Commit Graph

786 Commits

Author SHA1 Message Date
Linus Torvalds
2f43193b88 dma-mapping updates for Linux 7.3:
- swiotlb: added new configuration option for the default pool size
 (Jagadeesh Pagadala) and reduced overhead for high watermark tracking
 (chenhuguanshen)
 
 - minor code cleanups and improvements (Vova Sharaienko, Honglei Huang
 and Marek Szyprowski)
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQSrngzkoBtlA8uaaJ+Jp1EFxbsSRAUCaoxGQgAKCRCJp1EFxbsS
 RFPEAP0eo9usjFcvh0YKTPh6/mXgqxRuTNQZ7i+2lRGEczKcJQEA7mwkgwpiOaKn
 f++mMVOmsPvl2Y7r/5XqBWywwhyygA0=
 =X8pY
 -----END PGP SIGNATURE-----
mergetag object 04a19b35dc
 type commit
 tag dma-mapping-7.3-2026-08-24-2
 tagger Marek Szyprowski <m.szyprowski@samsung.com> 1787582472 +0200
 
 second dma-mapping update for Linux 7.3:
 
 - important dma-mapping update for confidential-computing, which adds
 proper tracking of the shared DMA state through direct, pool and swiotlb
 paths (Aneesh Kumar K.V)
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQSrngzkoBtlA8uaaJ+Jp1EFxbsSRAUCaoxYzgAKCRCJp1EFxbsS
 RM9bAP4mJuHHzj2DqsKV7QX19uhyzmsHIg+ecjBNRaOdUAgelQD9FsaG/fwrZnRT
 y89H0QUErqLsdmkDqV0zsXfaGzWY4gk=
 =dKjS
 -----END PGP SIGNATURE-----

Merge tags 'dma-mapping-7.3-2026-08-24' and 'dma-mapping-7.3-2026-08-24-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux

Pull dma-mapping updates from Marek Szyprowski:

 - swiotlb:
     - new configuration option for the default pool size
       (Jagadeesh Pagadala)
     - reduce overhead for high watermark tracking (chenhuguanshen)

 - minor code cleanups and improvements (Vova Sharaienko, Honglei Huang
   and Marek Szyprowski)

 - add proper tracking of the shared DMA state through direct, pool and
   swiotlb paths (Aneesh Kumar K.V)

   This is important for confidential-computing

* tag 'dma-mapping-7.3-2026-08-24' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
  dma/swiotlb: decouple high watermark tracking from CONFIG_DEBUG_FS
  MAINTAINERS: update tree for DMA MAPPING HELPERS
  dma/swiotlb: introduce Kconfig option for compile-time default pool size
  dma-direct: Improve readability of the dma_direct_map_sg() for P2PDMA case
  iommu/dma: simplify dma_iova_destroy() and drop the free_iova helper
  dma-coherent: use KiB in DMA allocation logs
  dma-coherent: fix spacing coding style issue

* tag 'dma-mapping-7.3-2026-08-24-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: (23 commits)
  swiotlb: remove unused SWIOTLB_FORCE flag
  dma: swiotlb: handle set_memory_decrypted() failures
  dma: swiotlb: free dynamic pools from process context
  dma-direct: rename ret to cpu_addr in alloc helpers
  dma-direct: select DMA address encoding from __DMA_ATTR_ALLOC_CC_SHARED
  dma-direct: set decrypted flag for remapped DMA allocations
  dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHARED
  dma-direct: Move dma_direct_map_phys() to dma/direct.c
  dma-direct: pass attrs to dma_capable() for DMA_ATTR_CC_SHARED checks
  dma-mapping: make dma_pgprot() honor __DMA_ATTR_ALLOC_CC_SHARED
  dma: swiotlb: track pool encryption state and honor DMA_ATTR_CC_SHARED
  dma: swiotlb: pass mapping attributes by reference
  dma-pool: track decrypted atomic pools and select them via attrs
  dma-direct: use __DMA_ATTR_ALLOC_CC_SHARED in alloc/free paths
  dma-mapping: Add internal shared allocation attribute
  coco: arm64: s390: powerpc: Mark secure guests with CC_ATTR_GUEST_MEM_ENCRYPT
  dma-direct: swiotlb: handle swiotlb alloc/free outside __dma_direct_alloc_pages
  s390: Expose protected virtualization through cc_platform_has()
  swiotlb: Preserve allocation virtual address for dynamic pools
  dma: free atomic pool pages by physical address
  ...
2026-08-24 11:35:46 -07:00
Linus Torvalds
66ec24c5d7 s390 updates for 7.3 merge window
- Add a cpuidle driver with polling and enabled wait states using the
   existing CPU idle infrastructure and idle governor to improve latency
   for frequent sleep/wakeup cycles. Remove the obsolete tick delay
   heuristic and generic arch_needs_cpu() hook. Add the corresponding
   driver entry to MAINTAINERS
 
 - Add kCFI support using the generic support provided by Clang
 
 - Enable Clang CONTEXT_ANALYSIS for various architecture code and for
   char, PCI, CIO and virtio drivers. Add required lock annotations,
   exclude unsupported mm helpers and remove conditional PCI locking
 
 - Fix secure storage access exception handling and reintroduce
   DCACHE_WORD_ACCESS previously removed as a workaround
 
 - Fix cpum_cf perf crashes when CPUs are brought online while per-task
   events are active. Allocate and remove per-CPU counter data from CPU
   hotplug callbacks
 
 - Fix a deadlock when an s390dbf debug area is unregistered while one
   of its debugfs files is being written to
 
 - Fix MVIY_PERCPU() with binutils older than 2.39, where an assembler
   macro silently omitted an instruction needed to repair interrupted
   operations after CPU migration
 
 - Remove/replace cond_resched() calls which are no-ops with the supported
   s390 preemption models
 
 - Fix AP queue depth and maximum message length decoding according to
   the architecture. Current hardware is not affected, but future hardware
   could report values which were handled incorrectly
 
 - Reflect the configured CPU state in cpu_enabled_mask so deconfigured
   CPUs are not presented as available for onlining
 
 - Restore the vDSO GNU_EH_FRAME program header which was lost when the
   build switched to direct linker invocation, and mark it read-only
 
 - Add SCLP action qualifiers used by Spyre for card initialization,
   recoverable error and telemetry reporting
 
 - Move KMSAN interrupt flag helpers out of line to fix
   -Wstatic-in-inline build warnings
 
 - Use level-specific page table entry accessors for hugetlb entries and
   ptep_get() when accessing crashed kernel memory in kdump
 
 - Make forced AP bus rescans killable so that a user process blocked
   behind an ongoing scan can still be terminated with SIGKILL
 
 - Rework pkey ioctl error paths to remove duplicated cleanup code and
   avoid freeing error pointers
 
 - Allow the protected guest SWIOTLB buffer to be allocated outside the
   first 2GB. Also enable dynamic SWIOTLB growth and the coherent atomic
   pool fallback to improve I/O behavior when the initial pool is exhausted
 
 - Add program check statistics and spinlock contention tracepoints.
   Increase the lockdep chain capacity to keep lockdep enabled for complex
   code paths such as btrfs
 
 - Simplify IPL, trap and syscall code and remove the obsolete unistd_32.h
   generation entry
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCgAdFiEE3QHqV+H2a8xAv27vjYWKoQLXFBgFAmqLHuoACgkQjYWKoQLX
 FBhf2Qf+JlV+jQM1Lvn/Dj16vuQ77a4aP5C/OnLGMaTrrzbX420qU04yvC96v2Xu
 ux01aDU9VakonE74IT0NmrNo1VDUk8nSvIWUTB6GH7KvK76VEZN5Kkyn8TmeRmE0
 bZ0Fg7MgnhwdYijFDiX9w4rLyirwxs7vkScdJdJd0iKEdoZHXojGSjPDvmSpXght
 FgCszt+YOqu9MMf9B5oGAl+P40mgPTlm6M+ygoe2dX7qPQBUHLbDPTgZiWnKdXi2
 LPx0QPEha921ePDWrWz2HEqNetMfwGl12iertXddf1uzuK6LLObi0M5QrGw/ZbOy
 UJFM+AjFekTQyZPSunD4NWyCjglqrA==
 =XF7Y
 -----END PGP SIGNATURE-----

Merge tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add a cpuidle driver with polling and enabled wait states using the
   existing CPU idle infrastructure and idle governor to improve latency
   for frequent sleep/wakeup cycles. Remove the obsolete tick delay
   heuristic and generic arch_needs_cpu() hook. Add the corresponding
   driver entry to MAINTAINERS

 - Add kCFI support using the generic support provided by Clang

 - Enable Clang CONTEXT_ANALYSIS for various architecture code and for
   char, PCI, CIO and virtio drivers. Add required lock annotations,
   exclude unsupported mm helpers and remove conditional PCI locking

 - Fix secure storage access exception handling and reintroduce
   DCACHE_WORD_ACCESS previously removed as a workaround

 - Fix cpum_cf perf crashes when CPUs are brought online while per-task
   events are active. Allocate and remove per-CPU counter data from CPU
   hotplug callbacks

 - Fix a deadlock when an s390dbf debug area is unregistered while one
   of its debugfs files is being written to

 - Fix MVIY_PERCPU() with binutils older than 2.39, where an assembler
   macro silently omitted an instruction needed to repair interrupted
   operations after CPU migration

 - Remove/replace cond_resched() calls which are no-ops with the
   supported s390 preemption models

 - Fix AP queue depth and maximum message length decoding according to
   the architecture. Current hardware is not affected, but future
   hardware could report values which were handled incorrectly

 - Reflect the configured CPU state in cpu_enabled_mask so deconfigured
   CPUs are not presented as available for onlining

 - Restore the vDSO GNU_EH_FRAME program header which was lost when the
   build switched to direct linker invocation, and mark it read-only

 - Add SCLP action qualifiers used by Spyre for card initialization,
   recoverable error and telemetry reporting

 - Move KMSAN interrupt flag helpers out of line to fix
   -Wstatic-in-inline build warnings

 - Use level-specific page table entry accessors for hugetlb entries and
   ptep_get() when accessing crashed kernel memory in kdump

 - Make forced AP bus rescans killable so that a user process blocked
   behind an ongoing scan can still be terminated with SIGKILL

 - Rework pkey ioctl error paths to remove duplicated cleanup code and
   avoid freeing error pointers

 - Allow the protected guest SWIOTLB buffer to be allocated outside the
   first 2GB. Also enable dynamic SWIOTLB growth and the coherent atomic
   pool fallback to improve I/O behavior when the initial pool is
   exhausted

 - Add program check statistics and spinlock contention tracepoints.
   Increase the lockdep chain capacity to keep lockdep enabled for
   complex code paths such as btrfs

 - Simplify IPL, trap and syscall code and remove the obsolete
   unistd_32.h generation entry

* tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (59 commits)
  s390/percpu: Fix MVIY_PERCPU() with older binutils
  s390/debug: Fix deadlock during unregister
  s390/cpum_cf: Handle CPU hotplug via prepare/dead callbacks
  s390: Enable CONTEXT_ANALYSIS for various directories
  s390/mm: Add __context_unsafe() attribute to gmap helper functions
  s390/mm: Add __context_unsafe() attribute to do_secure_storage_access()
  s390/sysinfo: Add context analysis attributes
  s390/irqflags: Add out-of-line definitions of arch_local_irq_*() for KMSAN
  s390/virtio: Enable CONTEXT_ANALYSIS
  s390/cio: Enable CONTEXT_ANALYSIS
  s390/vfio_ccw: Add __must_hold() attribute to vfio_ccw_sch_quiesce()
  s390/pci: Enable CONTEXT_ANALYSIS
  s390/pci: Rework __zpci_event_availability() to remove conditional locking
  s390/pci: Rework __zpci_event_error() to remove conditional locking
  s390/char: Enable CONTEXT_ANALYSIS
  s390/con3215: Add __must_hold() attribute to raw3215_make_room()
  s390/ap: Fix MAPML computation
  s390/cio: Remove cond_resched() calls
  s390: Remove cond_resched() calls
  KVM: s390: Remove cond_resched() calls
  ...
2026-08-23 10:26:44 -07:00
Linus Torvalds
ed3b875bea mm.git review status for mm-hotfixes-stable..mm-stable
Everything:
 
 Total patches:       501
 Reviews/patch:       1.66
 Reviewed rate:       70%
 
 Excluding DAMON:
 
 Total patches:       356
 Reviews/patch:       2.26
 Reviewed rate:       90%
 
 Excluding DAMON and selftests:
 
 Total patches:       329
 Reviews/patch:       2.31
 Reviewed rate:       92%
 
 Excluding DAMON, selftests and maple_tree:
 
 Total patches:       328
 Reviews/patch:       2.31
 Reviewed rate:       92%
 
 Summary of patch series in this merge:
 
 - The 2 patch series "mm: drop "sub" prefix from various places" from
   Dev Jain implements some page->folio conversion and a naming cleanup.
 
 - The 2 patch series "mm/kasan: remove redundant initialization for
   kasan_flag_write_only" from Igor Putko provides some KASAN cleanup work.
 
 - The 2 patch series "mm/filemap: reduce unnecessary xarray lookups"
   from Chi Zhiling provides a small speedup in the pagecaache read code.
 
 - The 4 patch series "mm/percpu: Fix possible NOFS/NOIO reclaim
   recursion" from Kaitao Cheng improves a few things in the vmalloc code -
   mainly the avoidance of GFP_KERNEL allocations when the caller asked for
   GFP_NOFS or GFP_NOIO.
 
 - The 3 patch series "mm/kmemleak: avoid soft lockup when scanning task
   stacks" from Breno Leitao avoids a soft lockup watchdog trigger from the
   kmemleak scanning code in extreme situations.
 
 - The 6 patch series "mm/page_owner: misc cleanups" from Ye Liu is a
   collection of unrelated cleanups to the page_owner code.  For some
   reason lots of people have been working on the page_owner code this
   cycle.
 
 - The 4 patch series "mm: convert to walk_page_range_vma() to eliminate
   find_vma()" from Kefeng Wang simplifies and accelerates the page walking
   library function.
 
 - The 3 patch series "mm/migrate: preparatory cleanups for batch copy
   and offload" from Shivank Garg implements cleanups in the migration
   code.
 
 - The 4 patch series "mm/page_owner: add per-fd filter infrastructure
   for print_mode and NUMA filtering" from Zhen Ni provides per-fd
   filtering to page_owner in order to reduce the sometimes vast amount of
   output it can produce.
 
 - The 19 patch series "mm: Refactor bootmem gigantic hugepage
   allocation" from Muchun Song is a "set of fixes and preparatory cleanups
   around bootmem HugeTLB handling, sparse initialization ordering, and
   related vmemmap setup".
 
 - The 4 patch series "mm/zsmalloc: reduce lock contention in zs_free()"
   from Wenchao Hao reduces lock contention in zs_free(), which dominates
   the unmap path under memory pressure on Android (LMK kills) and on x86
   servers running zswap-heavy workloads.  Up to 1.83x improvement in
   microbenchmarking.
 
 - The 2 patch series "move alloc_tag.c file under mm/" from Suren
   Baghdasaryan does that.
 
 - The 6 patch series "samples/damon: handle damon_{start,stop}()
   failures" from SJ Park fixes improper handling of damon_start(),
   damon_stop(), and damon_call() failures across DAMON sample modules to
   prevent potential memory leaks, operation disruptions and use-after-free
   bugs.
 
 - The 11 patch series "mm/damon/sysfs: kobject_del() directories that
   users can create/remove" from SJ Park resolves an issue where delayed
   sysfs directory removal under CONFIG_DEBUG_KOBJECT_RELEASE causes
   creation failures due to duplicate directory names by adding missing
   kobject_del() calls before creating new directories.
 
 - The 3 patch series "mm: cleanup clear_not_present_full_ptes()" from
   David Hildenbrand cleans up the core pte handling code.
 
 - The 3 patch series "selftests/damon: misc fixes for test bugs" from
   Kunwu Chan fixes several bugs in the DAMON selftests.
 
 - The 2 patch series "selftests/damon: fix memcg_path staging handling"
   from Cheng Nie fixes a bug in _damon_sysfs.py for damos_filter
   memcg_path setup, and adds a test case for it in sysfs.py.
 
 - The 2 patch series "selftests/damon: test kdamond refresh_ms" from
   Ruslan Valiyev introduces selftest coverage for DAMON's refresh_ms sysfs
   feature by updating the test control module and verifying that scheme
   stats update automatically without manual intervention.
 
 - The 5 patch series "mm/damon: five misc fixups" from Akinobu Mita
   contains miscellaneous DAMON fixups.
 
 - The 2 patch series "mm/damon/core: detect internal variation above
   max_nr_regions/2" from Jiayuan Chen fixes DAMON's region splitting
   behavior when region counts exceed half the maximum budget by
   dynamically scaling down the split fraction as the limit approaches,
   preventing large regions from staying un-split, and adds corresponding
   KUnit test coverage.
 
 - The 6 patch series "mm: preparatory patches for PMD level swap
   entries" from Usama Arif refactors and cleans up PMD softleaf helpers,
   call sites, and architecture flags to lay the groundwork for a follow-up
   series that introduces PMD page table swap entries.
 
 - The 11 patch series "mm/damon: update, optimize, and clean up doc,
   tests, and code" from SJ Park updates DAMON design and ABI
   documentation, expands unit and selftest coverage, optimizes
   damon_commit_target_regions(), and cleans up recently added sysfs
   interface code for better readability.
 
 - The 2 patch series "mm/vmpressure: reduce CPU, memory and code
   overhead on cgroup v2" from Usama Arif optimizes vmpressure() by
   skipping unnecessary work on cgroup v2 for userspace event notifications
   and refactors v1-only eventfd handling into mm/memcontrol-v1.c to reduce
   memory overhead and code complexity.
 
 - The 10 patch series "selftests/mm: refactor pkey helpers and fix mmap
   error handling" from Hongfu Li refactors pkeys shared tracing and
   assertion helpers into a common file, unifies protection key selftests
   to use consistent diagnostic logging and assertions, and enforces
   standardized MAP_FAILED return checks for mmap() calls across the tests.
 
 - The 18 patch series "mm/damon: optimize out nr_accesses_bp" from SJ
   Park replaces the error-prone, continuously updated nr_accesses_bp field
   in damon_region with an on-demand moving sum function
   (damon_nr_accesses_mvsum()), reducing structure memory overhead and
   avoiding state corruption bugs.
 
 - The 6 patch series "Open HugeTLB allocation routine for more generic
   use" from Ackerley Tng decouples HugeTLB folio allocation from VMA
   dependencies by introducing hugetlb_alloc_folio(), enabling subsystems
   like guest_memfd to allocate HugeTLB folios without standard VMA
   reservations or pseudo-VMAs.
 
 - The 3 patch series "mm/damon: provide pseudo moving sum probe_hits"
   from SJ Park integrates DAMON's probe_hits attribute counter into the
   pseudo moving sum infrastructure, enabling real-time, online monitoring
   without waiting for full aggregation intervals.
 
 - The 18 patch series "mm: Some cleanups for page allocator APIs" from
   Brendan Jackman simplifies and refactors the page allocator entry points
   and flags by unifying allocation paths, adding internal alloc_flags
   arguments, and eliminating redundant __ prefixed alloc_pages variants.
 
 - The 5 patch series "Fix incorrect access of hugetlb pte entries" from
   Dev Jain enforces the consistent use of huge_ptep_get() instead of
   ptep_get() for HugeTLB entries and fixes an unaligned address issue in
   arm64's huge_ptep_get() implementation.
 
 - The 8 patch series "mm/damon: validate all parameters in the core"
   from SJ Park consolidates parameter validation into the DAMON core
   specifically within damon_start() and damon_commit_ctx() to centralize
   error checking, eliminate caller-side redundant checks and to improve
   maintenance efficiency.
 
 - The 3 patch series "tools/mm/page_owner_sort: fix filtering and
   cleanup issues" from Yichong Chen renames is_need() to filter_record()
   for clearer return semantics, fixes per-record allocation memory leaks
   and bounds output copies in search_pattern() to address an existing
   buffer issue.
 
 - The 4 patch series "memcg: bail out reclaim when memcg is dying" from
   Jiayuan Chen mitigates a system-wide stall which occurs when a cgroup is
   removed while one of its memory control files is doing synchronous
   reclaim.
 
 - The 5 patch series "mm/memory-failure: add panic option for
   unrecoverable pages" from Breno Leitao introduces an opt-in
   vm.panic_on_unrecoverable_memory_failure sysctl that immediately panics
   the kernel on unrecoverable memory errors in kernel-owned pages to
   preserve error context and prevent delayed, silent data corruption.
 
 - The 11 patch series "mm/damon: refactor damon_{start,stop,commit}()
   for simple error handling" from SJ Park refactors the DAMON core API
   functions to guarantee that all contexts are fully stopped when
   damon_start(), damon_stop(), or damon_commit() fail, eliminating the
   need for complex and error-prone caller-side cleanup code.
 
 - The 5 patch series "Keep tail page private zero at free and folio
   split" from Zi Yan adds checks to ensure tail_page->private is zero when
   freeing compound or high-order pages and when promoting tail pages
   during large folio splits.  By validating these fields at free and split
   time, it allows the removal of redundant private field clearing inside
   prep_compound_tail().
 
 - The 4 patch series "mm: drop redundant lru_add_drain in anon folio
   reuse paths" from Barry Song eliminates redundant lru_add_drain() calls
   in wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock
   contention and system overhead.
 
   By validating folio refcounts against the LRU cache before draining
   and removing unnecessary drains in the swap path, it achieves up to a
   30.5% reduction in drain calls during heavy swap workloads.
 
 - The 3 patch series "mm: clean up folio LRU and swap declarations" from
   Jianyue Wu reorganizes folio LRU and swap code by relocating
   page-cluster state to mm/swap_state.c, renaming mm/swap.c to mm/folio.c,
   and moving MM-internal reclaim declarations into mm/internal.h.
 
 - The 15 patch series "userfaultfd: working set tracking for VM guest
   memory" from Kiryl Shutsemau adds userfaultfd support for tracking the
   working set of VM guest memory, so a VMM can identify hot pages and
   reclaim cold ones to tiered or remote storage.
 
 - The 10 patch series "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part
   2)" from David Hildenbrand removes the remaining pieces of
   CONFIG_HAVE_BOOTMEM_INFO_NODE, performing some smaller cleanups around
   freeing of reserved vmemmap pages on the way.
 
 - The 7 patch series "mm/damon: update probe hits for runtime parameter
   commits" from SJ Park ensures that DAMON's probe_hits attribute counter
   is properly updated when monitoring intervals are changed at runtime,
   matching the behavior of nr_accesses.  To achieve this, it refactors and
   renames existing helper functions for shared use, applies the updates to
   probe_hits, and handles edge cases in damon_probe_hits_mvsum() to
   maintain measurement accuracy.
 
 - The 3 patch series "KSM: performance optimizations for rmap_walk_ksm"
   from xu xin resolves a severe KSM reverse-mapping performance bottleneck
   where thousands of split VMAs sharing a single anon_vma cause extended
   lock contention.  By adding an interval-filtering check during the rmap
   walk, it reduces worst-case anon_vma lock hold times from over 500ms
   down to under 2ms, preventing application freezes and latency spikes
   under memory pressure.
 
 - The 3 patch series "mm: split a couple of headers from internal.h"
   from Mike Rapoport splits declarations related to mm_init, memblock,
   vmalloc and sparse into new headers.
 
 - The 2 patch series "KSM: use linear_page_index in collect_procs_ksm()"
   from xu xin applies the interval tree optimization from rmap_walk_ksm()
   to collect_procs_ksm() to avoid iterating over non-matching VMAs during
   KSM memory error handling.  It hoists loop-invariant address
   initialization and restricts the anon_vma_interval_tree_foreach walk to
   a targeted page offset range, reducing redundant checks and improving
   lookup efficiency.
 
 - The 3 patch series "selftests/mm: avoid false failures in hugetlb and
   KSM tests" from Sayali Patil fixes issues in the hugetlb and KSM MM
   selftest categories that can report failures when the prerequisites for
   the tests are not satisfied.
 
 - The 19 patch series "mm/damon: introduce data attributes only
   monitoring" from SJ Park introduces attribute-weighted region management
   in DAMON, allowing users to prioritize specific data attributes (such as
   page sizes or cgroups) over or instead of access monitoring.
 
   By assigning weights to attribute probes, DAMON can completely disable
   access tracking and adjust monitoring regions based on weighted
   probe-hit counters to optimize monitoring quality for attribute-focused
   workloads.
 
 - The 8 patch series "mm/hmm: Add mmap lock-drop support for
   userfaultfd-backed mappings" from Stanislav Kinsburskii extends
   hmm_range_fault() to support userfaultfd-backed regions by allowing the
   mmap lock to be dropped during fault handling via a new
   hmm_range_fault_locked() helper.
 
   By accepting a locked pointer and signaling retry status when lock
   release occurs, it enables page fault resolution in userfaultfd regions
   while preserving backward compatibility for existing callers.
 
 - The 33 patch series "mm: make VMA page offset handling more
   consistent" from Lorenzo Stoakes cleans up and standardizes how
   vma->vm_pgoff is accessed and manipulated across file-backed and
   anonymous mappings in the kernel.
 
   It introduces dedicated helper functions such as vma_start_pgoff(),
   vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while renaming
   rmap interval tree helpers to better reflect their functionality.
 
   These changes establish a cleaner foundation for future work that will
   unify virtual page offset indexing for all anonymous and CoW'd folios.
 
 - The 3 patch series "mm: handle device-private PMDs in walk callbacks"
   from Usama Arif addresses kernel panics and state corruption caused by
   MM walk callbacks reaching non-present device-private PMD swap entries
   created during HMM migrations.
 
   It ensures that functions which acquire pmd_trans_huge_lock() properly
   recognize device-private PMDs instead of assuming a present THP or a
   standard migration entry.
 
 - The 5 patch series "mm/rmap: Refactor try_to_unmap_one" from Dev Jain
   refactors try_to_unmap_one by modularizing Hugetlb, anonymous-lazyfree,
   and anonymous-swapbacked logic into dedicated functions, laying the
   structural groundwork for batched anonymous large folio unmapping.
 
 - The 4 patch series "Docs/ABI/damon: sysfs ABI document fixes and
   additions" from Song Hu fixes typos and fills in missing entries in the
   DAMON sysfs ABI document.
 
 - The 10 patch series "dax/kmem: atomic whole-device hotplug via sysfs"
   from Gregory Price introduces an atomic sysfs state attribute and
   supporting DAX/MM infrastructure to prevent userland races when
   offlining and removing entire memory regions.
 
   By adding an unplugged state alongside standard online modes, it
   enables whole-device atomic hotplug control while preserving backward
   compatibility.
 
 - The 13 patch series "mm: convert more vm_flags_t users to vma_flags_t"
   from Lorenzo Stoakes continues transitioning the kernel from the
   deprecated vm_flags_t type to vma_flags_t across core memory management
   infrastructure.
 
   It replaces legacy type usage in core functions such as do_mmap(),
   unmapped area allocation, mm->def_vma_flags, and VMA operations like
   mlock, mprotect, and mremap.
 
 - The 2 patch series "Two small patches to clean up mm/mm_slot.h" from
   xu xin refactors mm_slot.h by introducing mm_slot_remove() to unify
   duplicate slot deletion sequences in khugepaged and KSM.  It also adds
   code documentation explaining why mm_slot_lookup and mm_slot_insert must
   remain as preprocessor macros rather than static inline functions.
 
 - The 10 patch series "mm/damon/core: hide core-private struct fields"
   from SJ Park cleans up DAMON core structures by consistently marking
   internal-only fields with private: comment tags to prevent improper
   direct access from outer layers.
 
   It enforces encapsulation across core structures including
   damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to
   interact through approved access APIs instead of exposing raw struct
   members.
 
 - The 6 patch series "mm/damon: unurgent fixes for infinite loop, NULL
   de-ref and races" from SJ Park addresses potential infinite loops, NULL
   dereferences, and race conditions identified in DAMON.
 
   It fixes an infinite loop triggered by extreme user configurations, a
   NULL pointer dereference within unit tests and minor monitoring
   accuracy degradation caused by subtle runtime races.
 
 - The 2 patch series "mm/page_alloc: fixes for free_pages_nolock() on
   RT/UP" from Brendan Jackman fixes an NMI safety flaw in
   __free_frozen_pages() where freeing pages on non-SMP or PREEMPT_RT
   kernels can bypass can_spin_trylock() checks via non-PCP or isolated
   migration paths.
 
   It also resolves potential kernel crashes and privilege escalation
   risks triggered when BPF tracing runs in NMI context alongside memory
   hotplug or large allocation frees.
 
 - The 4 patch series "mm/page_alloc: couple of followups for recent
   cleanups" from Brendan Jackman cleans up and updates page allocator
   nomenclature, documentation, and debug assertions.
 
   It aligns internal FPI_ flags with the public "nolock" naming
   convention, removes outdated internal implementation details from
   high-level page allocator comments, and eliminates obsolete VM_BUG_ON()
   assertions in allocation paths.
 
 - The 3 patch series "mm/mseal: further cleanups" from Lorenzo Stoakes
   refactors and simplifies the mseal implementation by clarifying API
   boundaries and removing unnecessary code complexity.
 
   It replaces generic do_mseal() usage outside the syscall with a
   dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO, eliminates
   mm_struct parameters to enforce that sealing applies only to
   current->mm, and streamlines overall logic and comments with no
   functional changes intended.
 
 - The 4 patch series "mm/vmscan: fix swappiness=max and clean up
   per-node proactive reclaim" from Ridong Chen resolves reclaim behavior
   bugs and cleans up function parameters across memory reclaim paths.
 
   It fixes swappiness=max in both standard reclaim and MGLRU so
   unswappable anonymous memory no longer falls back to evicting page
   cache, ensures reclaim_store() returns accurate error codes instead of
   collapsing all failures into -EAGAIN, and removes the obsolete gfp_mask
   parameter from __node_reclaim().
 
 - The 6 patch series "mm: mincore: misc cleanups" from Kefeng Wang
   cleans up and simplifies the mincore code.  Most importantly, it removes
   the historical special behavior that always reports VM_PFNMAP pages as
   non-resident.
 
 - The 2 patch series "mm/huge_memory: drop dead split helper variants"
   from Kiryl Shutsemau implements two trivial cleanups in the folio split
   API.
 
 - The 7 patch series "mm/damon: fix uninitialized DAMOS field and kunit
   exec expectation bugs" from SJ Park resolves minor operational and
   testing bugs in DAMON identified by Sashiko.  It initializes the
   damos->last_applied field to prevent occasional efficiency degradation
   and fixes invalid memory accesses in DAMON KUnit tests during test
   failure handling.
 
 - The 3 patch series "cleanup for stable_page_flags()" from Jinjiang Tu
   cleans up and refactors stable_page_flags() used by /proc/kpageflags
   without altering functionality.
 
   It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag
   bits, converts folio-specific flag checks to standard folio_test_*()
   helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling.
 
 - The 3 patch series "Batch unmap of uffd-wp file folios" from Dev Jain
   extends batched folio unmapping support to file folios within
   userfaultfd write-protect (uffd-wp) VMAs by adding batching capabilities
   to pte_install_uffd_wp_if_needed().
 
   This removes special-case restrictions on uffd-wp VMAs in
   try_to_unmap_one(), significantly simplifying the function's control
   flow and complexity.
 
 - The 3 patch series "mm/early_ioremap: clarify and clean up
   early_ioremap_reset()" from Sang-Heon Jeon clarifies and cleans up the
   architecture-specific usage of __late_set_fixmap() and
   __late_clear_fixmap() after early_ioremap_reset().
 
   It adds explicit documentation regarding when early_ioremap_reset()
   must be called and removes redundant macro definitions and reset calls
   in the RISC-V and ARM64 architectures.
 
 - The 4 patch series "mm: fix reclaim storms in defrag_mode" from
   Johannes Weiner addresses severe performance regressions, swap storms,
   and spurious OOMs caused by vm.defrag_mode=1 under high memory pressure
   in Meta production.
 
   It updates the page allocator slowpath so non-movable allocation
   requests actively trigger direct reclaim and direct compaction at
   pageblock_order scale, allowing them to claim whole pageblocks rather
   than spinning unproductively.
 
 - The 2 patch series "zram: lockmap tweaks" from Sebastian Siewior
   optimizes and fixes lockdep tracking for zram devices by consolidating
   per-entry lockmaps and isolating lock classes across multiple instances.
 
   It reduces memory overhead by replacing per-entry lockdep_map instances
   with a single map per struct zram, and assigns a dynamic lock_class_key
   to each instance to prevent false deadlock reports when different zram
   devices are backed by distinct filesystems.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaoUJbQAKCRDdBJ7gKXxA
 jqrzAP9WoPU0hiK4qS/kSjhtoZxhjpS5eLSUCy/utKuEvZbfGgEAu1zA+LH+X9Tm
 THK5ex4iUZxiFbXpWfLMxE/Q9PmQYQ8=
 =QTyb
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - "mm: drop "sub" prefix from various places" (Dev Jain)

   page->folio conversion and a naming cleanup

 - "mm/kasan: remove redundant initialization for kasan_flag_write_only"
   (Igor Putko)

   KASAN cleanup work

 - "mm/filemap: reduce unnecessary xarray lookups" (Chi Zhiling)

   Small speedup in the pagecaache read code

 - "mm/percpu: Fix possible NOFS/NOIO reclaim recursion" (Kaitao Cheng)

   Improve the vmalloc code - mainly the avoidance of GFP_KERNEL
   allocations when the caller asked for GFP_NOFS or GFP_NOIO

 - "mm/kmemleak: avoid soft lockup when scanning task stacks" (Breno
   Leitao)

   Avoid a soft lockup watchdog trigger from the kmemleak scanning code
   in extreme situations

 - "mm/page_owner: misc cleanups" (Ye Liu)

   Cleanups to the page_owner code. For some reason lots of people have
   been working on the page_owner code this cycle.

 - "mm: convert to walk_page_range_vma() to eliminate find_vma()"
   (Kefeng Wang)

   Simplify and accelerate the page walking library function

 - "mm/migrate: preparatory cleanups for batch copy and offload"
   (Shivank Garg)

   Cleanups in the migration code

 - "mm/page_owner: add per-fd filter infrastructure for print_mode and
   NUMA filtering" (Zhen Ni)

   Per-fd filtering to page_owner in order to reduce the sometimes vast
   amount of output it can produce

 - "mm: Refactor bootmem gigantic hugepage allocation" (Muchun Song)

   Fixes and preparatory cleanups around bootmem HugeTLB handling,
   sparse initialization ordering, and related vmemmap setup

 - "mm/zsmalloc: reduce lock contention in zs_free()" (Wenchao Hao)

   Reduce lock contention in zs_free(), which dominates the unmap path
   under memory pressure on Android (LMK kills) and on x86 servers
   running zswap-heavy workloads.

   Up to 1.83x improvement in microbenchmarking.

 - "move alloc_tag.c file under mm/" (Suren Baghdasaryan)

 - "samples/damon: handle damon_{start,stop}() failures" (SJ Park)

   Fix improper handling of damon_start(), damon_stop(), and
   damon_call() failures across DAMON sample modules to prevent
   potential memory leaks, operation disruptions and use-after-free
   bugs

 - "mm/damon/sysfs: kobject_del() directories that users can
   create/remove" (SJ Park)

   Fix delayed sysfs directory removal under DEBUG_KOBJECT_RELEASE
   causeing creation failures due to duplicate directory names by adding
   missing kobject_del() calls before creating new directories

 - "mm: cleanup clear_not_present_full_ptes()" (David Hildenbrand)

   Clean up the core pte handling code

 - "selftests/damon: misc fixes for test bugs" (Kunwu Chan)

   Fix several bugs in the DAMON selftests

 - "selftests/damon: fix memcg_path staging handling" (Cheng Nie)

   Fix a bug in _damon_sysfs.py for damos_filter memcg_path setup, and
   add a test case for it in sysfs.py.

 - "selftests/damon: test kdamond refresh_ms" (Ruslan Valiyev)

   Selftest coverage for DAMON's refresh_ms sysfs feature by updating
   the test control module and verifying that scheme stats update
   automatically without manual intervention

 - "mm/damon: five misc fixups" (Akinobu Mita)

   Miscellaneous DAMON fixups.

 - "mm/damon/core: detect internal variation above max_nr_regions/2"
   (Jiayuan Chen)

   Fix DAMON's region splitting behavior when region counts exceed half
   the maximum budget by dynamically scaling down the split fraction as
   the limit approaches, preventing large regions from staying un-split,
   and add corresponding KUnit test coverage

 - "mm: preparatory patches for PMD level swap entries" (Usama Arif)

   Refactor and clean up PMD softleaf helpers, call sites, and
   architecture flags to lay the groundwork for a follow-up series that
   introduces PMD page table swap entries

 - "mm/damon: update, optimize, and clean up doc, tests, and code" (SJ
   Park)

   Update DAMON design and ABI documentation, expands unit and selftest
   coverage, optimize damon_commit_target_regions(), and clean up
   recently added sysfs interface code for better readability

 - "mm/vmpressure: reduce CPU, memory and code overhead on cgroup v2"
   (Usama Arif)

   Optimize vmpressure() by skipping unnecessary work on cgroup v2 for
   userspace event notifications and refactor v1-only eventfd handling
   into mm/memcontrol-v1.c to reduce memory overhead and code complexity

 - "selftests/mm: refactor pkey helpers and fix mmap error handling"
   (Hongfu Li)

   Refactor pkeys shared tracing and assertion helpers into a common
   file, unify protection key selftests to use consistent diagnostic
   logging and assertions, and enforce standardized MAP_FAILED return
   checks for mmap() calls across the tests

 - "mm/damon: optimize out nr_accesses_bp" (SJ Park)

   Replace the error-prone, continuously updated nr_accesses_bp field in
   damon_region with an on-demand moving sum function, reducing
   structure memory overhead and avoiding state corruption bugs

 - "Open HugeTLB allocation routine for more generic use" (Ackerley Tng)

   Decouple HugeTLB folio allocation from VMA dependencies by
   introducing hugetlb_alloc_folio(), enabling subsystems like
   guest_memfd to allocate HugeTLB folios without standard VMA
   reservations or pseudo-VMAs

 - "mm/damon: provide pseudo moving sum probe_hits" (SJ Park)

   Integrate DAMON's probe_hits attribute counter into the pseudo moving
   sum infrastructure, enabling real-time, online monitoring without
   waiting for full aggregation intervals

 - "mm: Some cleanups for page allocator APIs" (Brendan Jackman)

   Simplify and refactor the page allocator entry points and flags by
   unifying allocation paths, adding internal alloc_flags arguments, and
   eliminating redundant __ prefixed alloc_pages variants.

 - "Fix incorrect access of hugetlb pte entries" (Dev Jain)

   Enforce the consistent use of huge_ptep_get() instead of ptep_get()
   for HugeTLB entries and fixes an unaligned address issue in arm64's
   huge_ptep_get() implementation

 - "mm/damon: validate all parameters in the core" (SJ Park)

   Consolidate parameter validation into the DAMON core specifically
   within damon_start() and damon_commit_ctx() to centralize error
   checking, eliminate caller-side redundant checks and to improve
   maintenance efficiency

 - "tools/mm/page_owner_sort: fix filtering and cleanup issues" (Yichong
   Chen)

   Rename is_need() to filter_record() for clearer return semantics, fix
   per-record allocation memory leaks and bound output copies in
   search_pattern() to address an existing buffer issue

 - "memcg: bail out reclaim when memcg is dying" (Jiayuan Chen)

   Mitigate a system-wide stall which occurs when a cgroup is removed
   while one of its memory control files is doing synchronous reclaim

 - "mm/memory-failure: add panic option for unrecoverable pages" (Breno
   Leitao)

   Introduce an opt-in vm.panic_on_unrecoverable_memory_failure sysctl
   that immediately panics the kernel on unrecoverable memory errors in
   kernel-owned pages to preserve error context and prevent delayed,
   silent data corruption

 - "mm/damon: refactor damon_{start,stop,commit}() for simple error
   handling" (SJ Park)

   Refactor the DAMON core API functions to guarantee that all contexts
   are fully stopped when damon_start(), damon_stop(), or damon_commit()
   fail, eliminating the need for complex and error-prone caller-side
   cleanup code

 - "Keep tail page private zero at free and folio split" (Zi Yan)

   Add checks to ensure tail_page->private is zero when freeing compound
   or high-order pages and when promoting tail pages during large folio
   splits. By validating these fields at free and split time, it allows
   the removal of redundant private field clearing inside
   prep_compound_tail()

 - "mm: drop redundant lru_add_drain in anon folio reuse paths" (Barry
   Song)

   Eliminate redundant lru_add_drain() calls in
   wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock
   contention and system overhead

   By validating folio refcounts against the LRU cache before draining
   and removing unnecessary drains in the swap path, it achieves up to a
   30.5% reduction in drain calls during heavy swap workloads

 - "mm: clean up folio LRU and swap declarations" (Jianyue Wu)

   Reorganize folio LRU and swap code by relocating page-cluster state
   to mm/swap_state.c, renaming mm/swap.c to mm/folio.c, and moving
   MM-internal reclaim declarations into mm/internal.h.

 - "userfaultfd: working set tracking for VM guest memory" (Kiryl
   Shutsemau)

   Add userfaultfd support for tracking the working set of VM guest
   memory, so a VMM can identify hot pages and reclaim cold ones to
   tiered or remote storage

 - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 2)" (David
   Hildenbrand)

   Remove the remaining pieces of CONFIG_HAVE_BOOTMEM_INFO_NODE,
   performing some smaller cleanups around freeing of reserved vmemmap
   pages on the way.

 - "mm/damon: update probe hits for runtime parameter commits" (SJ Park)

   Ensure that DAMON's probe_hits attribute counter is properly updated
   when monitoring intervals are changed at runtime, matching the
   behavior of nr_accesses. To achieve this, it refactors and renames
   existing helper functions for shared use, applies the updates to
   probe_hits, and handles edge cases in damon_probe_hits_mvsum() to
   maintain measurement accuracy.

 - "KSM: performance optimizations for rmap_walk_ksm" (xu xin)

   Resolve a severe KSM reverse-mapping performance bottleneck where
   thousands of split VMAs sharing a single anon_vma cause extended lock
   contention.

   By adding an interval-filtering check during the rmap walk, it
   reduces worst-case anon_vma lock hold times from over 500ms down to
   under 2ms, preventing application freezes and latency spikes under
   memory pressure.

 - "mm: split a couple of headers from internal.h" (Mike Rapoport)

   Split declarations related to mm_init, memblock, vmalloc and sparse
   into new headers

 - "KSM: use linear_page_index in collect_procs_ksm()" (xu xin)

   Apply the interval tree optimization from rmap_walk_ksm() to
   collect_procs_ksm() to avoid iterating over non-matching VMAs during
   KSM memory error handling.

   It hoists loop-invariant address initialization and restricts the
   anon_vma_interval_tree_foreach walk to a targeted page offset range,
   reducing redundant checks and improving lookup efficiency.

 - "selftests/mm: avoid false failures in hugetlb and KSM tests" (Sayali
   Patil)

   Fix issues in the hugetlb and KSM MM selftest categories that can
   report failures when the prerequisites for the tests are not
   satisfied

 - "mm/damon: introduce data attributes only monitoring" (SJ Park)

   Introduce attribute-weighted region management in DAMON, allowing
   users to prioritize specific data attributes (such as page sizes or
   cgroups) over or instead of access monitoring.

   By assigning weights to attribute probes, DAMON can completely
   disable access tracking and adjust monitoring regions based on
   weighted probe-hit counters to optimize monitoring quality for
   attribute-focused workloads.

 - "mm/hmm: Add mmap lock-drop support for userfaultfd-backed mappings"
   (Stanislav Kinsburskii)

   Extend hmm_range_fault() to support userfaultfd-backed regions by
   allowing the mmap lock to be dropped during fault handling via a new
   hmm_range_fault_locked() helper.

   By accepting a locked pointer and signaling retry status when lock
   release occurs, it enables page fault resolution in userfaultfd
   regions while preserving backward compatibility for existing callers.

 - "mm: make VMA page offset handling more consistent" (Lorenzo Stoakes)

   Clean up and standardize how vma->vm_pgoff is accessed and
   manipulated across file-backed and anonymous mappings in the kernel

   It introduces dedicated helper functions such as vma_start_pgoff(),
   vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while
   renaming rmap interval tree helpers to better reflect their
   functionality.

   These changes establish a cleaner foundation for future work that
   will unify virtual page offset indexing for all anonymous and CoW'd
   folios.

 - "mm: handle device-private PMDs in walk callbacks" (Usama Arif)

   Address kernel panics and state corruption caused by MM walk
   callbacks reaching non-present device-private PMD swap entries
   created during HMM migrations

   It ensures that functions which acquire pmd_trans_huge_lock()
   properly recognize device-private PMDs instead of assuming a present
   THP or a standard migration entry.

 - "mm/rmap: Refactor try_to_unmap_one" (Dev Jain)

   Refactor try_to_unmap_one by modularizing Hugetlb,
   anonymous-lazyfree, and anonymous-swapbacked logic into dedicated
   functions, laying the structural groundwork for batched anonymous
   large folio unmapping.

 - "Docs/ABI/damon: sysfs ABI document fixes and additions" (Song Hu)

   Fix typos and fills in missing entries in the DAMON sysfs ABI
   document

 - "dax/kmem: atomic whole-device hotplug via sysfs" (Gregory Price)

   Introduce an atomic sysfs state attribute and supporting DAX/MM
   infrastructure to prevent userland races when offlining and removing
   entire memory regions

   By adding an unplugged state alongside standard online modes, it
   enables whole-device atomic hotplug control while preserving backward
   compatibility.

 - "mm: convert more vm_flags_t users to vma_flags_t" (Lorenzo Stoakes)

   Continue transitioning the kernel from the deprecated vm_flags_t type
   to vma_flags_t across core memory management infrastructure.

   It replaces legacy type usage in core functions such as do_mmap(),
   unmapped area allocation, mm->def_vma_flags, and VMA operations like
   mlock, mprotect, and mremap.

 - "Two small patches to clean up mm/mm_slot.h" (xu xin)

   Refactor mm_slot.h by introducing mm_slot_remove() to unify duplicate
   slot deletion sequences in khugepaged and KSM. It also adds code
   documentation explaining why mm_slot_lookup and mm_slot_insert must
   remain as preprocessor macros rather than static inline functions.

 - "mm/damon/core: hide core-private struct fields" (SJ Park)

   Clean up DAMON core structures by consistently marking internal-only
   fields with private: comment tags to prevent improper direct access
   from outer layers.

   It enforces encapsulation across core structures including
   damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to
   interact through approved access APIs instead of exposing raw struct
   members.

 - "mm/damon: unurgent fixes for infinite loop, NULL de-ref and races"
   (SJ Park)

   Address potential infinite loops, NULL dereferences, and race
   conditions identified in DAMON

   It fixes an infinite loop triggered by extreme user configurations, a
   NULL pointer dereference within unit tests and minor monitoring
   accuracy degradation caused by subtle runtime races.

 - "mm/page_alloc: fixes for free_pages_nolock() on RT/UP" (Brendan
   Jackman)

   Fix an NMI safety flaw in __free_frozen_pages() where freeing pages
   on non-SMP or PREEMPT_RT kernels can bypass can_spin_trylock() checks
   via non-PCP or isolated migration paths.

   It also resolves potential kernel crashes and privilege escalation
   risks triggered when BPF tracing runs in NMI context alongside memory
   hotplug or large allocation frees.

 - "mm/page_alloc: couple of followups for recent cleanups" (Brendan
   Jackman)

   Clean up and update page allocator nomenclature, documentation, and
   debug assertions.

   It aligns internal FPI_ flags with the public "nolock" naming
   convention, removes outdated internal implementation details from
   high-level page allocator comments, and eliminates obsolete
   VM_BUG_ON() assertions in allocation paths.

 - "mm/mseal: further cleanups" (Lorenzo Stoakes)

   Refactor and simplify the mseal implementation by clarifying API
   boundaries and removing unnecessary code complexity.

   It replaces generic do_mseal() usage outside the syscall with a
   dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO,
   eliminates mm_struct parameters to enforce that sealing applies only
   to current->mm, and streamlines overall logic and comments with no
   functional changes intended.

 - "mm/vmscan: fix swappiness=max and clean up per-node proactive
   reclaim" (Ridong Chen)

   Resolve reclaim behavior bugs and clean up function parameters across
   memory reclaim paths

   It fixes swappiness=max in both standard reclaim and MGLRU so
   unswappable anonymous memory no longer falls back to evicting page
   cache, ensures reclaim_store() returns accurate error codes instead
   of collapsing all failures into -EAGAIN, and removes the obsolete
   gfp_mask parameter from __node_reclaim().

 - "mm: mincore: misc cleanups" (Kefeng Wang)

   Clean up and simplifies the mincore code. Most importantly, it
   removes the historical special behavior that always reports VM_PFNMAP
   pages as non-resident.

 - "mm/huge_memory: drop dead split helper variants" (Kiryl Shutsemau)

   Two trivial cleanups in the folio split API

 - "mm/damon: fix uninitialized DAMOS field and kunit exec expectation
   bugs" (SJ Park)

   Resolve minor operational and testing bugs in DAMON identified by
   Sashiko. It initializes the damos->last_applied field to prevent
   occasional efficiency degradation and fixes invalid memory accesses
   in DAMON KUnit tests during test failure handling.

 - "cleanup for stable_page_flags()" (Jinjiang Tu)

   Clean up and refactor stable_page_flags() used by /proc/kpageflags
   without altering functionality.

   It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag
   bits, converts folio-specific flag checks to standard folio_test_*()
   helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling.

 - "Batch unmap of uffd-wp file folios" (Dev Jain)

   Extend batched folio unmapping support to file folios within
   userfaultfd write-protect (uffd-wp) VMAs by adding batching
   capabilities to pte_install_uffd_wp_if_needed().

   This removes special-case restrictions on uffd-wp VMAs in
   try_to_unmap_one(), significantly simplifying the function's control
   flow and complexity.

 - "mm/early_ioremap: clarify and clean up early_ioremap_reset()"
   (Sang-Heon Jeon)

   Clarify and clean up the architecture-specific usage of
   __late_set_fixmap() and __late_clear_fixmap() after
   early_ioremap_reset()

   It adds explicit documentation regarding when early_ioremap_reset()
   must be called and removes redundant macro definitions and reset
   calls in the RISC-V and ARM64 architectures.

 - "mm: fix reclaim storms in defrag_mode" (Johannes Weiner)

   Address severe performance regressions, swap storms, and spurious
   OOMs caused by vm.defrag_mode=1 under high memory pressure in Meta
   production

   It updates the page allocator slowpath so non-movable allocation
   requests actively trigger direct reclaim and direct compaction at
   pageblock_order scale, allowing them to claim whole pageblocks rather
   than spinning unproductively.

 - "zram: lockmap tweaks" (Sebastian Siewior)

   Optimize and fix lockdep tracking for zram devices by consolidating
   per-entry lockmaps and isolate lock classes across multiple instances

   This reduces memory overhead by replacing per-entry lockdep_map
   instances with a single map per struct zram, and assigns a dynamic
   lock_class_key to each instance to prevent false deadlock reports
   when different zram devices are backed by distinct filesystems.

* tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (501 commits)
  selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check
  selftests/mm: unpoison pages in memory-failure teardown
  mm/shmem: downgrade final i_blocks check in shmem_evict_inode() to pr_warn()
  mm/khugepaged: replace mutex_lock/mutex_unlock usage with guard macro
  mm/zsmalloc: fix release order of locks in zs_page_migrate()
  Documentation: zram: remove sections numbering
  ksm: stop iterating VMAs when ksm_test_exit returns true
  mm: fold userfaultfd_rwp() to false without CONFIG_ARCH_HAS_PTE_PROTNONE
  mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
  zram: use a custom key for each zram object
  zram: move lockmap to be per-zram instead per table
  selftests/mm: fix gup_longterm EINVAL error message
  mm: page_alloc: fix non-movable reclaim storm in defrag_mode
  mm: page_alloc: move capture_control to the page allocator
  mm: compaction: support non-movable compaction for pageblock requests
  mm: page_alloc: __GFP_FS lockdep annotation for direct compaction
  hugetlb: evaluate subpool free state while locked
  mm/damon: remove trailing semicolons after function definitions
  mm/damon/ops-common: prevent migration fallback to non-target nodes
  mm/damon: update outdated comment about DAMOS filter handling
  ...
2026-08-20 18:17:08 -07:00
Linus Torvalds
9d2ed026f0 Summary
* Documentation
 
   Fix kernel-doc warnings by adjusting in file documentation.
 
 * Consolidate do_proc_* function into do_proc_vec.
 
   Consolidate three slightly different implementations of applying a converter
   on all elements of a vector. Fixes to this function now propagate to the three
   types.
 
 * Miscellaneous
 
   Replaced CONFIG_PROC_SYSCTL with CONFIG_SYSCTL (they were the same) and
   restrict cad_pid modifications to global root (GLOBAL_ROOT_UID)
 
 * Testing
 
   This series was run through sysctl selftests/kunit test suite in x86_64. And
   went into linux-next around rc2, giving it a bit more than a month of testing.
 -----BEGIN PGP SIGNATURE-----
 
 iQGzBAABCgAdFiEErkcJVyXmMSXOyyeQupfNUreWQU8FAmp0ga8ACgkQupfNUreW
 QU9RZQv/UFBopK15/HcUPWAp8h0Yq68Reij0ryPhuOuoqRaWjLrz5iT9SvNW4IZH
 WfAHal9+gVyAov2TvZUDHE0iojYa1S7l1MSBSvzlEijZnbglnt+63Ijfria3FTr2
 FIqk7gOxCpDg7kRh1GkIm8yc6Ke7T2IcbMT8XW5PAs43QqMPgGfeUry14sr6H89u
 pc1vXS/PcRDdsKkYKADCuljGG3ywL/7frDhSRcc+5WkCACOujzosmXTL10TVVs7H
 6Lz3vujtQyCnv3UxlHicsJQXD60m2gqbCLcqa5gndfE5jO2nS3ZTqRBALT9Cimuk
 43k+cKgJwOa5ry9OFXmp+in57hgOg8AZqWWENY2W0RaU6Tw7Ui5x6z36ZtE5PR9u
 NlNAOprv6UnKOQ6Bc4GGtfSMh+EviqQBSNQroEz4UxLdrFx2X7SxkSgz5I6gLbzf
 w+KZpQ3Y3Kjvr9ywkQUftekWqaeapv/OfrjGXRwiIBYhlurmKqvFpjjSQXmjow9u
 RD1bfR9X
 =aYrQ
 -----END PGP SIGNATURE-----

Merge tag 'sysctl-7.03-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl

Pull sysctl updates from Joel Granados:

 - Fix kernel-doc warnings by adjusting in file documentation

 - Consolidate do_proc_* function into do_proc_vec

   Consolidate three slightly different implementations of applying a
   converter on all elements of a vector. Fixes to this function now
   propagate to the three types.

 - Replace CONFIG_PROC_SYSCTL with CONFIG_SYSCTL (they were the same)
   and restrict cad_pid modifications to global root (GLOBAL_ROOT_UID)

* tag 'sysctl-7.03-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl:
  sysctl: remove CONFIG_PROC_SYSCTL, it just mirrors CONFIG_SYSCTL
  sysctl: move the "cad_pid" entry from pid_table[] to kern_reboot_table[]
  sysctl: repair some kernel-doc comments
  sysctl: add Returns: kernel-doc for all functions
  sysctl: Update API function documentation
  sysctl: Rename proc_doulongvec_minmax_conv to proc_doulongvec_conv
  sysctl: Group proc_handler declarations and document
  sysctl: Replace do_proc_do{int,ulong,uint}vec with do_proc_vec
  sysctl: Add negp parameter to douintvec converter functions
  sysctl: Move default converter assignment out of do_proc_dointvec
2026-08-20 08:46:41 -07:00
Linus Torvalds
104a813376 VDSO updates:
- Consolidate the VDSO datastore further and provide support for
    mlock_all() and prefaulting.
 
  - Provide 32-bit legacy time related functionality only if
    CONFIG_COMPAT_32BIT_TIME is enabled. The config switch exists, but
    architecture code still exposes the legacy functionality even disabled.
 
    Clean this up by adding the missing guards and validating at build time
    that the VDSO is legacy free if disabled.
 
  - Consolidate the VDSO related config options in core and drivers, which
    removes some non-sensical dependencies and quite an amount of #ifdeffery.
 
  - Clean up the PAGE_SIZE definition maze
 -----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCgAuFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmqCxfkQHHRnbHhAa2Vy
 bmVsLm9yZwAKCRCmGPVMDXSYoSQkEADEOmcrm3vwMbaElrAfQRp4MOQMnDpKPCDa
 0EwdkXKJyqfOGx1PNKbcWZe10qShpXqyz+q3MUbHiOVh7KxkaGj0GOA/+xD+Tgs5
 RAFXCq+CY4Ccjix7vlyOBLvGgomuznAtRDCFprVq5OTXyQfVvS++5SHzaU/0xXiY
 ZZEInrFP61BEJ8LJycpoN5431EBcUX7XpSkr9eHtuSOslOBzbTEtBbDp0AjDGse0
 5qM/oZDufZDQQr31kVQiL0dN9bBWwdGNtBwZBjsf6KioY9M00LO0E9twSCSrI39F
 kgD2N97RDjTewu/zEe0fvCDVypqel2mBvjfiYU4c8g6pprdJ4Hq1qMcDAtMBUDBZ
 9jR8B09eYZwHLdbM5PFjiMf9d6p25P7X+twFI9Hylcm1YZtM4OTnamDhQOQDp1Fd
 QdrFevXg1zvYVi1rrDYarcPfg/tGsetOTujMQ1m50/AJZOoEdcX9jZR/wfdW8ti6
 X9TIn3SDzhauXkmeR86tHxtOmHDirVfBWCCCEyVT2YzGIIje25cf266fCPdcGRYl
 kzhtycg8LqpTRMWjhlaf56NtD9qQlbvDY8L23tQLJUYhDp8xOxqyuRPRdpJVM0b3
 4vp/Z8Sgz8tpEHO2ARsXfuu2CzilTBH0B2KL3f+a8CwpzIEadjIfc+6EEYqwgOAn
 +/RhckFp/A==
 =jHl1
 -----END PGP SIGNATURE-----

Merge tag 'timers-vdso-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull VDSO updates from Thomas Gleixner:

 - Consolidate the VDSO datastore further and provide support for
   mlock_all() and prefaulting.

 - Provide 32-bit legacy time related functionality only if
   CONFIG_COMPAT_32BIT_TIME is enabled. The config switch exists,
   but architecture code still exposes the legacy functionality even
   disabled.

   Clean this up by adding the missing guards and validating at build
   time that the VDSO is legacy free if disabled.

 - Consolidate the VDSO related config options in core and drivers,
   which removes some non-sensical dependencies and quite an amount of
   #ifdeffery.

 - Clean up the PAGE_SIZE definition maze

* tag 'timers-vdso-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  random: vDSO: Drop custom PAGE_SIZE definitions
  LoongArch: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/timer-riscv: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/arm_arch_timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/mips-gic-timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  MIPS: csrc-r4k: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  vDSO: Make clockmode constants available without CONFIG_GENERIC_GETTIMEOFDAY
  kbuild: Support generated asm-headers in subdirectories
  vdso: Rename HAVE_GENERIC_VDSO to VDSO_DATASTORE
  vdso: Drop HAVE_GENERIC_VDSO from architecture kconfig files
  vdso: Automatically select HAVE_GENERIC_VDSO if necessary
  MIPS: vdso: Stop using CONFIG_HAVE_GENERIC_VDSO
  vdso: Remove the dependency on HAVE_GENERIC_VDSO from ARCH_HAS_VDSO_ARCH_DATA
  futex: Remove dependency on HAVE_GENERIC_VDSO from FUTEX_ROBUST_UNLOCK
  vdso/gettimeofday: Verify COMPAT_32BIT_TIME interactions
  sparc: vdso: Respect COMPAT_32BIT_TIME
  MIPS: VDSO: Respect COMPAT_32BIT_TIME
  powerpc/vdso: Respect COMPAT_32BIT_TIME
  ARM: VDSO: Respect COMPAT_32BIT_TIME
  arm64: vdso32: Respect COMPAT_32BIT_TIME
  ...
2026-08-18 16:56:25 -07:00
Heiko Carstens
3484440a7b s390/preempt: Enable HAS_SEPARATE_PREEMPT_RESCHED_BITS
Convert s390's preempt_count to 64 bit, and change the preempt
primitives accordingly.

[boqun: Apply the corrected comment for asm block]
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Boqun Feng <boqun@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260804161447.84806-13-boqun@kernel.org
2026-08-10 10:50:20 +02:00
Oleg Nesterov
8d75c338f0 sysctl: remove CONFIG_PROC_SYSCTL, it just mirrors CONFIG_SYSCTL
CONFIG_SYSCTL used to make sense as a separate hidden bool before commit
61a47c1ad3 ("sysctl: Remove the sysctl system call"); it was selected
by both CONFIG_SYSCTL_SYSCALL and CONFIG_PROC_SYSCTL.

Today CONFIG_PROC_SYSCTL is the only selector, so the two are always
equal. Kill the hidden bool, rename the PROC_SYSCTL prompt to SYSCTL,
and s/CONFIG_PROC_SYSCTL/CONFIG_SYSCTL/ tree-wide.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Joel Granados <joel.granados@kernel.org>
2026-08-05 15:28:23 +02:00
Heiko Carstens
e54228ad8f s390/Kconfig: Select ARCH_SUPPORTS_CFI
With all prerequisites in place select ARCH_SUPPORTS_CFI.

Note that this support is supposed to work with the generic kCFI support
which is provided by clang. This comes with a couple of limitations:

The generic kCFI implementation does not generate a .kcfi_traps section,
nor is a special instruction used in case a checksum mismatch is detected.

This means in case of checksum mismatch the kernel just crashes. It should
be quite easy to tell by the surrounding code that a crash happened because
of a checksum mismatch.

If clang and/or gcc provide a .kcfi_traps section it will be possible to
print proper CFI messages instead of just crashing the kernel (enable
ARCH_USES_CFI_TRAPS).

In addition this also means that CFI_PERMISSIVE does not work. Even if the
option is selected the kernel will crash in case of checksum mismatch.

However it seems to be acceptable to enable kCFI support to the kernel now
even if it is not perfect. Later clang and gcc extensions are required to
improve this.

As of now a crash caused by a CFI failure looks like this:

illegal operation: 0001 ilc:1 [#1]SMP
Modules linked in: bpf_testmod(OE)
CPU: 0 UID: 0 PID: 92 Comm: test_progs Tainted: G           OE       7.2.0-rc4-00021-gc35ed7a1ca22-dirty #3 PREEMPTLAZY
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: IBM 3931 A01 703 (KVM/Linux)
Krnl PSW : 0704e00180000000 00000166d4853a0a (bpf_task_work_callback+0x176/0x290)
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
Krnl GPRS: 0400000069b02e96 000001665471856c 0000000084dc1000 000000008084da58
           000000008084da60 000000005ff492bf 0000000000000000 00000000809de300
           fffffffffff7ffff 00000000000a0337 00000000809e4d00 000000008437b100
           00000000801bc288 00000000801bc280 00000166d48538fc 000000e6d502ba90
Krnl Code: 00000166d48539fa: e320c0400004       lg      %r2,64(%r12)
           00000166d4853a00: e340c0480004       lg      %r4,72(%r12)
          *00000166d4853a06: a7640001           brc     6,00000166d4853a08
          >00000166d4853a0a: 0de1               basr    %r14,%r1
           00000166d4853a0c: e300b6580095       llh     %r0,1624(%r11)
           00000166d4853a12: ec040009027e       cij     %r0,2,4,00000166d4853a24
           00000166d4853a18: a70affff           ahi     %r0,-1
           00000166d4853a1c: 4000b658           sth     %r0,1624(%r11)
Call Trace:
 [<00000166d4853a0a>] bpf_task_work_callback+0x176/0x290
...

The disassembly contains the brc instruction (branch into the instruction
itself with two byte offset to execute an illegal instruction, and the
following basr instruction used for an indirect branch.

Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:16:54 +02:00
Kiryl Shutsemau (Meta)
c6f11553c0 mm: decouple protnone helpers from CONFIG_NUMA_BALANCING
Patch series "userfaultfd: working set tracking for VM guest memory", v10.

This series adds userfaultfd support for tracking the working set of VM
guest memory, so a VMM can identify hot pages and reclaim cold ones to
tiered or remote storage.


This patch (of 15):

pte_protnone() and pmd_protnone() detect present-but-inaccessible page
table entries.  This capability is useful beyond NUMA balancing -- for
example, userfaultfd working set tracking uses protnone PTEs to track page
access without unmapping pages.

Introduce CONFIG_ARCH_HAS_PTE_PROTNONE to decouple the protnone PTE
infrastructure from CONFIG_NUMA_BALANCING.  The six architectures that
support protnone PTEs (x86_64, arm64, powerpc, s390, riscv, loongarch) now
select this option, and CONFIG_NUMA_BALANCING depends on it.

No functional change -- the same set of architectures continues to have
working protnone support, but the infrastructure is now available
independently of NUMA balancing.

Link: https://lore.kernel.org/20260708111417.173443-1-kirill@shutemov.name
Link: https://lore.kernel.org/20260708111417.173443-2-kirill@shutemov.name
Signed-off-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
Assisted-by: Claude:claude-opus-4-6
Acked-by: SeongJae Park <sj@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: James Houghton <jthoughton@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04 19:18:36 -07:00
Aneesh Kumar K.V (Arm)
f38ab0d7f5 s390: Expose protected virtualization through cc_platform_has()
Protected virtualization guests use memory encryption, so advertise that to
the rest of the kernel through cc_platform_has(CC_ATTR_MEM_ENCRYPT).

s390 already forces DMA mappings to be unencrypted for protected
virtualization guests through force_dma_unencrypted(). Add
ARCH_HAS_CC_PLATFORM and provide the matching cc_platform_has()
implementation

Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Matthew Rosato <mjrosato@linux.ibm.com>
Cc: Jaehoon Kim <jhkim@linux.ibm.com>
Tested-by: Jaehoon Kim <jhkim@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
Link: https://lore.kernel.org/r/20260717180442.110954-7-aneesh.kumar@kernel.org
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2026-07-31 08:40:58 +02:00
Usama Arif
d547b10017 mm: rename ARCH_ENABLE_THP_MIGRATION to ARCH_HAS_PMD_SOFTLEAVES
CONFIG_ARCH_ENABLE_THP_MIGRATION gates PMD-level migration entries. 
PMD-level device-private entries use the same migration mechanism and
therefore require the same architecture support.

Upcoming PMD-level swap entries can use the same PMD softleaf helpers
without depending on page migration, so rename the architecture gate to
CONFIG_ARCH_HAS_PMD_SOFTLEAVES.  This describes the PMD entry capability
rather than one current user of it.

This is a pure rename: the set of selecting architectures (x86, arm64,
s390, riscv, loongarch, and powerpc on PPC_BOOK3S_64) and the gating
semantics are unchanged.

No functional change intended.

Link: https://lore.kernel.org/20260706114320.1643046-7-usama.arif@linux.dev
Signed-off-by: Usama Arif <usama.arif@linux.dev>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <baoquan.he@linux.dev>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Kiryl Shutsemau <kas@kernel.org>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-30 19:40:25 -07:00
Heiko Carstens
656db30220 s390: Add support for DCACHE_WORD_ACCESS (again)
Implement load_unaligned_zeropad() and enable DCACHE_WORD_ACCESS to
speed up string operations in fs/dcache.c and fs/namei.c.

With the secure storage access exception cases addressed, add support
for DCACHE_WORD_ACCESS again.

Tested-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-30 00:29:11 +02:00
Jaehoon Kim
14ddf10e93 s390: Select SWIOTLB_DYNAMIC and DMA_COHERENT_POOL
SWIOTLB_DYNAMIC allows the SWIOTLB to grow on demand when the initial
bounce-buffer area is exhausted, instead of relying only on the pool
reserved at boot. This improves behavior under sustained I/O pressure.

In testing, exhaustion of the initial SWIOTLB area was observed under
real workloads such as large file transfers and package installation
workloads, where continued availability of bounce buffering was needed
to avoid guest-visible I/O stalls or failures.

When the current SWIOTLB capacity is exhausted, the dynamic expansion
path schedules asynchronous pool growth and then attempts immediate
non-blocking allocation of transient bounce-buffer memory.

In that path, the current implementation uses the generic DMA coherent
atomic pool for transient bounce-buffer allocations. Selecting
DMA_COHERENT_POOL together with SWIOTLB_DYNAMIC on s390 makes that
atomic fallback path available.

The coherent atomic pool is a generic DMA facility. By default, its size
is 128 KiB per 1 GiB of memory, with a minimum default size of 128 KiB,
and it can be adjusted with the coherent_pool= kernel parameter. The pool
itself can be exhausted, so this improves behavior under pressure, but
does not guarantee that DMA mappings will always succeed.

Select both options from s390 Kconfig so this support is available by
default on s390 systems.

Signed-off-by: Jaehoon Kim <jhkim@linux.ibm.com>
Acked-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Tested-by: Joshua Daley <jdaley@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-30 00:29:07 +02:00
Thomas Weißschuh
52447180f4 vdso: Drop HAVE_GENERIC_VDSO from architecture kconfig files
Now that GENERIC_GETTIMEOFDAY and VDSO_GETRANDOM enable
HAVE_GENERIC_VDSO automatically, the architecture specific kconfig files
do not need to do so anymore.

Remove the corresponding lines.

Keep them for riscv, loongarch and powerpc as those have their own
explicit usage of the vDSO datastore provided by HAVE_GENERIC_VDSO.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://patch.msgid.link/20260709-vdso-have_generic_vdso-v1-5-d2e1061f268b@linutronix.de
2026-07-15 10:49:03 +02:00
Mete Durlu
01c162e27a s390/idle: Introduce cpuidle for s390
Introduce generic cpuidle driver on s390. Use a two stage approach to
handle idle scenarios and use idle governor for idle stage selection.
Two stages are, from shallow to deep, idle polling and enabled wait.

Suggested-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Mete Durlu <meted@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Christian Loehle <christian.loehle@arm.com>
Acked-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-08 17:03:28 +02:00
Linus Torvalds
25a01b5155 s390 updates for 7.2 merge window
- Use CIO device online variable instead of the internal FSM state to
   determine device availability during purge operations
 
 - Remove extra check of task_stack_page() because try_get_task_stack()
   already takes care of that when reading /proc/<pid>/wchan
 
 - Allow user-space to use the new SCLP action qualifier 4 for to
   provide NVMe SMART log data to the platform.
 
 - Send AP CHANGE uevents on successful bind and successful association
   to notify user-space about SE operations on AP queue devices
 
 - Add an s390dbf kernel parameter to configure debug log levels and
   area sizes during early boot
 
 - On arm64 the empty zero page is going to be mapped read-only.
   Do the same for s390 with an explicit set_memory_ro() call
 
 - Improve s390-specific bcr_serialize() and cpu_relax() implementations
 
 - Remove all unused variables to avoid allmodconfig W=1 build fails
   with latest clang-23
 
 - Cleanup default Kconfig values for s390 selftests
 
 - Add a s390-tod trace clock to allow comparing trace timestamps
   between different systems or virtual machines on s390
 
 - Remove the s390 implementation of strlcat() in favor of the
   generic variant
 
 - Make consistent the calling order between page_table_check_pte_clear()
   and secure page conversion across all code paths
 
 - Rearrange some fields within AP and zcrypt structs to reduce
   memory consumption and unused holes
 
 - Shorten GR_NUM and VX_NUM macros and move them to a separate header
 
 - Replace __get_free_page() with kmalloc() in few sources
 
 - Introduce an infrastructure for more efficient this_cpu operations.
   Eliminate conditional branches when PREEMPT_NONE is removed
 
 - Enable Rust support
 
 - Use z10 as minimum architecture level, similar to the boot code,
   to enforce a defined architecture level set
 
 - Improve and convert various mem*() helper functions to C. For that
   add .noinstr.text section to avoid orphaned warnings from the linker
 
 - Fix the function pointer type in __ret_from_fork() to correct
   the indirect call to match kernel thread return type of int
 
 - Revert support for DCACHE_WORD_ACCESS to avoid an endless exception
   loop on read from donated Ultravisor pages at unaligned addresses
 -----BEGIN PGP SIGNATURE-----
 
 iI0EABYKADUWIQQrtrZiYVkVzKQcYivNdxKlNrRb8AUCai/rTRccYWdvcmRlZXZA
 bGludXguaWJtLmNvbQAKCRDNdxKlNrRb8KNOAPwMpGVtXcKF4HftCv49X0WpqKbU
 tdYO9hbq9wanIGpgIgEAk5vggxe74pj+palTbtCDteVjDpnSp811x8gfmLlPrgU=
 =qzZ2
 -----END PGP SIGNATURE-----

Merge tag 's390-7.2-1' of gitolite.kernel.org:pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Alexander Gordeev:

 - Use CIO device online variable instead of the internal FSM state to
   determine device availability during purge operations

 - Remove extra check of task_stack_page() because try_get_task_stack()
   already takes care of that when reading /proc/<pid>/wchan

 - Allow user-space to use the new SCLP action qualifier 4 for to
   provide NVMe SMART log data to the platform.

 - Send AP CHANGE uevents on successful bind and successful association
   to notify user-space about SE operations on AP queue devices

 - Add an s390dbf kernel parameter to configure debug log levels and
   area sizes during early boot

 - On arm64 the empty zero page is going to be mapped read-only. Do the
   same for s390 with an explicit set_memory_ro() call

 - Improve s390-specific bcr_serialize() and cpu_relax() implementations

 - Remove all unused variables to avoid allmodconfig W=1 build fails
   with latest clang-23

 - Cleanup default Kconfig values for s390 selftests

 - Add a s390-tod trace clock to allow comparing trace timestamps
   between different systems or virtual machines on s390

 - Remove the s390 implementation of strlcat() in favor of the generic
   variant

 - Make consistent the calling order between
   page_table_check_pte_clear() and secure page conversion across all
   code paths

 - Rearrange some fields within AP and zcrypt structs to reduce memory
   consumption and unused holes

 - Shorten GR_NUM and VX_NUM macros and move them to a separate header

 - Replace __get_free_page() with kmalloc() in few sources

 - Introduce an infrastructure for more efficient this_cpu operations.
   Eliminate conditional branches when PREEMPT_NONE is removed

 - Enable Rust support

 - Use z10 as minimum architecture level, similar to the boot code, to
   enforce a defined architecture level set

 - Improve and convert various mem*() helper functions to C. For that
   add .noinstr.text section to avoid orphaned warnings from the linker

 - Fix the function pointer type in __ret_from_fork() to correct the
   indirect call to match kernel thread return type of int

 - Revert support for DCACHE_WORD_ACCESS to avoid an endless exception
   loop on read from donated Ultravisor pages at unaligned addresses

* tag 's390-7.2-1' of gitolite.kernel.org:pub/scm/linux/kernel/git/s390/linux: (52 commits)
  s390: Revert support for DCACHE_WORD_ACCESS
  s390/process: Fix kernel thread function pointer type
  s390/tishift: Convert __ashlti3(), __ashrti3(), __lshrti3() to C
  s390/memmove: Optimize backward copy case
  s390/string: Convert memset(16|32|64)() to C
  s390/string: Convert memcpy() to C
  s390/string: Convert memset() to C
  s390/string: Convert memmove() to C
  s390/string: Add -ffreestanding compile option to string.o
  s390: Add .noinstr.text to boot and purgatory linker scripts
  s390/purgatory: Enforce z10 minimum architecture level
  s390: Enable Rust support
  s390/cmpxchg: Fix KASAN stack-out-of-bounds in atomic helpers
  rust: helpers: Add memchr wrapper for string operations
  rust/bindgen_parameters: Mark s390 types as opaque to prevent repr conflicts
  s390/jump_label: Implement ARCH_STATIC_BRANCH_JUMP_ASM and ARCH_STATIC_BRANCH_ASM macros
  s390/bug: Provide ARCH_WARN_ASM for Rust WARN/BUG support
  s390/ap: Fix locking issue in SE bind and associate sysfs functions
  s390/percpu: Provide arch_this_cpu_write() implementation
  s390/percpu: Provide arch_this_cpu_read() implementation
  ...
2026-06-16 05:08:13 +05:30
Linus Torvalds
186d3c4e92 A series of updates for the VDSO:
- Remove the redundant CONFIG_GENERIC_TIME_VSYSCALL after converting the
     remaining users over.
 
   - Rework and sanitize the MIPS VDSO handling, so it does not handle the
     time related VDSO if there is no VDSO capable clocksource available.
     Also stop mapping VDSO data pages unconditionally even if there is no
     usage possible.
 -----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCgAuFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmotog4QHHRnbHhAa2Vy
 bmVsLm9yZwAKCRCmGPVMDXSYoYD5D/41UOOboDxkv3Ei0gS12RfFL/pHWPotWMvA
 eUS4Ohko2pYubZB+iv87QQD5HC6TBN9yXbUjpvS0wN9jVSlXgQOdJ0JkNYYbPfjH
 nsBt7g/ksCA0Tv0KxnUUtECCTu6frtXkSi5iDU03DVNvxLMDmRaXg+D10TKGiCfb
 q1g2IoenA6YWz8pUkwOSI5wInepN8Dt9s5VXRsBQS9J9Uin/ZWAIwghIEhfFPNZu
 braNUSyJ+A7xISipOjWD1kEfBjcUzr24AuMZ9XHpxnykdWoa57qNEoTnjm+bVWpU
 hK0ED4nXSM8qxioV1Kye0h+hUi0T7amNtq6OSfAL+oXWHINvUe2PybqK+sZ1pPFb
 0MSP/J4mV9CIvriPA33fTXw/VxigI/puCMtGuSLLXHwh2xW8hadz7wGU9lqF4E7E
 f+X9NYqZSmx/82z0KKPFtIQyfrozquRBzy2ZiUloh7ek7GKF5tvuN8lds3Ghuf/6
 9Hqr/YquG1Zuu+j95ozVIm7fhDjmMktxAwyAbg5WkNGqOEw7MyhoUGXjKKG29uLa
 PRitT9DklL5vndzjizkLc1C2DuC++OhpnJCqRWOjJ9/TbvBC6Rn6aKwYyVTFX9xM
 4VauNLQg0q9uG0TyW6o3aakaFk9OIKT+vl7bWO0G4g2YZaKDOs7s+b9sdNNNQq5R
 lTL5F0KUCQ==
 =Z90m
 -----END PGP SIGNATURE-----

Merge tag 'timers-vdso-2026-06-13' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip

Pull vdso updates from Thomas Gleixner:

 - Remove the redundant CONFIG_GENERIC_TIME_VSYSCALL after converting
   the remaining users over.

 - Rework and sanitize the MIPS VDSO handling, so it does not handle the
   time related VDSO if there is no VDSO capable clocksource available.
   Also stop mapping VDSO data pages unconditionally even if there is no
   usage possible.

* tag 'timers-vdso-2026-06-13' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip:
  MIPS: VDSO: Fold MIPS_CLOCK_VSYSCALL into MIPS_GENERIC_GETTIMEOFDAY
  MIPS: VDSO: Gate microMIPS restriction on GCC version
  MIPS: VDSO: Fold MIPS_DISABLE_VDSO into MIPS_GENERIC_GETTIMEOFDAY
  clocksource/drivers/mips-gic-timer: Only use VDSO_CLOCKMODE_GIC when it is a available
  MIPS: csrc-r4k: Only use VDSO_CLOCKMODE_R4K when it is a available
  MIPS: VDSO: Only map the data pages when the vDSO is used
  MIPS: Introduce Kconfig MIPS_GENERIC_GETTIMEOFDAY
  vdso/datastore: Always provide symbol declarations
  MAINTAINERS: Add include/linux/vdso_datastore.h to vDSO block
  vdso/gettimeofday: Rename __arch_get_vdso_u_timens_data()
  vdso/treewide: Drop GENERIC_TIME_VSYSCALL
  vdso/vsyscall: Gate update_vsyscall() behind CONFIG_GENERIC_GETTIMEOFDAY
  riscv: vdso: Drop CONFIG_GENERIC_TIME_VSYSCALL guard around syscall fallbacks
2026-06-15 13:57:13 +05:30
Heiko Carstens
37540b8c28 s390: Revert support for DCACHE_WORD_ACCESS
load_unaligned_zeropad() reads eight bytes from unaligned addresses and may
cross page boundaries. It handles exceptions which may happen if reading
from the second page results in an exception.

For pages which are donated to the Ultravisor for secure execution purposes
the do_secure_storage_access() exception handler however does not handle
such exceptions correctly. Such an exception may result in an endless
exception loop which will never be resolved.

An attempt to fix this [1] turned out to be not sufficient. For now revert
load_unaligned_zeropad() until this problem has been resolved in a proper
way.

Note that the implementation of load_unaligned_zeropad() itself is
correct. The revert is just a temporary workaround until there is complete
fix for secure storage access exceptions.

[1] commit b00be77302 ("s390/mm: Add missing secure storage access fixups for donated memory")

Fixes: 802ba53eef ("s390: add support for DCACHE_WORD_ACCESS")
Cc: stable@vger.kernel.org
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-12 11:30:25 +02:00
Alexander Gordeev
982c89c9b9 Merge branch 'rust-for-s390' into features
Jan Polensky says:

===================
Rust support on s390 requires a small set of architecture-specific pieces
before the generic Rust kernel infrastructure can be used.

The series wires up s390 as a Rust-capable 64-bit architecture, adds the
missing assembly interfaces needed by Rust for WARN/BUG reporting and for
static branches, adjusts bindgen parameters to avoid repr layout conflicts
caused by packed and aligned s390 structures, and fixes issues discovered
during testing.

s390 currently requires rustc with support for -Zpacked-stack, and the
minimum tool version gating is adjusted accordingly.

Link: https://github.com/Rust-for-Linux/linux/issues/2

Tested against: rustc 1.96.0 (ac68faa20 2026-05-25)
===================

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-10 16:53:23 +02:00
Jan Polensky
3f70ebe638 s390: Enable Rust support
Enable building Rust code on s390 by wiring the architecture into the
kernel Rust infrastructure.

Add s390 to the Rust arch support documentation, provide the s390 Rust
target and required compiler flags, and set the bindgen target for
arch/s390. Adjust the Rust target generation and minimum rustc version
gating so the s390 setup is handled explicitly.

The Rust toolchain uses the "s390x" triple naming for the 64 bit target.

Rust support is currently incompatible with CONFIG_EXPOLINE, which
relies on compiler support for the -mindirect-branch= and
-mfunction_return= options. Therefore, select HAVE_RUST only when
EXPOLINE is disabled.

Acked-by: Miguel Ojeda <ojeda@kernel.org>
Acked-by: Gary Guo <gary@garyguo.net>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jan Polensky <japo@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-10 16:25:13 +02:00
Heiko Carstens
1f57f68c4d s390: Remove GENERIC_LOCKBREAK Kconfig option
s390 selects GENERIC_LOCKBREAK if PREEMPT is enabled. Reason is a historic
18 years old commit [1] which fixed a compile error for PREEMPT enabled
kernels. Back than only PREEMPT_NONE and PREEMPT_VOLUNTARY kernels were
considered to be important for s390. PREEMPT should "just work".

However, since recently PREEMPT is always enabled [2], which also causes
GENERIC_LOCKBREAK to be always enabled. For some workloads this leads to
massive performance degradation; e.g. a simple kernel compile on machines
with many CPUs may take up to four times longer.

To fix this just remove the GENERIC_LOCKBREAK from s390's Kconfig, since
the compile error from 18 years ago does not exist anymore.

[1] commit b6b40c532a ("[S390] Define GENERIC_LOCKBREAK.")
[2] commit 7dadeaa6e8 ("sched: Further restrict the preemption modes")

Cc: stable@vger.kernel.org
Reported-by: Massimiliano Pellizzer <massimiliano.pellizzer@canonical.com>
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-08 18:59:07 +02:00
Thomas Weißschuh
96942092d5 vdso/treewide: Drop GENERIC_TIME_VSYSCALL
This Kconfig symbol is not used anymore, remove it.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260519-vdso-generic_time_vsyscal-v1-3-5c2a5905d5f5@linutronix.de
2026-06-02 21:41:23 +02:00
Julian Braha
30cc5e2ad8 s390/Kconfig: Cleanup defaults for selftests
Remove unconditional 'n' defaults from def_tristate statements,
as they override the later 'KUNIT_ALL_TESTS' default, rendering
it dead Kconfig code.

This dead code was identified by kconfirm, a static analysis tool
for Kconfig.

Also include S390_KPROBES_SANITY_TEST in KUNIT_ALL_TESTS.

Signed-off-by: Julian Braha <julianbraha@gmail.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-26 08:15:40 +02:00
Peter Oberparleiter
a2cec68637 s390/debug: Add s390dbf kernel parameter
Problem determination using s390dbf logging sometimes requires changing
the default logging level or log area size. While this is possible
using sysfs interfaces, there is no easy way to adjust these parameters
for early boot code that emits logs before userspace is available.

Add an s390dbf kernel parameter to address this shortcoming. The
parameter can be used to specify log level and area size (in units of
pages). A level of '-' turns logging off for an area. Logs can be
identified by name or a shell-style pattern.

Parameter format:

  s390dbf=<name|pattern>:[<level>|-]:[<pages>][,...]

Example:

  s390dbf=cio*:6:128,sclp_err::2

Specified parameters are applied immediately during debug area
registration for regular log areas. For early, static debug areas,
log levels are changed during early_param() parsing, while size
changes are applied at arch_initcall-time.

Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Tested-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-11 16:42:31 +02:00
Linus Torvalds
2a4c0c11c0 s390 updates for 7.1 merge window
- Add support for CONFIG_PAGE_TABLE_CHECK and enable it in
   debug_defconfig. s390 can only tell user from kernel PTEs via the mm,
   so mm_struct is now passed into pxx_user_accessible_page() callbacks
 
 - Expose the PCI function UID as an arch-specific slot attribute in
   sysfs so a function can be identified by its user-defined id while
   still in standby. Introduces a generic ARCH_PCI_SLOT_GROUPS hook in
   drivers/pci/slot.c
 
 - Refresh s390 PCI documentation to reflect current behavior and cover
   previously undocumented sysfs attributes
 
 - zcrypt device driver cleanup series: consistent field types, clearer
   variable naming, a kernel-doc warning fix, and a comment explaining
   the intentional synchronize_rcu() in pkey_handler_register()
 
 - Provide an s390 arch_raw_cpu_ptr() that avoids the detour via
   get_lowcore() using alternatives, shrinking defconfig by ~27 kB
 
 - Guard identity-base randomization with kaslr_enabled() so nokaslr
   keeps the identity mapping at 0 even with
   CONFIG_RANDOMIZE_IDENTITY_BASE=y
 
 - Build S390_MODULES_SANITY_TEST as a module only by requiring
   KUNIT && m, since built-in would not exercise module loading
 
 - Remove the permanently commented-out HMCDRV_DEV_CLASS create_class()
   code in the hmcdrv driver
 
 - Drop stale ident_map_size extern conflicting with asm/page.h
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCgAdFiEE3QHqV+H2a8xAv27vjYWKoQLXFBgFAmno78kACgkQjYWKoQLX
 FBiHbggAmW5hPIDf4F8HLomMREaaQb7QAyYwfeefwhcFUXSMu8td8S68aN4UkOnS
 DGSFjb+V6Nqd+ewrF7IS9pRU9YFsmBqo3MnLdcJ/ojZFz8BlwoAi+E4AD1a38hY2
 9zh2siPBMjydqBRUn6zjsK8auk4e8r44iS5MNNMXDF2ePE/PnPKTm93GhbtnnM6r
 a7mQkiPbi6j0sN/UU+pQkhS4fm2XNaGpCGGX0W0v2RdLIYZ9zQQdg4TaEsjQ5wZA
 OC3P8LG3OyJjnxsY2J8PIKK0VM0JP67KUGnQOi1y8HbN1LkFfAWF6CK7tsyUE/JM
 TYg7ENs2mUMmaa8niOGkiXzjjAxD0g==
 =NpmP
 -----END PGP SIGNATURE-----

Merge tag 's390-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add support for CONFIG_PAGE_TABLE_CHECK and enable it in
   debug_defconfig. s390 can only tell user from kernel PTEs via the mm,
   so mm_struct is now passed into pxx_user_accessible_page() callbacks

 - Expose the PCI function UID as an arch-specific slot attribute in
   sysfs so a function can be identified by its user-defined id while
   still in standby. Introduces a generic ARCH_PCI_SLOT_GROUPS hook in
   drivers/pci/slot.c

 - Refresh s390 PCI documentation to reflect current behavior and cover
   previously undocumented sysfs attributes

 - zcrypt device driver cleanup series: consistent field types, clearer
   variable naming, a kernel-doc warning fix, and a comment explaining
   the intentional synchronize_rcu() in pkey_handler_register()

 - Provide an s390 arch_raw_cpu_ptr() that avoids the detour via
   get_lowcore() using alternatives, shrinking defconfig by ~27 kB

 - Guard identity-base randomization with kaslr_enabled() so nokaslr
   keeps the identity mapping at 0 even with RANDOMIZE_IDENTITY_BASE=y

 - Build S390_MODULES_SANITY_TEST as a module only by requiring KUNIT &&
   m, since built-in would not exercise module loading

 - Remove the permanently commented-out HMCDRV_DEV_CLASS create_class()
   code in the hmcdrv driver

 - Drop stale ident_map_size extern conflicting with asm/page.h

* tag 's390-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/zcrypt: Fix warning about wrong kernel doc comment
  PCI: s390: Expose the UID as an arch specific PCI slot attribute
  docs: s390/pci: Improve and update PCI documentation
  s390/pkey: Add comment about synchronize_rcu() to pkey base
  s390/hmcdrv: Remove commented out code
  s390/zcrypt: Slight rework on the agent_id field
  s390/zcrypt: Explicitly use a card variable in _zcrypt_send_cprb
  s390/zcrypt: Rework MKVP fields and handling
  s390/zcrypt: Make apfs a real unsigned int field
  s390/zcrypt: Rework domain processing within zcrypt device driver
  s390/zcrypt: Move inline function rng_type6cprb_msgx from header to code
  s390/percpu: Provide arch_raw_cpu_ptr()
  s390: Enable page table check for debug_defconfig
  s390/pgtable: Add s390 support for page table check
  s390/pgtable: Use set_pmd_bit() to invalidate PMD entry
  mm/page_table_check: Pass mm_struct to pxx_user_accessible_page()
  s390/boot: Respect kaslr_enabled() for identity randomization
  s390/Kconfig: Make modules sanity test a module-only option
  s390/setup: Drop stale ident_map_size declaration
2026-04-22 11:13:45 -07:00
Linus Torvalds
9cdca33667 integrity-v7.1
-----BEGIN PGP SIGNATURE-----
 
 iIoEABYKADIWIQQdXVVFGN5XqKr1Hj7LwZzRsCrn5QUCad/SPRQcem9oYXJAbGlu
 dXguaWJtLmNvbQAKCRDLwZzRsCrn5TDuAQCT+OttUlEqKfGLUrmXjsqw+BdgSm59
 vOwTUfY0uIjAsgEAzFY8bOt5WWud9bpfEE3iarKIZQI0RidSHylyaB4FRg8=
 =6soG
 -----END PGP SIGNATURE-----

Merge tag 'integrity-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity

Pull integrity updates from Mimi Zohar:
 "There are two main changes, one feature removal, some code cleanup,
  and a number of bug fixes.

  Main changes:
   - Detecting secure boot mode was limited to IMA. Make detecting
     secure boot mode accessible to EVM and other LSMs
   - IMA sigv3 support was limited to fsverity. Add IMA sigv3 support
     for IMA regular file hashes and EVM portable signatures

  Remove:
   - Remove IMA support for asychronous hash calculation originally
     added for hardware acceleration

  Cleanup:
   - Remove unnecessary Kconfig CONFIG_MODULE_SIG and CONFIG_KEXEC_SIG
     tests
   - Add descriptions of the IMA atomic flags

  Bug fixes:
   - Like IMA, properly limit EVM "fix" mode
   - Define and call evm_fix_hmac() to update security.evm
   - Fallback to using i_version to detect file change for filesystems
     that do not support STATX_CHANGE_COOKIE
   - Address missing kernel support for configured (new) TPM hash
     algorithms
   - Add missing crypto_shash_final() return value"

* tag 'integrity-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  evm: Enforce signatures version 3 with new EVM policy 'bit 3'
  integrity: Allow sigv3 verification on EVM_XATTR_PORTABLE_DIGSIG
  ima: add support to require IMA sigv3 signatures
  ima: add regular file data hash signature version 3 support
  ima: Define asymmetric_verify_v3() to verify IMA sigv3 signatures
  ima: remove buggy support for asynchronous hashes
  integrity: Eliminate weak definition of arch_get_secureboot()
  ima: Add code comments to explain IMA iint cache atomic_flags
  ima_fs: Correctly create securityfs files for unsupported hash algos
  ima: check return value of crypto_shash_final() in boot aggregate
  ima: Define and use a digest_size field in the ima_algo_desc structure
  powerpc/ima: Drop unnecessary check for CONFIG_MODULE_SIG
  ima: efi: Drop unnecessary check for CONFIG_MODULE_SIG/CONFIG_KEXEC_SIG
  ima: fallback to using i_version to detect file change
  evm: fix security.evm for a file with IMA signature
  s390: Drop unnecessary CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT
  evm: Don't enable fix mode when secure boot is enabled
  integrity: Make arch_ima_get_secureboot integrity-wide
2026-04-17 15:42:01 -07:00
David Hildenbrand (Arm)
078f80f909 mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE
Patch series "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
CONFIG_MIGRATION".

While working on memory hotplug code cleanups, I realized that
CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE is not really required anymore.

Changing that revealed some rather nasty looking CONFIG_MIGRATION
handling.

Let's clean that up by introducing a dedicated CONFIG_NUMA_MIGRATION
option and reducing the dependencies that CONFIG_MIGRATION has.


This patch (of 2):

All architectures that select CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE also
select CONFIG_ARCH_ENABLE_MEMORY_HOTPLUG.  So we can just remove
CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE.

For CONFIG_MIGRATION, make it depend on CONFIG_MEMORY_HOTREMOVE instead,
and make CONFIG_MEMORY_HOTREMOVE select CONFIG_MIGRATION (just like
CONFIG_CMA and CONFIG_COMPACTION already do).

We'll clean up CONFIG_MIGRATION next.

Link: https://lkml.kernel.org/r/20260319-config_migration-v1-0-42270124966f@kernel.org
Link: https://lkml.kernel.org/r/20260319-config_migration-v1-1-42270124966f@kernel.org
Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Reviewed-by: Joshua Hahn <joshua.hahnjy@gmail.com>
Reviewed-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:33 -07:00
Nathan Chancellor
7caedbb5ad integrity: Eliminate weak definition of arch_get_secureboot()
security/integrity/secure_boot.c contains a single __weak function,
which breaks recordmcount when building with clang:

  $ make -skj"$(nproc)" ARCH=powerpc LLVM=1 ppc64_defconfig security/integrity/secure_boot.o
  Cannot find symbol for section 2: .text.
  security/integrity/secure_boot.o: failed

Introduce a Kconfig symbol, CONFIG_HAVE_ARCH_GET_SECUREBOOT, to indicate
that an architecture provides a definition of arch_get_secureboot().
Provide a static inline stub when this symbol is not defined to achieve
the same effect as the __weak function, allowing secure_boot.c to be
removed altogether. Move the s390 definition of arch_get_secureboot()
out of the CONFIG_KEXEC_FILE block to ensure it is always available, as
it does not actually depend on KEXEC_FILE.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 31a6a07eef ("integrity: Make arch_ima_get_secureboot integrity-wide")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2026-03-13 11:37:13 -04:00
Vasily Gorbik
7bbf70131f Merge branch 'page-table-check-support' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux into features
Add s390 support for CONFIG_PAGE_TABLE_CHECK.

* 'page-table-check-support' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390: Enable page table check for debug_defconfig
  s390/pgtable: Add s390 support for page table check
  s390/pgtable: Use set_pmd_bit() to invalidate PMD entry
  mm/page_table_check: Pass mm_struct to pxx_user_accessible_page()

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-13 00:13:51 +01:00
Tobias Huschle
7b4dde5e40 s390/pgtable: Add s390 support for page table check
Add page table check hooks into routines that modify user page
tables.

Unlike other architectures s390 does not have means to distinguish
between kernel and user page table entries. Rely on the fact the
page table check infrastructure itself operates on non-init_mm
memory spaces only.

Use the provided mm_struct to verify that the memory space is not
init_mm (aka not the kernel memory space) indeed. That check is
supposed to be succeeded already (on some code paths even twice).

If the passed memory space by contrast is init_mm that would be an
unexpected semantical change in generic code, so do VM_BUG_ON() in
such case.

Unset _SEGMENT_ENTRY_READ bit to indicate that pmdp_invalidate()
was applied against a huge PMD and is going to be updated by
set_pmd_at() shortly. The hook pmd_user_accessible_page() should
skip such entries until that, otherwise the page table accounting
falls apart and BUG_ON() gets hit as result.

The invalidated huge PMD entry should not be confused with a PROT_NONE
entry as reported by pmd_protnone(), though the entry characteristics
exactly match: _SEGMENT_ENTRY_LARGE is set while _SEGMENT_ENTRY_READ is
unset. Since pmd_protnone() implementation depends on NUMA_BALANCING
configuration option, it should not be used in pmd_user_accessible_page()
check, which is expected to be CONFIG_NUMA_BALANCING-agnostic.

Nevertheless, an invalidated huge PMD is technically still pmd_protnone()
entry and it should not break other code paths once _SEGMENT_ENTRY_READ
is unset. As of now, all pmd_protnone() checks are done under page table
locks or exercise GUP-fast and HMM code paths, which are expected to be
safe against concurrent page table updates.

Alternative approach would be using the last remaining unused PMD entry
bit 0x800 to indicate that pmdp_invalidate() was called on a PMD. That
would allow avoiding collisions with pmd_protnone() handling code paths,
but saving the bit is more preferable way to go.

Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Tobias Huschle <huschle@linux.ibm.com>
Co-developed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/r/4db8a681205bd555298d62441cdcfca43317a35a.1772812343.git.agordeev@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-13 00:07:47 +01:00
Vasily Gorbik
20216c126b s390/Kconfig: Make modules sanity test a module-only option
The modules sanity test must be built as a module to actually exercise
module loading. Require KUNIT && m to prevent built-in builds and avoid
misuse, so it is either 'n' or 'm'.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-03-05 21:08:50 +01:00
Coiby Xu
a2e507afd9 s390: Drop unnecessary CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT
Commit b5ca117365 ("ima: prevent kexec_load syscall based on runtime
secureboot flag") and commit 268a784049 ("s390/kexec_file: Disable
kexec_load when IPLed secure") disabled the kexec_load syscall based
on the secureboot mode. Commit 9e2b4be377 ("ima: add a new CONFIG
for loading arch-specific policies") needed to detect the secure boot
mode, not to load an IMA architecture specific policy. Since there is
the new CONFIG_INTEGRITY_SECURE_BOOT, drop
CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT for s390.

Signed-off-by: Coiby Xu <coxu@redhat.com>
Tested-by: Alexander Egorenkov <egorenar@linux.ibm.com>
[Vasily Gorbik: Fix missing arch_get_secureboot() prototype warning]
link: https://lore.kernel.org/linux-integrity/c00-01.ttbfdx5@ub.hpns/
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2026-03-05 11:15:10 -05:00
Linus Torvalds
9806790115 s390 fixes for 7.0 merge window
- Make KEXEC_SIG available again for CONFIG_MODULES=n
 
 - The s390 topology code used to call rebuild_sched_domains() before common
   code scheduling domains were setup. This was silently ignored by common
   code, but now results in a warning. Address by avoiding the early call
 
 - Convert debug area lock from spinlock to raw spinlock to address lockdep
   warnings
 
 - The recent 3490 tape device driver rework resulted in a different device
   driver name, which is visible via sysfs for user space. This breaks at
   least one user space application. Change the device driver name back to
   its old name to fix this
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEECMNfWEw3SLnmiLkZIg7DeRspbsIFAmmYUo8ACgkQIg7DeRsp
 bsL+rw//f6AadV9X3tCPe/vaNdxQWkVtd1Ov+eKYkIohSFvghBo4+4c6qXlsc4jp
 Opedqs2+YUdx2/tR3nTPkfG/Nm49rGpB+i4CYAjBUlAjIN1czyUlvICJ6ZVQbpQt
 zR+I7Ej/QsBR0XMqbUfPNWMwbdZlW395kXNhCAKckbjM1M+Hezp9WZjuaQ1vWCUv
 wGXAUI+/fTgPKUu3nIQRw2JkG2M+IfFj3jkYMXTW8D8WzoqLXPwtjmjcDtTU/VDr
 otq97rDUd8MvNsxV5hX+T7nI0JQIFrdb32bCy0mhWhnvc7rHdewLfp5+793vKG/K
 DcOouXr/vJcPUhAUQI3ksREAwAEJV1phKeILXbbUhpkAZUQAozVG6+YrzMk/4VSW
 Zm6BGcOLVo0DQtn97I55gKSPFiNoCQwSdU+CcrbzA8aEDBMfxLFKBvh50sAx/0I3
 zXbXYDjgPdqOKuyUprB8Y6PJTrCnHebXPGs2Kgl2XU3k4m61h/60EHIXe6w0ErM8
 1hl8+Rdn4jmWDcAOFKTBpo8Y/o+WZVcNssPr4F7ArcjJTWmAtxWP3NQAux3UM2HW
 3dOV6dcdbmndKSmKwtWrvMVv0GvcgWAp/NhjwKx37EovYLFJg4DqtiioqiOFjWKD
 4gwIB8gKxbWjNSGq3cKTiH021iWoRIDoCeAFJWRdrH5xt7rxCWc=
 =7EJS
 -----END PGP SIGNATURE-----

Merge tag 's390-7.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Heiko Carstens:

 - Make KEXEC_SIG available again for CONFIG_MODULES=n

 - The s390 topology code used to call rebuild_sched_domains() before
   common code scheduling domains were setup. This was silently ignored
   by common code, but now results in a warning. Address by avoiding the
   early call

 - Convert debug area lock from spinlock to raw spinlock to address
   lockdep warnings

 - The recent 3490 tape device driver rework resulted in a different
   device driver name, which is visible via sysfs for user space. This
   breaks at least one user space application. Change the device driver
   name back to its old name to fix this

* tag 's390-7.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/tape: Fix device driver name
  s390/debug: Convert debug area lock from a spinlock to a raw spinlock
  s390/smp: Avoid calling rebuild_sched_domains() early
  s390/kexec: Make KEXEC_SIG available when CONFIG_MODULES=n
2026-02-20 09:24:45 -08:00
Alexander Egorenkov
dd3411959b s390/kexec: Make KEXEC_SIG available when CONFIG_MODULES=n
The commit c8424e776b ("MODSIGN: Export module signature definitions")
replaced the dependency of KEXEC_SIG on SYSTEM_DATA_VERIFICATION with the
dependency on MODULE_SIG_FORMAT. This change disables KEXEC_SIG in s390
kernels built with MODULES=n if nothing else selects MODULE_SIG_FORMAT.

Furthermore, the signature verification in s390 kexec does not require
MODULE_SIG_FORMAT because it requires only the struct module_signature and,
therefore, does not depend on code in kernel/module_signature.c.

But making ARCH_SUPPORTS_KEXEC_SIG depend on SYSTEM_DATA_VERIFICATION is
also incorrect because it makes KEXEC_SIG available on s390 only if some
other arbitrary option (for instance a file system or device driver)
selects it directly or indirectly.

To properly make KEXEC_SIG available for s390 kernels built with MODULES=y
as well as MODULES=n _and_ also not depend on arbitrary options selecting
SYSTEM_DATA_VERIFICATION, set ARCH_SUPPORTS_KEXEC_SIG=y for s390 and select
SYSTEM_DATA_VERIFICATION when KEXEC_SIG=y.

Fixes: c8424e776b ("MODSIGN: Export module signature definitions")
Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-02-17 15:49:03 +01:00
Linus Torvalds
cb5573868e Loongarch:
- Add more CPUCFG mask bits.
 
 - Improve feature detection.
 
 - Add lazy load support for FPU and binary translation (LBT) register state.
 
 - Fix return value for memory reads from and writes to in-kernel devices.
 
 - Add support for detecting preemption from within a guest.
 
 - Add KVM steal time test case to tools/selftests.
 
 ARM:
 
 - Add support for FEAT_IDST, allowing ID registers that are not
   implemented to be reported as a normal trap rather than as an UNDEF
   exception.
 
 - Add sanitisation of the VTCR_EL2 register, fixing a number of
   UXN/PXN/XN bugs in the process.
 
 - Full handling of RESx bits, instead of only RES0, and resulting in
   SCTLR_EL2 being added to the list of sanitised registers.
 
 - More pKVM fixes for features that are not supposed to be exposed to
   guests.
 
 - Make sure that MTE being disabled on the pKVM host doesn't give it
   the ability to attack the hypervisor.
 
 - Allow pKVM's host stage-2 mappings to use the Force Write Back
   version of the memory attributes by using the "pass-through'
   encoding.
 
 - Fix trapping of ICC_DIR_EL1 on GICv5 hosts emulating GICv3 for the
   guest.
 
 - Preliminary work for guest GICv5 support.
 
 - A bunch of debugfs fixes, removing pointless custom iterators stored
   in guest data structures.
 
 - A small set of FPSIMD cleanups.
 
 - Selftest fixes addressing the incorrect alignment of page
   allocation.
 
 - Other assorted low-impact fixes and spelling fixes.
 
 RISC-V:
 
 - Fixes for issues discoverd by KVM API fuzzing in
   kvm_riscv_aia_imsic_has_attr(), kvm_riscv_aia_imsic_rw_attr(),
   and kvm_riscv_vcpu_aia_imsic_update()
 
 - Allow Zalasr, Zilsd and Zclsd extensions for Guest/VM
 
 - Transparent huge page support for hypervisor page tables
 
 - Adjust the number of available guest irq files based on MMIO
   register sizes found in the device tree or the ACPI tables
 
 - Add RISC-V specific paging modes to KVM selftests
 
 - Detect paging mode at runtime for selftests
 
 s390:
 
 - Performance improvement for vSIE (aka nested virtualization)
 
 - Completely new memory management.  s390 was a special snowflake that enlisted
   help from the architecture's page table management to build hypervisor
   page tables, in particular enabling sharing the last level of page
   tables.  This however was a lot of code (~3K lines) in order to support
   KVM, and also blocked several features.  The biggest advantages is
   that the page size of userspace is completely independent of the
   page size used by the guest: userspace can mix normal pages, THPs and
   hugetlbfs as it sees fit, and in fact transparent hugepages were not
   possible before.  It's also now possible to have nested guests and
   guests with huge pages running on the same host.
 
 - Maintainership change for s390 vfio-pci
 
 - Small quality of life improvement for protected guests
 
 x86:
 
 - Add support for giving the guest full ownership of PMU hardware (contexted
   switched around the fastpath run loop) and allowing direct access to data
   MSRs and PMCs (restricted by the vPMU model).  KVM still intercepts
   access to control registers, e.g. to enforce event filtering and to
   prevent the guest from profiling sensitive host state.  This is more
   accurate, since it has no risk of contention and thus dropped events, and
   also has significantly less overhead.
 
   For more information, see the commit message for merge commit bf2c3138ae
   ("Merge tag 'kvm-x86-pmu-6.20' of https://github.com/kvm-x86/linux into HEAD").
 
 - Disallow changing the virtual CPU model if L2 is active, for all the same
   reasons KVM disallows change the model after the first KVM_RUN.
 
 - Fix a bug where KVM would incorrectly reject host accesses to PV MSRs
   when running with KVM_CAP_ENFORCE_PV_FEATURE_CPUID enabled, even if those
   were advertised as supported to userspace,
 
 - Fix a bug with protected guest state (SEV-ES/SNP and TDX) VMs, where KVM
   would attempt to read CR3 configuring an async #PF entry.
 
 - Fail the build if EXPORT_SYMBOL_GPL or EXPORT_SYMBOL is used in KVM (for x86
   only) to enforce usage of EXPORT_SYMBOL_FOR_KVM_INTERNAL.  Only a few exports
   that are intended for external usage, and those are allowed explicitly.
 
 - When checking nested events after a vCPU is unblocked, ignore -EBUSY instead
   of WARNing.  Userspace can sometimes put the vCPU into what should be an
   impossible state, and spurious exit to userspace on -EBUSY does not really
   do anything to solve the issue.
 
 - Also throw in the towel and drop the WARN on INIT/SIPI being blocked when vCPU
   is in Wait-For-SIPI, which also resulted in playing whack-a-mole with syzkaller
   stuffing architecturally impossible states into KVM.
 
 - Add support for new Intel instructions that don't require anything beyond
   enumerating feature flags to userspace.
 
 - Grab SRCU when reading PDPTRs in KVM_GET_SREGS2.
 
 - Add WARNs to guard against modifying KVM's CPU caps outside of the intended
   setup flow, as nested VMX in particular is sensitive to unexpected changes
   in KVM's golden configuration.
 
 - Add a quirk to allow userspace to opt-in to actually suppress EOI broadcasts
   when the suppression feature is enabled by the guest (currently limited to
   split IRQCHIP, i.e. userspace I/O APIC).  Sadly, simply fixing KVM to honor
   Suppress EOI Broadcasts isn't an option as some userspaces have come to rely
   on KVM's buggy behavior (KVM advertises Supress EOI Broadcast irrespective
   of whether or not userspace I/O APIC supports Directed EOIs).
 
 - Clean up KVM's handling of marking mapped vCPU pages dirty.
 
 - Drop a pile of *ancient* sanity checks hidden behind in KVM's unused
   ASSERT() macro, most of which could be trivially triggered by the guest
   and/or user, and all of which were useless.
 
 - Fold "struct dest_map" into its sole user, "struct rtc_status", to make it
   more obvious what the weird parameter is used for, and to allow fropping
   these RTC shenanigans if CONFIG_KVM_IOAPIC=n.
 
 - Bury all of ioapic.h, i8254.h and related ioctls (including
   KVM_CREATE_IRQCHIP) behind CONFIG_KVM_IOAPIC=y.
 
 - Add a regression test for recent APICv update fixes.
 
 - Handle "hardware APIC ISR", a.k.a. SVI, updates in kvm_apic_update_apicv()
   to consolidate the updates, and to co-locate SVI updates with the updates
   for KVM's own cache of ISR information.
 
 - Drop a dead function declaration.
 
 - Minor cleanups.
 
 x86 (Intel):
 
 - Rework KVM's handling of VMCS updates while L2 is active to temporarily
   switch to vmcs01 instead of deferring the update until the next nested
   VM-Exit.  The deferred updates approach directly contributed to several
   bugs, was proving to be a maintenance burden due to the difficulty in
   auditing the correctness of deferred updates, and was polluting
   "struct nested_vmx" with a growing pile of booleans.
 
 - Fix an SGX bug where KVM would incorrectly try to handle EPCM page faults,
   and instead always reflect them into the guest.  Since KVM doesn't shadow
   EPCM entries, EPCM violations cannot be due to KVM interference and
   can't be resolved by KVM.
 
 - Fix a bug where KVM would register its posted interrupt wakeup handler even
   if loading kvm-intel.ko ultimately failed.
 
 - Disallow access to vmcb12 fields that aren't fully supported, mostly to
   avoid weirdness and complexity for FRED and other features, where KVM wants
   enable VMCS shadowing for fields that conditionally exist.
 
 - Print out the "bad" offsets and values if kvm-intel.ko refuses to load (or
   refuses to online a CPU) due to a VMCS config mismatch.
 
 x86 (AMD):
 
 - Drop a user-triggerable WARN on nested_svm_load_cr3() failure.
 
 - Add support for virtualizing ERAPS.  Note, correct virtualization of ERAPS
   relies on an upcoming, publicly announced change in the APM to reduce the
   set of conditions where hardware (i.e. KVM) *must* flush the RAP.
 
 - Ignore nSVM intercepts for instructions that are not supported according to
   L1's virtual CPU model.
 
 - Add support for expedited writes to the fast MMIO bus, a la VMX's fastpath
   for EPT Misconfig.
 
 - Don't set GIF when clearing EFER.SVME, as GIF exists independently of SVM,
   and allow userspace to restore nested state with GIF=0.
 
 - Treat exit_code as an unsigned 64-bit value through all of KVM.
 
 - Add support for fetching SNP certificates from userspace.
 
 - Fix a bug where KVM would use vmcb02 instead of vmcb01 when emulating VMLOAD
   or VMSAVE on behalf of L2.
 
 - Misc fixes and cleanups.
 
 x86 selftests:
 
 - Add a regression test for TPR<=>CR8 synchronization and IRQ masking.
 
 - Overhaul selftest's MMU infrastructure to genericize stage-2 MMU support,
   and extend x86's infrastructure to support EPT and NPT (for L2 guests).
 
 - Extend several nested VMX tests to also cover nested SVM.
 
 - Add a selftest for nested VMLOAD/VMSAVE.
 
 - Rework the nested dirty log test, originally added as a regression test for
   PML where KVM logged L2 GPAs instead of L1 GPAs, to improve test coverage
   and to hopefully make the test easier to understand and maintain.
 
 guest_memfd:
 
 - Remove kvm_gmem_populate()'s preparation tracking and half-baked hugepage
   handling.  SEV/SNP was the only user of the tracking and it can do it via
   the RMP.
 
 - Retroactively document and enforce (for SNP) that KVM_SEV_SNP_LAUNCH_UPDATE
   and KVM_TDX_INIT_MEM_REGION require the source page to be 4KiB aligned, to
   avoid non-trivial complexity for something that no known VMM seems to be
   doing and to avoid an API special case for in-place conversion, which
   simply can't support unaligned sources.
 
 - When populating guest_memfd memory, GUP the source page in common code and
   pass the refcounted page to the vendor callback, instead of letting vendor
   code do the heavy lifting.  Doing so avoids a looming deadlock bug with
   in-place due an AB-BA conflict betwee mmap_lock and guest_memfd's filemap
   invalidate lock.
 
 Generic:
 
 - Fix a bug where KVM would ignore the vCPU's selected address space when
   creating a vCPU-specific mapping of guest memory.  Actually this bug
   could not be hit even on x86, the only architecture with multiple
   address spaces, but it's a bug nevertheless.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCgAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmmNqwwUHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroPaZAf/cJx5B67lnST272esz0j29MIuT/Ti
 jnf6PI9b7XubKYOtNvlu5ZW4Jsa5dqRG0qeO/JmcXDlwBf5/UkWOyvqIXyiuTl0l
 KcSUlKPtTgKZSoZpJpTppuuDE8FSYqEdcCmjNvoYzcJoPjmaeJbK6aqO0AkBbb6e
 L5InrLV7nV9iua6rFvA0s/G8/Eq2DG8M9hTRHe6NcI/z4hvslOudvpUXtC8Jygoo
 cV8vFavUwc+atrmvhAOLvSitnrjfNa4zcG6XMOlwXPfIdvi3zqTlQTgUpwGKiAGQ
 RIDUVZ/9bcWgJqbPRsdEWwaYRkNQWc5nmrAHRpEEaYV/NeBBNf4v6qfKSw==
 =SkJ1
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "Loongarch:

   - Add more CPUCFG mask bits

   - Improve feature detection

   - Add lazy load support for FPU and binary translation (LBT) register
     state

   - Fix return value for memory reads from and writes to in-kernel
     devices

   - Add support for detecting preemption from within a guest

   - Add KVM steal time test case to tools/selftests

  ARM:

   - Add support for FEAT_IDST, allowing ID registers that are not
     implemented to be reported as a normal trap rather than as an UNDEF
     exception

   - Add sanitisation of the VTCR_EL2 register, fixing a number of
     UXN/PXN/XN bugs in the process

   - Full handling of RESx bits, instead of only RES0, and resulting in
     SCTLR_EL2 being added to the list of sanitised registers

   - More pKVM fixes for features that are not supposed to be exposed to
     guests

   - Make sure that MTE being disabled on the pKVM host doesn't give it
     the ability to attack the hypervisor

   - Allow pKVM's host stage-2 mappings to use the Force Write Back
     version of the memory attributes by using the "pass-through'
     encoding

   - Fix trapping of ICC_DIR_EL1 on GICv5 hosts emulating GICv3 for the
     guest

   - Preliminary work for guest GICv5 support

   - A bunch of debugfs fixes, removing pointless custom iterators
     stored in guest data structures

   - A small set of FPSIMD cleanups

   - Selftest fixes addressing the incorrect alignment of page
     allocation

   - Other assorted low-impact fixes and spelling fixes

  RISC-V:

   - Fixes for issues discoverd by KVM API fuzzing in
     kvm_riscv_aia_imsic_has_attr(), kvm_riscv_aia_imsic_rw_attr(), and
     kvm_riscv_vcpu_aia_imsic_update()

   - Allow Zalasr, Zilsd and Zclsd extensions for Guest/VM

   - Transparent huge page support for hypervisor page tables

   - Adjust the number of available guest irq files based on MMIO
     register sizes found in the device tree or the ACPI tables

   - Add RISC-V specific paging modes to KVM selftests

   - Detect paging mode at runtime for selftests

  s390:

   - Performance improvement for vSIE (aka nested virtualization)

   - Completely new memory management. s390 was a special snowflake that
     enlisted help from the architecture's page table management to
     build hypervisor page tables, in particular enabling sharing the
     last level of page tables. This however was a lot of code (~3K
     lines) in order to support KVM, and also blocked several features.
     The biggest advantages is that the page size of userspace is
     completely independent of the page size used by the guest:
     userspace can mix normal pages, THPs and hugetlbfs as it sees fit,
     and in fact transparent hugepages were not possible before. It's
     also now possible to have nested guests and guests with huge pages
     running on the same host

   - Maintainership change for s390 vfio-pci

   - Small quality of life improvement for protected guests

  x86:

   - Add support for giving the guest full ownership of PMU hardware
     (contexted switched around the fastpath run loop) and allowing
     direct access to data MSRs and PMCs (restricted by the vPMU model).

     KVM still intercepts access to control registers, e.g. to enforce
     event filtering and to prevent the guest from profiling sensitive
     host state. This is more accurate, since it has no risk of
     contention and thus dropped events, and also has significantly less
     overhead.

     For more information, see the commit message for merge commit
     bf2c3138ae ("Merge tag 'kvm-x86-pmu-6.20' ...")

   - Disallow changing the virtual CPU model if L2 is active, for all
     the same reasons KVM disallows change the model after the first
     KVM_RUN

   - Fix a bug where KVM would incorrectly reject host accesses to PV
     MSRs when running with KVM_CAP_ENFORCE_PV_FEATURE_CPUID enabled,
     even if those were advertised as supported to userspace,

   - Fix a bug with protected guest state (SEV-ES/SNP and TDX) VMs,
     where KVM would attempt to read CR3 configuring an async #PF entry

   - Fail the build if EXPORT_SYMBOL_GPL or EXPORT_SYMBOL is used in KVM
     (for x86 only) to enforce usage of EXPORT_SYMBOL_FOR_KVM_INTERNAL.
     Only a few exports that are intended for external usage, and those
     are allowed explicitly

   - When checking nested events after a vCPU is unblocked, ignore
     -EBUSY instead of WARNing. Userspace can sometimes put the vCPU
     into what should be an impossible state, and spurious exit to
     userspace on -EBUSY does not really do anything to solve the issue

   - Also throw in the towel and drop the WARN on INIT/SIPI being
     blocked when vCPU is in Wait-For-SIPI, which also resulted in
     playing whack-a-mole with syzkaller stuffing architecturally
     impossible states into KVM

   - Add support for new Intel instructions that don't require anything
     beyond enumerating feature flags to userspace

   - Grab SRCU when reading PDPTRs in KVM_GET_SREGS2

   - Add WARNs to guard against modifying KVM's CPU caps outside of the
     intended setup flow, as nested VMX in particular is sensitive to
     unexpected changes in KVM's golden configuration

   - Add a quirk to allow userspace to opt-in to actually suppress EOI
     broadcasts when the suppression feature is enabled by the guest
     (currently limited to split IRQCHIP, i.e. userspace I/O APIC).
     Sadly, simply fixing KVM to honor Suppress EOI Broadcasts isn't an
     option as some userspaces have come to rely on KVM's buggy behavior
     (KVM advertises Supress EOI Broadcast irrespective of whether or
     not userspace I/O APIC supports Directed EOIs)

   - Clean up KVM's handling of marking mapped vCPU pages dirty

   - Drop a pile of *ancient* sanity checks hidden behind in KVM's
     unused ASSERT() macro, most of which could be trivially triggered
     by the guest and/or user, and all of which were useless

   - Fold "struct dest_map" into its sole user, "struct rtc_status", to
     make it more obvious what the weird parameter is used for, and to
     allow fropping these RTC shenanigans if CONFIG_KVM_IOAPIC=n

   - Bury all of ioapic.h, i8254.h and related ioctls (including
     KVM_CREATE_IRQCHIP) behind CONFIG_KVM_IOAPIC=y

   - Add a regression test for recent APICv update fixes

   - Handle "hardware APIC ISR", a.k.a. SVI, updates in
     kvm_apic_update_apicv() to consolidate the updates, and to
     co-locate SVI updates with the updates for KVM's own cache of ISR
     information

   - Drop a dead function declaration

   - Minor cleanups

  x86 (Intel):

   - Rework KVM's handling of VMCS updates while L2 is active to
     temporarily switch to vmcs01 instead of deferring the update until
     the next nested VM-Exit.

     The deferred updates approach directly contributed to several bugs,
     was proving to be a maintenance burden due to the difficulty in
     auditing the correctness of deferred updates, and was polluting
     "struct nested_vmx" with a growing pile of booleans

   - Fix an SGX bug where KVM would incorrectly try to handle EPCM page
     faults, and instead always reflect them into the guest. Since KVM
     doesn't shadow EPCM entries, EPCM violations cannot be due to KVM
     interference and can't be resolved by KVM

   - Fix a bug where KVM would register its posted interrupt wakeup
     handler even if loading kvm-intel.ko ultimately failed

   - Disallow access to vmcb12 fields that aren't fully supported,
     mostly to avoid weirdness and complexity for FRED and other
     features, where KVM wants enable VMCS shadowing for fields that
     conditionally exist

   - Print out the "bad" offsets and values if kvm-intel.ko refuses to
     load (or refuses to online a CPU) due to a VMCS config mismatch

  x86 (AMD):

   - Drop a user-triggerable WARN on nested_svm_load_cr3() failure

   - Add support for virtualizing ERAPS. Note, correct virtualization of
     ERAPS relies on an upcoming, publicly announced change in the APM
     to reduce the set of conditions where hardware (i.e. KVM) *must*
     flush the RAP

   - Ignore nSVM intercepts for instructions that are not supported
     according to L1's virtual CPU model

   - Add support for expedited writes to the fast MMIO bus, a la VMX's
     fastpath for EPT Misconfig

   - Don't set GIF when clearing EFER.SVME, as GIF exists independently
     of SVM, and allow userspace to restore nested state with GIF=0

   - Treat exit_code as an unsigned 64-bit value through all of KVM

   - Add support for fetching SNP certificates from userspace

   - Fix a bug where KVM would use vmcb02 instead of vmcb01 when
     emulating VMLOAD or VMSAVE on behalf of L2

   - Misc fixes and cleanups

  x86 selftests:

   - Add a regression test for TPR<=>CR8 synchronization and IRQ masking

   - Overhaul selftest's MMU infrastructure to genericize stage-2 MMU
     support, and extend x86's infrastructure to support EPT and NPT
     (for L2 guests)

   - Extend several nested VMX tests to also cover nested SVM

   - Add a selftest for nested VMLOAD/VMSAVE

   - Rework the nested dirty log test, originally added as a regression
     test for PML where KVM logged L2 GPAs instead of L1 GPAs, to
     improve test coverage and to hopefully make the test easier to
     understand and maintain

  guest_memfd:

   - Remove kvm_gmem_populate()'s preparation tracking and half-baked
     hugepage handling. SEV/SNP was the only user of the tracking and it
     can do it via the RMP

   - Retroactively document and enforce (for SNP) that
     KVM_SEV_SNP_LAUNCH_UPDATE and KVM_TDX_INIT_MEM_REGION require the
     source page to be 4KiB aligned, to avoid non-trivial complexity for
     something that no known VMM seems to be doing and to avoid an API
     special case for in-place conversion, which simply can't support
     unaligned sources

   - When populating guest_memfd memory, GUP the source page in common
     code and pass the refcounted page to the vendor callback, instead
     of letting vendor code do the heavy lifting. Doing so avoids a
     looming deadlock bug with in-place due an AB-BA conflict betwee
     mmap_lock and guest_memfd's filemap invalidate lock

  Generic:

   - Fix a bug where KVM would ignore the vCPU's selected address space
     when creating a vCPU-specific mapping of guest memory. Actually
     this bug could not be hit even on x86, the only architecture with
     multiple address spaces, but it's a bug nevertheless"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (267 commits)
  KVM: s390: Increase permitted SE header size to 1 MiB
  MAINTAINERS: Replace backup for s390 vfio-pci
  KVM: s390: vsie: Fix race in acquire_gmap_shadow()
  KVM: s390: vsie: Fix race in walk_guest_tables()
  KVM: s390: Use guest address to mark guest page dirty
  irqchip/riscv-imsic: Adjust the number of available guest irq files
  RISC-V: KVM: Transparent huge page support
  RISC-V: KVM: selftests: Add Zalasr extensions to get-reg-list test
  RISC-V: KVM: Allow Zalasr extensions for Guest/VM
  KVM: riscv: selftests: Add riscv vm satp modes
  KVM: riscv: selftests: add Zilsd and Zclsd extension to get-reg-list test
  riscv: KVM: allow Zilsd and Zclsd extensions for Guest/VM
  RISC-V: KVM: Skip IMSIC update if vCPU IMSIC state is not initialized
  RISC-V: KVM: Fix null pointer dereference in kvm_riscv_aia_imsic_rw_attr()
  RISC-V: KVM: Fix null pointer dereference in kvm_riscv_aia_imsic_has_attr()
  RISC-V: KVM: Remove unnecessary 'ret' assignment
  KVM: s390: Add explicit padding to struct kvm_s390_keyop
  KVM: LoongArch: selftests: Add steal time test case
  LoongArch: KVM: Add paravirt vcpu_is_preempted() support in guest side
  LoongArch: KVM: Add paravirt preempt feature in hypervisor side
  ...
2026-02-13 11:31:15 -08:00
Claudio Imbrenda
728b0e21b4 KVM: S390: Remove PGSTE code from linux/s390 mm
Remove the PGSTE config option.
Remove all code from linux/s390 mm that involves PGSTEs.

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
2026-02-04 17:00:10 +01:00
Claudio Imbrenda
e38c884df9 KVM: s390: Switch to new gmap
Switch KVM/s390 to use the new gmap code.

Remove includes to <gmap.h> and include "gmap.h" instead; fix all the
existing users of the old gmap functions to use the new ones instead.

Fix guest storage key access functions to work with the new gmap.

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
2026-02-04 17:00:10 +01:00
Gerd Bayer
0d453ba040 s390/Kconfig: Define non-zero ILLEGAL_POINTER_VALUE
Define CONFIG_ILLEGAL_POINTER_VALUE to the eye-catching non-zero value
of 0xdead000000000000, consistent with other architectures. Assert at
compile-time that the poison pointers that include/linux/poison.h
defines based on this illegal pointer are beyond the largest useful
virtual addresses. Also, assert at compile-time that the range of poison
pointers per include/linux/poison.h (currently a range of less than
0x10000 addresses) does not overlap with the range used for address
handles for s390's non-MIO PCI instructions.

This enables s390 to track the DMA mappings by the network stack's
page_pool that was introduced with [0]. Other functional changes are not
intended.

Other archictectures have introduced this for various other reasons with
commit 5c178472af ("riscv: define ILLEGAL_POINTER_VALUE for 64bit")
commit f6853eb561 ("powerpc/64: Define ILLEGAL_POINTER_VALUE for 64-bit")
commit bf0c4e0473 ("arm64: kconfig: Move LIST_POISON to a safe value")
commit a29815a333 ("core, x86: make LIST_POISON less deadly")

[0] https://lore.kernel.org/all/20250409-page-pool-track-dma-v9-0-6a9ef2e0cba8@redhat.com/

Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-01-27 12:21:20 +01:00
Heiko Carstens
e5f3e67de5 s390: Add CC_HAS_ASM_IMMEDIATE_STRINGS
Upcoming changes to s390 specific inline assemblies require the usage of
strings as immediate input operands. This works only with gcc-9 and newer
compilers. With gcc-8 this leads to a compile error:

void bar(void) { asm volatile("" :: "i" ("foo")); }

Results in:

In function 'bar':
 warning: asm operand 0 probably doesn't match constraints
  asm volatile("" :: "i" ("foo"));
  ^~~
 error: impossible constraint in 'asm'

Provide a CC_HAS_ASM_IMMEDIATE_STRINGS config option which allows to tell
if the compiler supports strings as immediate input operands.
Based on that conditional code can be provided.

Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-01-27 12:16:15 +01:00
Thomas Weißschuh
eb2606bba1 s390: Implement ARCH_HAS_CC_CAN_LINK
The generic CC_CAN_LINK detection relies on -m32/-m64 compiler flags.
Some s390 toolchains use -m31 instead but that is not supported in the
kernel.

Make the logic easier to understand and allow the simplification of the
generic CC_CAN_LINK by using a tailored implementation.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-12-23 11:46:35 +01:00
Tobias Schumacher
f770950a47 s390/pci: Migrate s390 IRQ logic to IRQ domain API
s390 is one of the last architectures using the legacy API for setup and
teardown of PCI MSI IRQs. Migrate the s390 IRQ allocation and teardown
to the MSI parent domain API. For details, see:

https://lore.kernel.org/lkml/20221111120501.026511281@linutronix.de

In detail, create an MSI parent domain for each PCI domain. When a PCI
device sets up MSI or MSI-X IRQs, the library creates a per-device IRQ
domain for this device, which is used by the device for allocating and
freeing IRQs.

The per-device domain delegates this allocation and freeing to the
parent-domain. In the end, the corresponding callbacks of the parent
domain are responsible for allocating and freeing the IRQs.

The allocation is split into two parts:
- zpci_msi_prepare() is called once for each device and allocates the
  required resources. On s390, each PCI function has its own airq
  vector and a summary bit, which must be configured once per function.
  This is done in prepare().
- zpci_msi_alloc() can be called multiple times for allocating one or
  more MSI/MSI-X IRQs. This creates a mapping between the virtual IRQ
  number in the kernel and the hardware IRQ number.

Freeing is split into two counterparts:
- zpci_msi_free() reverts the effects of zpci_msi_alloc() and
- zpci_msi_teardown() reverts the effects of zpci_msi_prepare(). This is
  called once when all IRQs are freed before a device is removed.

Since the parent domain in the end allocates the IRQs, the hwirq
encoding must be unambiguous for all IRQs of all devices. This is
achieved by encoding the hwirq using the devfn and the MSI index.

Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Tobias Schumacher <ts@linux.ibm.com>
Reviewed-by: Gerd Bayer <gbayer@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-12-07 16:15:23 +01:00
Heiko Carstens
eb9780a1a3 s390: Select POSIX_CPU_TIMERS_TASK_WORK
After support for VIRT_XFER_TO_GUEST_WORK is available for s390 it is
possible to also select HAVE_POSIX_CPU_TIMERS_TASK_WORK. See [1] for the
reasons why it makes sense, also for architectures which do not support
PREEMPT_RT.

[1] https://lore.kernel.org/all/20200716201923.228696399@linutronix.de

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-12-07 16:15:19 +01:00
Linus Torvalds
2547f79b0b s390 updates for 6.19 merge window
- Provide a new interface for dynamic configuration and deconfiguration of
   hotplug memory, allowing with and without memmap_on_memory support. This
   makes the way memory hotplug is handled on s390 much more similar to
   other architectures
 
 - Remove compat support. There shouldn't be any compat user space around
   anymore, therefore get rid of a lot of code which also doesn't need to be
   tested anymore
 
 - Add stackprotector support. GCC 16 will get new compiler options, which
   allow to generate code required for kernel stackprotector support
 
 - Merge pai_crypto and pai_ext PMU drivers into a new driver. This removes
   a lot of duplicated code. The new driver is also extendable and allows
   to support new PMUs
 
 - Add driver override support for AP queues
 
 - Rework and extend zcrypt and AP trace events to allow for tracing of
   crypto requests
 
 - Support block sizes larger than 65535 bytes for CCW tape devices
 
 - Since the rework of the virtual kernel address space the module area and
   the kernel image are within the same 4GB area. This eliminates the need
   of weak per cpu variables. Get rid of ARCH_MODULE_NEEDS_WEAK_PER_CPU
 
 - Various other small improvements and fixes
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEECMNfWEw3SLnmiLkZIg7DeRspbsIFAmktZioACgkQIg7DeRsp
 bsK4Rw//VzkvHyzOtGKZ8Hb4S+Sh/PFlaZQXNhj+Xt5gWoOhP1uPmmhBe6LxjYaB
 J9Ns3hpONQ1dTHV7VVkds8FvM/SBcGe8m5RpefmChC/bjm5UEOV/MppKtA0aLnEH
 hJmdubIrrRAXKggxlHEfRLzBsFvV/rJ9Xf16FhRxGDc4pgmgkI1NPQ41/dyCHklQ
 dB3YrFVPIETywVYYVB/G3h11JgF5Z6CKtjYCdSx72Fkbj65+6JPfcPgLKMpcJuPd
 UxUXtCo1FCXlP70jsz8JQI8cdieG0KDQTtnZP4P/pqjQ3wirOqvMewNa9t9xmQ2e
 p6Rc1Vx5DESkq9bRWtQEaprTVVzK7DDLH3RuZwB+uLrcLGD8JvVS6/m9n9CgzBMT
 BnJXG2sLZH+gdQy+DSD/fVDD7OvIk8TGrH+OFwVIKhrT/J3B2E7ZSYyZZCNIS7VG
 yiuypoDGYg3ZpYjH9+qOXWB3nc0vQWrlFzb1bsQu1omJGmunLv4jtTjAKGN82C33
 auBsIYAlQW20X7DV0vZa59PwqwtBqtdQQcTidwtSztzKogRXAdK8KKHtN60JM4S2
 7sWFOFCQaTChAeDNw6MF5EtULb551nwH2RtJ9x3CrJj+OGK6clbQNcxIA7Oy0veR
 Sl9v1lMfeKOgDrPdDy3ArQBJ8WLlF9qX9wLKbiaNyIKmkz2ymkg=
 =CNrb
 -----END PGP SIGNATURE-----

Merge tag 's390-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Heiko Carstens:

 - Provide a new interface for dynamic configuration and deconfiguration
   of hotplug memory, allowing with and without memmap_on_memory
   support. This makes the way memory hotplug is handled on s390 much
   more similar to other architectures

 - Remove compat support. There shouldn't be any compat user space
   around anymore, therefore get rid of a lot of code which also doesn't
   need to be tested anymore

 - Add stackprotector support. GCC 16 will get new compiler options,
   which allow to generate code required for kernel stackprotector
   support

 - Merge pai_crypto and pai_ext PMU drivers into a new driver. This
   removes a lot of duplicated code. The new driver is also extendable
   and allows to support new PMUs

 - Add driver override support for AP queues

 - Rework and extend zcrypt and AP trace events to allow for tracing of
   crypto requests

 - Support block sizes larger than 65535 bytes for CCW tape devices

 - Since the rework of the virtual kernel address space the module area
   and the kernel image are within the same 4GB area. This eliminates
   the need of weak per cpu variables. Get rid of
   ARCH_MODULE_NEEDS_WEAK_PER_CPU

 - Various other small improvements and fixes

* tag 's390-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (92 commits)
  watchdog: diag288_wdt: Remove KMSG_COMPONENT macro
  s390/entry: Use lay instead of aghik
  s390/vdso: Get rid of -m64 flag handling
  s390/vdso: Rename vdso64 to vdso
  s390: Rename head64.S to head.S
  s390/vdso: Use common STABS_DEBUG and DWARF_DEBUG macros
  s390: Add stackprotector support
  s390/modules: Simplify module_finalize() slightly
  s390: Remove KMSG_COMPONENT macro
  s390/percpu: Get rid of ARCH_MODULE_NEEDS_WEAK_PER_CPU
  s390/ap: Restrict driver_override versus apmask and aqmask use
  s390/ap: Rename mutex ap_perms_mutex to ap_attr_mutex
  s390/ap: Support driver_override for AP queue devices
  s390/ap: Use all-bits-one apmask/aqmask for vfio in_use() checks
  s390/debug: Update description of resize operation
  s390/syscalls: Switch to generic system call table generation
  s390/syscalls: Remove system call table pointer from thread_struct
  s390/uapi: Remove 31 bit support from uapi header files
  s390: Remove compat support
  tools: Remove s390 compat support
  ...
2025-12-02 16:37:00 -08:00
Heiko Carstens
f5730d44e0 s390: Add stackprotector support
Stackprotector support was previously unavailable on s390 because by
default compilers generate code which is not suitable for the kernel:
the canary value is accessed via thread local storage, where the address
of thread local storage is within access registers 0 and 1.

Using those registers also for the kernel would come with a significant
performance impact and more complicated kernel entry/exit code, since
access registers contents would have to be exchanged on every kernel entry
and exit.

With the upcoming gcc 16 release new compiler options will become available
which allow to generate code suitable for the kernel. [1]

Compiler option -mstack-protector-guard=global instructs gcc to generate
stackprotector code that refers to a global stackprotector canary value via
symbol __stack_chk_guard. Access to this value is guaranteed to occur via
larl and lgrl instructions.

Furthermore, compiler option -mstack-protector-guard-record generates a
section containing all code addresses that reference the canary value.

To allow for per task canary values the instructions which load the address
of __stack_chk_guard are patched so they access a lowcore field instead: a
per task canary value is available within the task_struct of each task, and
is written to the per-cpu lowcore location on each context switch.

Also add sanity checks and debugging option to be consistent with other
kernel code patching mechanisms.

Full debugging output can be enabled with the following kernel command line
options:

debug_stackprotector
bootdebug
ignore_loglevel
earlyprintk
dyndbg="file stackprotector.c +p"

Example debug output:

stackprot: 0000021e402d4eda: c010005a9ae3 -> c01f00070240

where "<insn address>: <old insn> -> <new insn>".

[1] gcc commit 0cd1f03939d5 ("s390: Support global stack protector")

Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-11-24 11:45:21 +01:00
Heiko Carstens
e950d1f84d s390/percpu: Get rid of ARCH_MODULE_NEEDS_WEAK_PER_CPU
Since the rework of the kernel virtual address space [1] the module area
and the kernel image are within the same 4GB area. Therefore there is no
need for the weak per cpu workaround for modules anymore. Remove it.

[1] commit c98d2ecae0 ("s390/mm: Uncouple physical vs virtual address spaces")

Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-11-24 11:45:20 +01:00
Heiko Carstens
8e0b986c59 s390: Remove compat support
There shouldn't be any 31 bit code around anymore that matters.
Remove the compat layer support required to run 31 bit code.

Reason for removal is code simplification and reduced test effort.

Note that this comes without any deprecation warnings added to config
options, or kernel messages, since most likely those would be ignored
anyway.

If it turns out there is still a reason to keep the compat layer this
can be reverted at any time in the future.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-11-17 11:10:38 +01:00
Heiko Carstens
64e2f60f35 s390: Disable ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
As reported by Luiz Capitulino enabling HVO on s390 leads to reproducible
crashes. The problem is that kernel page tables are modified without
flushing corresponding TLB entries.

Even if it looks like the empty flush_tlb_all() implementation on s390 is
the problem, it is actually a different problem: on s390 it is not allowed
to replace an active/valid page table entry with another valid page table
entry without the detour over an invalid entry. A direct replacement may
lead to random crashes and/or data corruption.

In order to invalidate an entry special instructions have to be used
(e.g. ipte or idte). Alternatively there are also special instructions
available which allow to replace a valid entry with a different valid
entry (e.g. crdte or cspg).

Given that the HVO code currently does not provide the hooks to allow for
an implementation which is compliant with the s390 architecture
requirements, disable ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP again, which is
basically a revert of the original patch which enabled it.

Reported-by: Luiz Capitulino <luizcap@redhat.com>
Closes: https://lore.kernel.org/all/20251028153930.37107-1-luizcap@redhat.com/
Fixes: 00a34d5a99 ("s390: select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP")
Cc: stable@vger.kernel.org
Tested-by: Luiz Capitulino <luizcap@redhat.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-10-30 16:59:28 +01:00
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.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaN3cywAKCRDdBJ7gKXxA
 jtaPAQDmIuIu7+XnVUK5V11hsQ/5QtsUeLHV3OsAn4yW5/3dEQD/UddRU08ePN+1
 2VRB0EwkLAdfMWW7TfiNZ+yhuoiL/AA=
 =4mhY
 -----END PGP SIGNATURE-----

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
4b81e2eb9e Updates for the VDSO subsystem:
- Further consolidation of the VDSO infrastructure and the common data
     store.
 
   - Simplification of the related Kconfig logic
 
   - Improve the VDSO selftest suite
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmjaUJgTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoT5VD/9l+TP42vJzwygPArefVM9QijAc4k+g
 iptaz5M+Lhk0BlwMUu502Tp1zcwGq5529LlE2P72DuYoZRtZKSFCGES2mye0JiAs
 A5Vk8d1zicg3IIGjYgw39shA9ghzuzV3gZdgHVqQ6024uSeKxUY3SqF156GGfPFG
 azXWDV7i4RGQvKLm2ye8m7JNYCE3P9f8Wh+GvPaq7qBlW1MsMCWC4FP5qu4iStf3
 mol9uA/EM2zSDwkpIpq6P5L2TpIH1dGDNGxVf/HG3J16UhNXzzXv/rxuKHKPNGWm
 MQZ8WdPjF+uwdUsNXaImC6aCE0hoQ1Ga7GE2YA3pMQYfySeiJ/fA5I1KfhlUCiHD
 oUgnb6PQfZjaBDrIODKcrFHAYc5pTOyJXnJ6q1Lc1yrOfoVcIpMaRXHO/phCeuwI
 61gfb9ggbFEH/7cL26Z9XGSqh4BDCKVP5Z+y98OnNEzV74ScpX13/szB3VgdN6LW
 tmTOeMPYCo4FQoPw8OV1xkeYOKD2JyqH+garnxDZNFjaVaeUkzlAMKz+1JUjxRZj
 UpUhZ8y5KFVjgKkqZHxhucr9cnwV/xd4n+IzZeG4l6XZp4VyirG+5QpAikGYe+Jq
 WFU4Ao1xvevyizrJEhoGJKznwtrNrsy6AQ+wLQxYiRR4aTnng8n9T/ry2DVvhJf8
 diYWxuRTR7KMxg==
 =i3UB
 -----END PGP SIGNATURE-----

Merge tag 'timers-vdso-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull VDSO updates from Thomas Gleixner:

 - Further consolidation of the VDSO infrastructure and the common data
   store

 - Simplification of the related Kconfig logic

 - Improve the VDSO selftest suite

* tag 'timers-vdso-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  selftests: vDSO: Drop vdso_test_clock_getres
  selftests: vDSO: vdso_test_abi: Add tests for clock_gettime64()
  selftests: vDSO: vdso_test_abi: Test CPUTIME clocks
  selftests: vDSO: vdso_test_abi: Use explicit indices for name array
  selftests: vDSO: vdso_test_abi: Drop clock availability tests
  selftests: vDSO: vdso_test_abi: Use ksft_finished()
  selftests: vDSO: vdso_test_abi: Correctly skip whole test with missing vDSO
  selftests: vDSO: Fix -Wunitialized in powerpc VDSO_CALL() wrapper
  vdso: Add struct __kernel_old_timeval forward declaration to gettime.h
  vdso: Gate VDSO_GETRANDOM behind HAVE_GENERIC_VDSO
  vdso: Drop Kconfig GENERIC_VDSO_TIME_NS
  vdso: Drop Kconfig GENERIC_VDSO_DATA_STORE
  vdso: Drop kconfig GENERIC_COMPAT_VDSO
  vdso: Drop kconfig GENERIC_VDSO_32
  riscv: vdso: Untangle Kconfig logic
  time: Build generic update_vsyscall() only with generic time vDSO
  vdso/gettimeofday: Remove !CONFIG_TIME_NS stubs
  vdso: Move ENABLE_COMPAT_VDSO from core to arm64
  ARM: VDSO: Remove cntvct_ok global variable
  vdso/datastore: Gate time data behind CONFIG_GENERIC_GETTIMEOFDAY
2025-09-30 16:58:21 -07:00
Linus Torvalds
7601d18be0 A set of changes to consolidate the generic TIF bits accross architectures
All architectures define the same set of generic TIF bits. This makes it
 pointlessly hard to add a new generic TIF bit or to change an existing one.
 
 Provide a generic variant and convert the architectures which utilize the
 generic entry code over to use it. The TIF space is divided into 16 generic
 bits and 16 architecture specific bits, which turned out to provide enough
 space on both sides.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmjaP78THHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoTKyD/9NEg3DiN6aM959o1MhvhDk7jNdECXm
 QOvZ85wJYhCv3Pb7RSgMxJL/dR9aWV2b24TSzEeki0awbR4nPeUz82vExmgS7rWX
 9rQLPrOZsrYd76IcAVoV5Ua/g48c+9TM8kLzoZFa9JEYMPmyTEiA3gy4bgab/aov
 L2b903ZrCNkWRKM1Wz5V8xdyPEzhE+cLhbWoPbeCqfzxqbv4+WWKQlPmqamQw+yq
 /61Xhq0tmx3+4hn1IB/Rc8yMTbAK0EwN7SHM+l7yaJ3ijlkGSele4S3mKAHv2I3c
 vODIFwdQ8pRbC1C5eMBnUKRm7Cmf+8CB3m+OIA5ghj10TPFiTUzQ6iG6nUSVniJm
 QB21LHYSWroeQBRibnT5k7RiW5QjtTQmcsjvO7S2rZ/7CkMr7LMu6kN1P0TSiOvc
 SKxs3MO72KaRU/JrEjLqvT2tvdpg2hpffg69U0jA1xCeFULE1jrqo3GwL8dPDk7z
 zKbC73JNg4QJDdi+hIn5nl0fRGVszLzkDum5eyCpCLY/W7BSiQ7q/ayzt9upsSOm
 uc7sqeIgelQMRDMoMNcQUsMnApT0JHOS74WQ03SfahZESj8eFoOb8pr7vaqu4lfi
 6LV4fpwZPBTMDcQ36r2JLuUTqHNHNtWn4xXjQ72ngovIVUL9A2H0DqK+1JhLJ6yX
 tknZ9WVmWVf+JQ==
 =6L98
 -----END PGP SIGNATURE-----

Merge tag 'core-core-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull TIF bit unification updates from Thomas Gleixner:
 "A set of changes to consolidate the generic TIF (thread info flag)
  bits accross architectures.

  All architectures define the same set of generic TIF bits. This makes
  it pointlessly hard to add a new generic TIF bit or to change an
  existing one.

  Provide a generic variant and convert the architectures which utilize
  the generic entry code over to use it. The TIF space is divided into
  16 generic bits and 16 architecture specific bits, which turned out to
  provide enough space on both sides"

* tag 'core-core-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  LoongArch: Fix bitflag conflict for TIF_FIXADE
  riscv: Use generic TIF bits
  loongarch: Use generic TIF bits
  s390/entry: Remove unused TIF flags
  s390: Use generic TIF bits
  x86: Use generic TIF bits
  asm-generic: Provide generic TIF infrastructure
2025-09-30 14:36:20 -07:00