
for the normal ones.  We'd be better off with that as an explicit
flag anyway and in addition to that it opens some fun possibilities
with ->d_op and ->d_flags handling.

[moved PROC_ENTRY_FORCE_LOOKUP to include/linux/proc_fs.h, switched it
to an unused bit - there was a conflict]

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 2025-06-10 22:08:05 -04:00