Commit Graph

1015 Commits

Author SHA1 Message Date
Linus Torvalds
0c8bf38058 vfs-7.4-rc1.fixes
Please consider pulling these changes from the signed vfs-7.4-rc1.fixes tag.
 
 Thanks!
 Christian
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCauTJqQAKCRCRxhvAZXjc
 okLyAP0bHWHQ8CIbegVzZbMVssaMJl1KiqxfkGbS6Nk/j1StkwEA5+UGbFnQ2qG6
 uxDILfnlsd834jlOlOauzaSpbAJgwQk=
 =uPnP
 -----END PGP SIGNATURE-----

Merge tag 'vfs-7.4-rc1.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs fixes from Christian Brauner:

 - writeback:

    - Update dirtied_when instead of dirtied_time_when when a wb switch
      puts an inode at the newest end of the target b_dirty list. The
      list was left out of order so move_expired_inodes() could stop
      before older inodes, and the lazytime expiration timestamp was
      reset

    - Clear the old wb's dirty-I/O state and bandwidth contribution when
      a batch of inode switches leaves its dirty lists empty. An empty
      wb stayed scheduled for periodic writeback and inflated
      bdi->tot_write_bandwidth

    - Take wb_switch_rwsem across the inode scan of
      cleanup_offline_cgwb(). The v7.3-rc5 fix that rotates scanned
      inodes let a scan racing a sync()'s queue_io() move lazytime
      inodes past the sync's cutoff, so sync() returned without
      persisting their timestamps

    - Don't kick writeback for an IOCB_DONTCACHE write on an inode that
      has no wb yet. With cgroup writeback an O_DIRECT RWF_DONTCACHE
      write to a block device dereferenced NULL

 - statmount/listmount/listns:

    - Refuse statmount() string requests with a buffer that isn't larger
      than struct statmount

    - Don't wrap around with a U64_MAX cursor in listmount() and
      listns()

    - Don't end listns() at an inactive namespace

    - Only add init_ipc_ns and init_net to the namespace trees if
      CONFIG_IPC_NS and CONFIG_NET_NS are enabled

 - iomap:

    - Only mark blocks uptodate in __iomap_write_begin() after reading
      them and let __iomap_write_end() mark the zeroed blocks uptodate
      once the copy from userspace succeeded

    - Check a chunk against max_integrity_io_size() on its own before
      the bio size check

    - Only enforce block alignment for direct I/O into holes and
      unwritten extents if IOMAP_DIO_FSBLOCK_ALIGNED is set

 - backing-file:

    - Check S_APPEND and S_IMMUTABLE on the backing inode. FUSE
      passthrough opens the backing file with vfs_open() which skips
      may_open(), so anyone who may open the FUSE file for writing could
      overwrite an append-only backing file anywhere or write to an
      immutable one. Open, mmap and writes now check the backing inode
      the way may_open() and do_mmap() do

    - Always call kiocb_end_write() for a queued write

    - Let backing files inherit FMODE_NONOTIFY from the user file. The
      event fds fanotify creates for permission events on a stacked
      filesystem raised FS_OPEN_PERM on the real path from inside the
      listener's read() and deadlocked listeners with marks on both
      layers

 - pidfs:

    - Look the task up before checking for exit information in
      PIDFD_GET_INFO and start over if the task no longer owns the pid
      once all fields have been read. A caller racing release_task() got
      neither PIDFD_INFO_PID nor PIDFD_INFO_EXIT or ESRCH although the
      exit information was available, and a caller racing a sub-thread's
      exec reported that thread's tid as the pid

    - Clear the mask bits of fields that lie beyond the struct size the
      caller passed. The uapi header promises that the mask names no
      such field but a caller passing PIDFD_INFO_SIZE_VER0 got the
      coredump and supported mask bits set for fields that were never
      written

 - aio:

    - Give the aio ring a ->read_folio that fails with EIO so a fault on
      a ring whose file was truncated gets SIGBUS instead of jumping to
      NULL

    - Check nr_events against the ring size before doubling it in
      ioctx_alloc()

 - splice:

    - Only write back an implicit file position in do_splice() when the
      splice helper succeeded. splice doesn't take f_pos_lock so a
      failed splice restored a stale snapshot over a position that a
      concurrent getdents() had moved. On ext2 the next readdir then
      trusted an offset inside a directory entry

    - Retry tee() when the input pipe was emptied or the output pipe
      filled between the prep steps and link_pipe() instead of returning
      0 while the input pipe still has writers, as splice_pipe_to_pipe()
      does

 - ucount:

    - Take the reference that pins a ucounts level on the 0 -> 1
      transition before checking the rlimit

    - Read the parent ucounts before dropping the rlimit count in
      do_dec_rlimit_put_ucounts()

 - inode:

    - Rotate inodes whose page cache couldn't be dropped to the tail of
      the LRU

    - Skip inodes that another LRU walker is isolating

 - setns:

    - Set nsset->flags before anything in prepare_nsset() can fail so
      the error path drops the cred prepared for CLONE_NEWUSER. A
      failing setns() with CLONE_NEWUSER and CLONE_NEWNS leaked it
      together with its user namespace

    - Refuse setns(CLONE_NEWNS) for a task that shares its fs_struct
      again when more namespaces are requested

 - minix:

    - Restore uptodate on the pinned bitmap buffers before redirtying
      them after a failed writeback instead of tripping the warning in
      mark_buffer_dirty(), as ext2 and ext4 do for their superblock
      buffers

    - Reject rmdir() of a directory with a corrupted link count with
      EFSCORRUPTED instead of hitting the drop_nlink() warning

 - userns: Keep the exec securebits and their locks when creating or
   joining a user namespace. set_cred_user_ns() reset all securebits to
   SECUREBITS_DEFAULT so anyone who may create a user namespace could
   shed SECBIT_EXEC_RESTRICT_FILE and SECBIT_EXEC_DENY_INTERACTIVE with
   a single unshare(CLONE_NEWUSER)

 - fs: Honor FOP_UNSIGNED_OFFSET in sys_llseek() and in the pread64(),
   pwrite64(), preadv() and pwritev() wrappers

 - proc/kcore: Advance the vmalloc retry in read_kcore_iter() by the
   last vread_iter() copy instead of the running total

 - eventpoll: Return the error when the wakeup source for EPOLLWAKEUP
   can't be created in EPOLL_CTL_MOD instead of reporting success
   without suspend protection

 - coredump: Mark do_coredump() noinline_for_stack

 - nsfs: Check the trailing bytes of a namespace file handle in bytes
   instead of words

 - netfs: Restore the per-level and per-point decoding of the debug mask

 - exportfs: Release the directory file get_name() opened with
   __fput_sync(). From nfsd's kernel threads the deferred fputs arrived
   faster than delayed_fput retired them and each pinned the directory's
   readdir state, growing unreclaimable slab by about 90 MB per second
   under a parallel tree walk

 - fs: Call ramfs_kill_sb() for a ramfs rootfs. Since rootfs can be
   unmounted as of v7.0 its struct ramfs_fs_info was leaked

 - signal: Check the blocked mask for every entry
   dequeue_synchronous_signal() looks at. The scan could select a
   blocked synchronous signal and deliver it while blocked

 - super: Convert the superblock device table from an rhltable to a
   plain hashtable under a spinlock. This fixes a bug from v7.3 where
   fs_bdev_freeze() froze a btrfs filesystem through a stale member that
   open_ctree() had already released while the freeze was waiting for
   SB_BORN

 - fork: Leave rcu_users at zero until copy_process() can't fail
   anymore. bpf_task_acquire() handed out trusted references to the new
   task from the task_alloc LSM hook and sched_ext's ops.init_task() and
   a failing fork freed the task behind them

 - xattr: Always run cap_convert_nscap() for a security.capability
   write. A zero-length setxattr() skipped it and let an unprivileged
   caller without CAP_SETFCAP or write permission on the file plant an
   empty security.capability xattr that made every execve() of the
   binary fail with EINVAL

 - namei: Skip the S_ISDIR assertion in

 - proc: Refuse to mount on entries below /proc/<pid>/net like fd/,
   fdinfo/ and map_files/. proc_net_d_revalidate() always fails so the
   first lookup by anyone with search permission ran d_invalidate() on
   the dentry and detached every mount on it, locked mounts included

 - libfs: Hold one mount reference for all pins instead of one per pin.
   The pin count is what keeps the mount alive, so the per-pin reference
   only cost a mntget() and a mntput() through
   mntput_no_expire_slowpath() for every debugfs, tracefs, securityfs or
   configfs file that comes and goes

 - iov_iter: Return 0 from iov_iter_alignment() for an empty iterator of
   any type

 - watch_queue: Give info_id its own storage instead of overlaying it
   with rcu_head

 - filelock: Take an active superblock reference while waiting for a
   delegation break. After a lazy umount closing the delegation holder
   could shut down the superblock under the waiter whose final iput()
   then ran shmem_evict_inode() on freed state

 - fs: Skip the copy_file_range() write limit checks when there is no
   data to copy

 - bpf: Allow bpf_d_path() from fentry on filp_close_sync(). Since
   close_range() became synchronous this cycle close(), close_range()
   and the closes on exec and exit no longer go through filp_close().
   fexit stays rejected since the file may be gone by then

 - fs_pin: Dequeue the wait entry unconditionally in pin_kill(). A
   spuriously woken waiter kept its on-stack entry queued, took that as
   proof that the pin was alive and used the freed acct structure when
   umount() of the accounting file raced acct(2)

 - dcache: Don't fail __d_obtain_alias() for an inode without links and
   aliases. The ESTALE check added this cycle broke open_by_handle_at()
   and nfsd file handle decoding on NFS and FUSE where i_nlink is just
   what the server last reported and the handle may well still be valid

 - selftests/ovl: Fix the mountinfo expectations of the detached layer
   test which has failed since it was added

* tag 'vfs-7.4-rc1.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (60 commits)
  fs: don't fail __d_obtain_alias() for unlinked inodes
  ns: don't add init_ipc_ns and init_net without namespace support
  aio: avoid request count overflow in ioctx_alloc()
  selftests/ovl: fix detached layer mountinfo expectations
  bpf: Allow bpf_d_path() from filp_close_sync()
  fs: skip copy_file_range write limits when there is no data
  minix: reject rmdir of a directory with a corrupted link count
  fs_pin: do not trust the pin after a spurious wakeup in pin_kill()
  ucount: read the parent ucounts before dropping the rlimit count
  splice: retry tee() instead of returning 0 when it races
  selftests/pidfd: test that fields beyond the struct size are not reported
  pidfs: do not report fields that do not fit into the caller's struct
  fs: let backing files inherit FMODE_NONOTIFY from the user file
  splice: avoid stale f_pos writeback on error
  backing-file: always end a queued write
  filelock: keep superblock active through delegation wait
  watch_queue: keep info_id separate from rcu_head
  iomap: only follow dio alignment requirement if specified
  iov_iter: fix NULL deref in iov_iter_alignment()
  backing-file: enforce append-only and immutable backing inodes
  ...
2026-10-30 09:25:01 -10:00
Christian Brauner
82f1c815aa
ns: don't add init_ipc_ns and init_net without namespace support
When CONFIG_IPC_NS or CONFIG_NET_NS are turned off we still add the
initial ipc and network namespace to the namespace trees. ipc_ns_init()
calls ns_tree_add(&init_ipc_ns) whenever CONFIG_SYSVIPC is set and
setup_net() calls ns_tree_add_raw() on init_net whenever CONFIG_NET is
set.

But without CONFIG_IPC_NS and CONFIG_NET_NS these aren't namespaces
userspace can do anything with. They don't have proc_ns_operations so
there's no /proc/<pid>/ns/{ipc,net} for them, nsfs_fh_to_dentry()
refuses them with -EOPNOTSUPP, and since ns->ops is NULL
__ns_tree_add_raw() doesn't add them to the owner list of init_user_ns
either. So they end up half registered. That's also not how we treat
any of the other namespace types. Without CONFIG_UTS_NS, CONFIG_PID_NS,
CONFIG_TIME_NS or CONFIG_USER_NS the initial namespace is never added
to the tree.

listns() walks the unified tree and calls is_current_namespace() for
every namespace it finds via may_list_ns(). But is_current_namespace()
only knows about CLONE_NEWIPC and CLONE_NEWNET if CONFIG_IPC_NS and
CONFIG_NET_NS are set. Otherwise we end up in the default case and its
VFS_WARN_ON_ONCE(). Any unprivileged caller can trigger that with a
plain listns() call:

  WARNING: CPU: 0 PID: 526 at fs/nsfs.c:508 is_current_namespace+0x12f/0x440
  Call Trace:
   legitimize_ns+0x25f/0x4c0
   do_listns+0x185/0x5c0
   __do_sys_listns+0x13b/0x300

Instead of teaching is_current_namespace() about namespaces that can't
be opened, only add the initial namespaces to the tree if their
namespace type is enabled. Move the registration of init_ipc_ns into
ipc/namespace.c which is only built with CONFIG_IPC_NS. That also fixes
CONFIG_SYSVIPC=n, CONFIG_POSIX_MQUEUE=y, CONFIG_IPC_NS=y where
ipc/shm.c isn't built and init_ipc_ns was never added at all. For the
network namespace only call ns_tree_add_raw() if CONFIG_NET_NS is set.
Without CONFIG_NET_NS cleanup_net() isn't built and init_net is never
removed so there's nothing to balance.

Fixes: 74b24a582e ("ipc: support ns lookup")
Fixes: 195f742229 ("net: support ns lookup")
Reported-by: kernel test robot <yi1.lai@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202610260917.6248e316-lkp@intel.com
Cc: stable@vger.kernel.org # v6.18+
Link: https://patch.msgid.link/20261030-work-nsfs-init_ns_tree-v1-1-7ec0adb47c54@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-10-30 17:17:55 +01:00
Linus Torvalds
8a36f53fd5 mm.git review status for linus..mm-stable
Everything:
 
 Total patches:       213
 Fixes: tags:         69
 cc:stable patches:   43
 Reviews/patch:       2.04
 Reviewed rate:       86%
 
 Excluding DAMON:
 
 Total patches:       192
 Fixes: tags:         63
 cc:stable patches:   39
 Reviews/patch:       2.18
 Reviewed rate:       89%
 
 Excluding DAMON and selftests:
 
 Total patches:       182
 Fixes: tags:         57
 cc:stable patches:   39
 Reviews/patch:       2.23
 Reviewed rate:       89%
 
 Summary of series in this merge:
 
 - "mm: make VMA flag semantics explicit, eliminate VM_SPECIAL"
   (Lorenzo Stoakes (ARM)):
 
   Replace VM_SPECIAL with helpers describing mapping ownership and
   behavior.  Enforce the mmap flag rules and convert affected drivers,
   removing ambiguous tests shared by driver mappings and ordinary memory.
 
 - "support kselftest on nommu platform" (Hajime Tazaki):
 
   Add opt-in mmap and mremap tests for NOMMU systems.  Teach the runner to
   avoid its fork-dependent timeout command and document the build and
   runtime requirements.
 
 - "mm/collapse: separate a collapse from its callers"
   (Kiryl Shutsemau (Meta)):
 
   Separate huge-page collapse from caller policy.  Replace khugepaged
   identity checks with explicit permissions, and separate scanning from
   collapse with the mmap_lock drop in one place.
 
 - "mm: implement and use vma_has_anon_rmap(), silence KCSAN"
   (Lorenzo Stoakes (ARM)):
 
   Provide a common helper for testing whether a VMA has anonymous reverse
   mappings.  Document the locking rules, annotate intentional concurrent
   reads for KCSAN, and convert the core MM callers.
 
 - "mm/sparse: remove SECTION_MARKED_PRESENT and further cleanups"
   (David Hildenbrand (Arm)):
 
   Remove SECTION_MARKED_PRESENT in favor of the early-section flag.
   Simplify sparse memory initialization, section metadata handling and
   related PFN validity checks.
 
 - "sh: remove NUMA and SPARSEMEM support" (Mike Rapoport (Microsoft)):
 
   Remove SuperH NUMA and SPARSEMEM support.  The extra memory banks have
   been unusable since the NO_BOOTMEM conversion, leaving only the code and
   data overhead.
 
 - "mm: Unify device DAX and HugeTLB vmemmap population paths"
   (Muchun Song):
 
   Unify the generic device DAX and HugeTLB vmemmap population paths and
   shared tail-page handling.  Remove the duplicate DAX machinery while
   retaining the powerpc radix implementation.
 
 - "kselftest: mm: fix some failure of split_huge_page_test" (Yeoreum Yun):
 
   Fix huge-page split tests racing with khugepaged recollapse.  Use pagemap
   and page flags instead of VMA-boundary assumptions which fail when glibc
   has already enabled THP.
 
 - "memcg: move memcgid refcount to objcg to unpin dying memcgs"
   (Bingfang Guo):
 
   Let dying memcgs be freed while swapped-out shmem still holds their IDs.
   Move ID references to reparentable objcgs, with the necessary swap
   accounting and RCU lifetime changes.
 
 - "mm/truncate: fix data loss when truncating straddling large folios"
   (Zhang Yi):
 
   Preserve out-of-range data when truncating straddling large folios.  Fix
   a lookup race and split-failure handling, and handle minimum folio orders
   for the forthcoming ext4 iomap buffered I/O path.
 
 - "mm/damon: introduce damos quota goal target metric complement flag"
   (SJ Park):
 
   Let DAMOS quota goals use a metric's complement, so utilization can also
   express free-memory goals without adding separate metrics.  Add the sysfs
   interface, documentation and tests.
 
 - "arm64/mm: Standardize printing for pgtable entries" (Anshuman Khandual):
 
   Use the generic formatter for arm64 page-table entries, ready for future
   wider entries.  Move the safe-PTE-update check out of the header to avoid
   an include cycle.
 
 - "mm: kmsan: fix iounmap metadata teardown" (Dima Koziuk):
 
   Fix KMSAN metadata leaks on iounmap and failed ioremap allocations.  Free
   backing pages before removing their mappings, and share the teardown with
   partial-allocation cleanup.
 
 - "mm/damon/core: preserve quota state when constructing schemes"
   (Karl Mehltretter):
 
   Preserve running DAMOS quota state while validating parameter updates.
   Even rejected updates could reset accounting and exceed the quota window;
   add tests for both accepted and rejected updates.
 
 - "mm/vmalloc: fix vmalloc_dump_obj VA lookup" (Ye Liu):
 
   Fix vmalloc_dump_obj() lookups for last-page addresses and allocations
   spanning vmap zones.  These allocations were being missed in diagnostic
   output.
 
 - "mm: various (urgent?) fixes" (David Hildenbrand (Arm)):
 
   Fix mmap charge leaks and hugetlb use-after-free, wrong-address
   unmapping, stuck locks and endless faults.  Also preserve reservations on
   failed mremap and handle stale userfaultfd bits.
 
 - "maple_tree: fix maple_range_64 crashes in RCU mode" (Dimitris Charisis):
 
   Fix pointer and metadata confusion during RCU destruction of
   maple_range_64 nodes, avoiding double frees and invalid accesses.  Add a
   regression test; no in-tree user currently uses this combination.
 
 - "mm: fix hugetlb NR_HUGETLB accounting on folio migration" (Hongfu Li):
 
   Fix hugetlb migration and preallocation accounting so /proc/vmstat
   retains the correct count and memory.numa_stat follows the folio to its
   new node.
 
 - "mm/damon: fix a minor bug, clean code, and add a test" (SJ Park):
 
   Fix 32-bit DAMON age overflow which made old regions look young.  Share
   hugetlb folio acquisition code and add a regression test for the
   previously fixed last-region skipping bug.
 
 - "mm/damon/core: cleanup code, reduce stack usage, and add kunit"
   (SJ Park):
 
   Reduce kdamond stack usage and remove unused enums.  Add deterministic
   PSI quota-goal tests which do not depend on the machine's current memory
   pressure.
 
 - "mm/damon: fix the temporal goal tuner's size quota conversion"
   (Donggeun Yoo):
 
   Bound the temporal tuner's quota conversion to prevent overflow and zero
   effective quotas, which could stop schemes making progress.  Add boundary
   tests.
 
 - "Don't use GFP_DMA when calling dma_alloc_coherent" (Baoquan He):
 
   Remove redundant GFP_DMA flags from coherent DMA allocation calls.  The
   DMA API already selects the zone from device limits and ignores the
   caller's flag.
 
 - "kselftest: mm: fix intermittent failure khugepaged test" (Yeoreum Yun):
 
   Propagate child-process failures in the khugepaged tests and prevent
   background collapse from racing their checks.  This removes false passes
   and intermittent failures.
 
 - "MAINTAINERS: cover all hugetlb headers under HUGETLB SUBSYSTEM"
   (Enze Li):
 
   Cover all hugetlb headers in MAINTAINERS so get_maintainer.pl finds the
   right maintainers.  Also label the closing hugetlb_cgroup.h include
   guard.
 
 Summary of the 65 singletons in this merge:
 
 The singletons include a few worthwhile performance fixes. Avoiding
 unnecessary reverse-map tree updates gave a reported 15.9% improvement
 in UnixBench's execl test on a 192-core x86 system. A reclaim retry fix
 stops defrag_mode from spinning under memory.low protection; a reported
 file-creation stress test ran 5.7 times faster, with far less memory
 pressure. Narrower hugetlb invalidations also spare KVM guests needless
 refaults: the reported Redis-in-VM P99 QPS penalty while punching holes
 fell from 7.09% to 1.45%.
 
 Several fixes prevent lost data or corrupted memory. Lazyfree huge-page
 races with mremap()/munmap() could lose data or access freed memory, and
 MADV_COLD could lose a concurrent write's dirty bit. Another fix
 prevents stale migration entries from outliving large folios. On
 filesystems with blocks smaller than a page, extending a file by 4 GiB
 or more could expose bytes written past the old EOF through mmap instead
 of zeroes. That is fixed, along with use-after-free races in
 PAGEMAP_SCAN during process exit and in memory-cgroup accounting on
 PREEMPT_RT kernels.
 
 Other fixes stop UFFDIO_MOVE spinning forever on pinned large folios,
 which could wedge other memory operations, and stop mremap() leaking
 commit charges until allocations fail under strict overcommit. A further
 fix keeps userfaultfd tracking intact on neighboring mappings. NUMA
 binding no longer prevents long-term pins when the chosen node has only
 movable memory, fixing QEMU/VFIO startup and io_uring buffer
 registration failures. MGLRU also gets a fix for early-boot crashes with
 memory cgroups disabled at boot, notably in small crash kernels.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCat66sAAKCRDdBJ7gKXxA
 jrQrAP99kgSXRdlmRZbHeRBHQ6KvI4XnLvQ78MDIzZ3zmBaOugEA5jiIsK2/snFD
 3VaV0oipVZpuwJkVJE6zFkh0tcHgTAo=
 =DHrN
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2026-10-25-19-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull more MM updates from Andrew Morton:

 - "mm: make VMA flag semantics explicit, eliminate VM_SPECIAL" (Lorenzo
   Stoakes):

   Replace VM_SPECIAL with helpers describing mapping ownership and
   behavior. Enforce the mmap flag rules and convert affected drivers,
   removing ambiguous tests shared by driver mappings and ordinary
   memory.

 - "support kselftest on nommu platform" (Hajime Tazaki):

   Add opt-in mmap and mremap tests for NOMMU systems. Teach the runner
   to avoid its fork-dependent timeout command and document the build
   and runtime requirements.

 - "mm/collapse: separate a collapse from its callers" (Kiryl
   Shutsemau):

   Separate huge-page collapse from caller policy. Replace khugepaged
   identity checks with explicit permissions, and separate scanning from
   collapse with the mmap_lock drop in one place.

 - "mm: implement and use vma_has_anon_rmap(), silence KCSAN" (Lorenzo
   Stoakes):

   Provide a common helper for testing whether a VMA has anonymous
   reverse mappings. Document the locking rules, annotate intentional
   concurrent reads for KCSAN, and convert the core MM callers.

 - "mm/sparse: remove SECTION_MARKED_PRESENT and further cleanups"
   (David Hildenbrand):

   Remove SECTION_MARKED_PRESENT in favor of the early-section flag.
   Simplify sparse memory initialization, section metadata handling and
   related PFN validity checks.

 - "sh: remove NUMA and SPARSEMEM support" (Mike Rapoport):

   Remove SuperH NUMA and SPARSEMEM support. The extra memory banks have
   been unusable since the NO_BOOTMEM conversion, leaving only the code
   and data overhead.

 - "mm: Unify device DAX and HugeTLB vmemmap population paths" (Muchun
   Song):

   Unify the generic device DAX and HugeTLB vmemmap population paths and
   shared tail-page handling. Remove the duplicate DAX machinery while
   retaining the powerpc radix implementation.

 - "kselftest: mm: fix some failure of split_huge_page_test" (Yeoreum
   Yun):

   Fix huge-page split tests racing with khugepaged recollapse. Use
   pagemap and page flags instead of VMA-boundary assumptions which fail
   when glibc has already enabled THP.

 - "memcg: move memcgid refcount to objcg to unpin dying memcgs"
   (Bingfang Guo):

   Let dying memcgs be freed while swapped-out shmem still holds their
   IDs. Move ID references to reparentable objcgs, with the necessary
   swap accounting and RCU lifetime changes.

 - "mm/truncate: fix data loss when truncating straddling large folios"
   (Zhang Yi):

   Preserve out-of-range data when truncating straddling large folios.
   Fix a lookup race and split-failure handling, and handle minimum
   folio orders for the forthcoming ext4 iomap buffered I/O path.

 - "mm/damon: introduce damos quota goal target metric complement flag"
   (SJ Park):

   Let DAMOS quota goals use a metric's complement, so utilization can
   also express free-memory goals without adding separate metrics. Add
   the sysfs interface, documentation and tests.

 - "arm64/mm: Standardize printing for pgtable entries" (Anshuman
   Khandual):

   Use the generic formatter for arm64 page-table entries, ready for
   future wider entries. Move the safe-PTE-update check out of the
   header to avoid an include cycle.

 - "mm: kmsan: fix iounmap metadata teardown" (Dima Koziuk):

   Fix KMSAN metadata leaks on iounmap and failed ioremap allocations.
   Free backing pages before removing their mappings, and share the
   teardown with partial-allocation cleanup.

 - "mm/damon/core: preserve quota state when constructing schemes" (Karl
   Mehltretter):

   Preserve running DAMOS quota state while validating parameter
   updates. Even rejected updates could reset accounting and exceed the
   quota window; add tests for both accepted and rejected updates.

 - "mm/vmalloc: fix vmalloc_dump_obj VA lookup" (Ye Liu):

   Fix vmalloc_dump_obj() lookups for last-page addresses and
   allocations spanning vmap zones. These allocations were being missed
   in diagnostic output.

 - "mm: various (urgent?) fixes" (David Hildenbrand):

   Fix mmap charge leaks and hugetlb use-after-free, wrong-address
   unmapping, stuck locks and endless faults. Also preserve reservations
   on failed mremap and handle stale userfaultfd bits.

 - "maple_tree: fix maple_range_64 crashes in RCU mode" (Dimitris
   Charisis):

   Fix pointer and metadata confusion during RCU destruction of
   maple_range_64 nodes, avoiding double frees and invalid accesses. Add
   a regression test; no in-tree user currently uses this combination.

 - "mm: fix hugetlb NR_HUGETLB accounting on folio migration" (Hongfu
   Li):

   Fix hugetlb migration and preallocation accounting so /proc/vmstat
   retains the correct count and memory.numa_stat follows the folio to
   its new node.

 - "mm/damon: fix a minor bug, clean code, and add a test" (SJ Park):

   Fix 32-bit DAMON age overflow which made old regions look young.
   Share hugetlb folio acquisition code and add a regression test for
   the previously fixed last-region skipping bug.

 - "mm/damon/core: cleanup code, reduce stack usage, and add kunit" (SJ
   Park):

   Reduce kdamond stack usage and remove unused enums. Add deterministic
   PSI quota-goal tests which do not depend on the machine's current
   memory pressure.

 - "mm/damon: fix the temporal goal tuner's size quota conversion"
   (Donggeun Yoo):

   Bound the temporal tuner's quota conversion to prevent overflow and
   zero effective quotas, which could stop schemes making progress. Add
   boundary tests.

 - "Don't use GFP_DMA when calling dma_alloc_coherent" (Baoquan He):

   Remove redundant GFP_DMA flags from coherent DMA allocation calls.
   The DMA API already selects the zone from device limits and ignores
   the caller's flag.

 - "kselftest: mm: fix intermittent failure khugepaged test" (Yeoreum
   Yun):

   Propagate child-process failures in the khugepaged tests and prevent
   background collapse from racing their checks. This removes false
   passes and intermittent failures.

 - "MAINTAINERS: cover all hugetlb headers under HUGETLB SUBSYSTEM"
   (Enze Li):

   Cover all hugetlb headers in MAINTAINERS so get_maintainer.pl finds
   the right maintainers. Also label the closing hugetlb_cgroup.h
   include guard.

Summary of the 65 singletons in this merge:

  The singletons include a few worthwhile performance fixes. Avoiding
  unnecessary reverse-map tree updates gave a reported 15.9% improvement
  in UnixBench's execl test on a 192-core x86 system. A reclaim retry
  fix stops defrag_mode from spinning under memory.low protection; a
  reported file-creation stress test ran 5.7 times faster, with far less
  memory pressure. Narrower hugetlb invalidations also spare KVM guests
  needless refaults: the reported Redis-in-VM P99 QPS penalty while
  punching holes fell from 7.09% to 1.45%.

  Several fixes prevent lost data or corrupted memory. Lazyfree
  huge-page races with mremap()/munmap() could lose data or access freed
  memory, and MADV_COLD could lose a concurrent write's dirty bit.
  Another fix prevents stale migration entries from outliving large
  folios. On filesystems with blocks smaller than a page, extending a
  file by 4 GiB or more could expose bytes written past the old EOF
  through mmap instead of zeroes. That is fixed, along with
  use-after-free races in PAGEMAP_SCAN during process exit and in
  memory-cgroup accounting on PREEMPT_RT kernels.

  Other fixes stop UFFDIO_MOVE spinning forever on pinned large folios,
  which could wedge other memory operations, and stop mremap() leaking
  commit charges until allocations fail under strict overcommit. A
  further fix keeps userfaultfd tracking intact on neighboring mappings.
  NUMA binding no longer prevents long-term pins when the chosen node
  has only movable memory, fixing QEMU/VFIO startup and io_uring buffer
  registration failures. MGLRU also gets a fix for early-boot crashes
  with memory cgroups disabled at boot, notably in small crash kernels.

* tag 'mm-stable-2026-10-25-19-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (213 commits)
  mm: multi-gen LRU: fix NULL lruvec->pgdat deref with memcg disabled on cmdline
  mm/page_counter: use WRITE_ONCE() for emin/elow when parent is the root
  mm/memcontrol: publish null pointer before dropping css reference
  test_maple_tree: test maple_range_64 node in RCU mode
  maple_tree: fix maple_range_64 crashes in RCU mode
  mm/vma: avoid broken uffd merge on mremap
  tools/testing/shared: catch a failed posix_memalign()
  mm/damon/core: remove unreachable damos charge_{target,addr}_from
  mm/shrinker: allocate shrinker_info_unit from a dedicated kmem_cache
  riscv: mm: exclude invalid THP PMDs from page table check
  mm/damon/core: filter out damos address filter-split failed region
  fs/proc/task_mmu: pin mm_users in do_pagemap_scan()
  mm/mempolicy: apply bind policies against the scoped allocation zone
  mm/vmscan: reclaim every zone in per-node proactive reclaim
  mm/mremap: correctly uncharge accountable VMAs in error path
  mm/mremap: populate calculated fields in vrm state correctly
  MAINTAINERS: add an entry for MEMORY MANAGEMENT - MEMORY MAP
  mm: bdi: reset min_ratio after the sysfs attributes are gone
  mm/page_vma_mapped: continue past nonmatching huge PMDs
  selftests/mm: skip hugetlb cgroup v2 tests without the needed controllers
  ...
2026-10-27 12:23:17 -10:00
Weilin Tong
e387ebe5cd ipc/shm: fix RSS accounting for hugetlb shared memory
Commit a08c7193e4 ("mm/filemap: remove hugetlb special casing in
filemap.c") changed mapping->nrpages to count base pages for hugetlb
folios.  However, shm_add_rss_swap() still multiplies it by
pages_per_huge_page(), overcounting RSS in both SHM_INFO and
/proc/sysvipc/shm.

Use mapping->nrpages for RSS accounting across all backing types, and
account swap only for non-hugetlb shmem.  Use READ_ONCE() for both
counters instead of info->lock, which does not protect nrpages and cannot
provide a consistent snapshot.

Link: https://lore.kernel.org/20261014082218.2236088-1-tongweilin@linux.alibaba.com
Fixes: a08c7193e4 ("mm/filemap: remove hugetlb special casing in filemap.c")
Signed-off-by: Weilin Tong <tongweilin@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Suggested-by: Muchun Song <muchun.song@linux.dev>
Acked-by: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@kernel.org>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: <stable@vger.kernel.org>
2026-10-24 01:56:34 -07:00
Linus Torvalds
7a78f7ba9f slab changes for 7.4
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQQQ1ub6gR5ogjaKRmOGXBN6rc5S1gUCatX5aQAKCRCGXBN6rc5S
 1hKSAP4ncSS2iyh/5OaMQ4JPEOpo3DC4r91mUCSCwggFeKrr+QEAxK57+Jc5X2fi
 3Jv2hef/wXVYMwBkIC7DlDo027GLewk=
 =18LZ
 -----END PGP SIGNATURE-----

Merge tag 'slab-for-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mm/slab

Pull slab updates from Harry Yoo:

 - Performance improvement of the sheaf prefill API, by allowing the
   barn to hold a partial sheaf and refilling sheaves from the barn.
   This improves will-it-scale mmap1 throughput by 24% on the maple_node
   cache (Hao Li)

 - Restore memcg accounting of ipc msg_msg allocations, lost with e.g.
   CONFIG_SLAB_BUCKETS=n where the allocations fall back to the general
   kmalloc caches (Kees Cook)

 - Fix an old race between kmem_cache_destroy() and slab_late_init(),
   where a cache destroyed late in the boot process tries to release a
   kobject that was never initialized (Imre Kaloz)

 - Remove slab_folio(), the last use of struct folio in slab code
   (Matthew Wilcox)

 - Reject kmalloc() requests above KMALLOC_MAX_SIZE explicitly with a
   warning and NULL return instead of relying on the page allocator's
   order check (Zi Yan)

 - Various minor fixes and cleanups (Hao Li, Karl Mehltretter, Kees
   Cook, Longlong Xia)

* tag 'slab-for-7.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mm/slab:
  mm/slub: initialize the free pointer of the bootstrap kmem_cache_node
  mm/slab: sample slab_state once in kmem_cache_destroy()
  ipc, msg: Account msg_msg allocations with GFP_KERNEL_ACCOUNT again
  mm/slab: Mark the kmem_buckets_create() context as a Context: section
  slab: Remove slab_folio()
  mm/slub: refill prefilled sheaves from the barn
  mm/slub: make the case handling in __slab_free() easier to follow
  mm/slub: unify slub stat definitions to simplify metric additions
  mm/slab_common: reject zero object_size before calculate_alignment
  mm/slab: reject unsupported kmalloc() sizes
2026-10-23 09:51:16 -10:00
Linus Torvalds
00b04f4495 vfs-7.4-rc1.idmap
Please consider pulling these changes from the signed vfs-7.4-rc1.idmap tag.
 
 Thanks!
 Christian
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCatHrlgAKCRCRxhvAZXjc
 opFuAPwLL5l3D3GSRyD+SyOjKYThylgowvH9c2BcLWbSAIO6yQD9F05GX+rrcbUq
 9ijolxAaQZYpEWsemZIIHx6BBwdDBA4=
 =IH8Z
 -----END PGP SIGNATURE-----

Merge tag 'vfs-7.4-rc1.idmap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs idmap constification from Christian Brauner:
 "This makes struct mnt_idmap const throughout the tree.

  A mount's idmapping is immutable. The only thing modified after
  alloc_mnt_idmap() is the reference count and that is hidden behind
  mnt_idmap_get() and mnt_idmap_put(). Everything else only reads from
  it. That is the same model struct cred uses and the idmapping is
  sensitive enough to deserve it.

  The conversion goes bottom up through the vfs{g,u}id and fs{g,u}id
  helpers, the privilege checks, acl, xattr and quota and then every
  inode operation that takes an idmap, so ->permission(), ->getattr(),
  ->setattr(), ->create(), ->mkdir(), ->mknod(), ->symlink(),
  ->rename(), ->tmpfile(), ->get_acl(), ->set_acl() and ->fileattr_set()
  with their implementations in every filesystem, plus the LSM hooks.

  struct vfsmount, struct mount_kattr and struct kstatmount store a
  const pointer and nop_mnt_idmap and invalid_mnt_idmap live in rodata,
  so anything that tries to modify them faults instead of silently
  corrupting the initial idmapping"

* tag 'vfs-7.4-rc1.idmap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (27 commits)
  fs: make nop_mnt_idmap and invalid_mnt_idmap const
  fs: port mnt_idmap() and file_mnt_idmap() to const mnt_idmap
  fs: port vfs_*() helpers to const mnt_idmap
  fs: port ->setattr() to pass const mnt_idmap
  fs: port ->getattr() to pass const mnt_idmap
  fs: port ->create() to pass const mnt_idmap
  fs: port ->symlink() to pass const mnt_idmap
  fs: port ->mkdir() to pass const mnt_idmap
  fs: port ->rename() to pass const mnt_idmap
  fs: port ->mknod() to pass const mnt_idmap
  fs: port ->tmpfile() to pass const mnt_idmap
  fs: port ->get_acl() to pass const mnt_idmap
  fs: port ->set_acl() to pass const mnt_idmap
  fs: port ->fileattr_set() to pass const mnt_idmap
  fs: port xattr to const mnt_idmap
  fs: port ->permission() to pass const mnt_idmap
  fs: port acl to const mnt_idmap
  fs: port inode_init_owner() to const mnt_idmap
  fs: port inode_owner_or_capable() to const mnt_idmap
  fs: port privilege checking helpers to const mnt_idmap
  ...
2026-10-19 17:57:49 -10:00
Linus Torvalds
def41b7bd4 ipc-7.4-rc1.misc
Please consider pulling these changes from the signed ipc-7.4-rc1.misc tag.
 
 Thanks!
 Christian
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCatHrlQAKCRCRxhvAZXjc
 omTYAPkBx1efHh/CYYRuxLKrV91qPXudLFky3pnQg7TnOJseTQD+OhT3Dk53T0CN
 46LdledXlcU7uiCG7gSMY72XWXvL1Ac=
 =M1pi
 -----END PGP SIGNATURE-----

Merge tag 'ipc-7.4-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull ipc fix from Christian Brauner:
 "This fixes a leak in mqueue.

  A task in another thread group sharing the file table could register
  an mq_notify() and exit without closing the queue. The registration
  was never torn down and pinned the notification skb, the netlink
  socket, a pid reference and a user namespace reference forever.

  Stale registrations are released on inode eviction now"

* tag 'ipc-7.4-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  ipc/mqueue: release notification resources during inode eviction
2026-10-19 15:57:25 -10:00
Kees Cook
c57fbbe42e ipc, msg: Account msg_msg allocations with GFP_KERNEL_ACCOUNT again
Since commit 734bbc1c97 ("ipc, msg: Use dedicated slab buckets for
alloc_msg()"), alloc_msg() allocates with GFP_KERNEL, and a msg_msg is
accounted only through SLAB_ACCOUNT on its bucket caches. With
CONFIG_SLAB_BUCKETS=n, kmem_buckets_create() creates no caches and
kmem_buckets_alloc() is a GFP_KERNEL kmalloc() from the general caches,
which do not account it; the same happens when kmem_buckets_create()
fails. Either way, the allocation is not charged to the sender's memory
cgroup.

Allocate with GFP_KERNEL_ACCOUNT again, as before that commit, so the
allocation is charged whichever cache serves it.

Build tested ARCH=x86_64 defconfig with GCC 16.2.0, with
CONFIG_SLAB_BUCKETS as y and n.

Fixes: 734bbc1c97 ("ipc, msg: Use dedicated slab buckets for alloc_msg()")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20261014052344.384723-2-kees@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Reviewed-by: Harry Yoo (Meta) <harry@kernel.org>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Harry Yoo (Meta) <harry@kernel.org>
2026-10-16 15:52:26 +01:00
Christian Brauner
f0e48172a5
ipc: drop the mqueue mount with kern_unmount() on setup failure
mq_init_ns() creates the mqueue mount with fc_mount_longterm(), so its
->mnt_ns is MNT_NS_INTERNAL. When setting up the mqueue or ipc sysctls
or msg_init_ns() fails afterwards, create_ipc_ns() drops it with a plain
mntput(). With ->mnt_ns set that takes the fast path of
mntput_no_expire(). The count drops to zero and nothing ever kills the
mount, so the mount and the mqueue superblock are leaked.

Commit dc55e35f9e ("ipc: Store mqueue sysctls in the ipc namespace")
added the first failure path after mq_init_ns() and never dropped the
mount. Commit 7229d74e5e ("ipc: create_ipc_ns: drop mqueue mount on
sysctl setup failure") tried to fix that with a mntput() but that
doesn't help for a long-term mount.

Use kern_unmount(). free_ipc() open-codes the same thing for a namespace
that made it.

Fixes: dc55e35f9e ("ipc: Store mqueue sysctls in the ipc namespace")
Fixes: 7229d74e5e ("ipc: create_ipc_ns: drop mqueue mount on sysctl setup failure")
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20261009-work-fixes-rcu-v1-5-7446d2d335e6@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-10-14 22:08:03 +02:00
Christian Brauner
eb50cbe14f
fs: port ->create() to pass const mnt_idmap
Convert to const struct mnt_idmap.

A mount's idmapping is immutable. The only thing that is allowed to be
modified afterwards is the reference count and that is hidden behind
mnt_idmap_get() and mnt_idmap_put(). Everything else only ever reads
from the idmapping. This is the same model that struct cred uses and the
idmapping is also rather sensitive.

So make the idmap argument const wherever we can. The conversion is done
from the bottom up so callers can continue to pass a non-const pointer
to a const parameter until the conversion is finished.

No functional changes.

Link: https://patch.msgid.link/20260901-work-idmap-const-v1-22-54ccd48e100b@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Seth Forshee <sforshee@kernel.org>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-09-23 09:19:51 +02:00
Daehyeon Ko
eb85469f0d
ipc/mqueue: release notification resources during inode eviction
mqueue_flush_file() removes an mq_notify() registration only when the
closing task belongs to the thread group stored in notify_owner.

A task in a separate thread group created with CLONE_FILES can register
SIGEV_THREAD notification and exit without closing the shared file table.
If another thread group then unlinks and last-closes the queue, ->flush()
skips the registration and inode eviction loses the only pointers to its
resources.

The orphaned registration permanently retains the notification skb, its
netlink socket, a pid reference and a user namespace reference. An
unprivileged process can repeat the sequence with new queues and sockets.

No inode users remain during eviction. Remove any stale registration there
after dropping info->lock, since netlink_sendskb() may release the final
socket reference.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Daehyeon Ko <4ncienth@gmail.com>
Link: https://patch.msgid.link/20260824042359.925145-1-4ncienth@gmail.com
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-08-31 12:30:30 +02:00
Linus Torvalds
e5f9260615 mm.git review status for master..mm-nonmm-stable
Total patches:       95
 Reviews/patch:       0.63
 Reviewed rate:       56%
 
 Summary of patch series in this merge:
 
 - "ocfs2/dlm: bound peer-controlled lengths in the o2dlm" (Bryam Vargas):
 
   Validate and bound all input lengths and count fields in the o2dlm
   migration and recovery receive handlers to prevent memory corruption and
   kernel panics from malformed cluster messages
 
 - "ocfs2: validate xattr entry bounds" (Cen Zhang):
 
   Validate OCFS2 extended attribute entry name and value bounds during
   metadata reads to prevent out-of-range memory accesses during retrieval
   or listing operations.
 
 - "taskstats: fix cgroupstats invalid fd handling and add selftests"
   (Yiyang Chen):
 
   Return -EBADF when cgroupstats receives an invalid file descriptor to
   prevent caller hangs and misleading success ACKs.  Add a kselftest to
   validate valid cgroup v1 queries and verify proper error handling across
   different Netlink flag combinations.
 
 - "misc lib/raid/ improvements v2" (Christoph Hellwig):
 
   Improve benchmark-based algorithm selection for the XOR and RAID6
   libraries, add KUnit benchmark tests, and cleanup minor implementation
   details.
 
 - "ocfs2: cluster: o2hb_region_pin() fixes" (Joseph Qi):
 
   Fix sleeping-in-atomic, lock order inversion and error-path cleanup
   bugs in o2hb_region_pin() by releasing o2hb_live_lock across sleeping
   configfs_depend_item() calls and using unlocked variants from callback
   context.  Ensure failed pin attempts properly decrement user counts and
   unpin partially initialized heartbeat regions to prevent memory leaks
   and unprotected states.
 
 - "lib/ucs2_string.c: fix out-of-bounds read in ucs2_strnlen()" (Vincent
   Mailhol)
 
   Fix an off-by-one which could cause an out-of-bounds read.
 
 - "ocfs2: harden heartbeat teardown races" (Cen Zhang):
 
   Fix two OCFS2 heartbeat/o2net teardown races found by KASAN.
 
 - "taskstats: tidy up the cpumask command path" *Bradley Morgan)
 
   make two small cleanups in kernel/taskstats.c.
 
 - "ocfs2: validate active orphan slots during inode read" (ZhengYuan Huang):
 
   Validate active ordinary and append-DIO orphan slots read from OCFS2
   dinodes at the metadata boundary to prevent corrupted slot indices from
   causing out-of-bounds array accesses.
 
 - "ocfs2: bound-check both readdir re-validation scans" (Zhan Xusheng)
 
   Enforce strict boundary checks on directory entry record lengths and
   offset calculations during OCFS2 directory re-scans to prevent
   out-of-bounds memory reads and directory position corruption.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaoo38wAKCRDdBJ7gKXxA
 jnKuAP9tIUJoYIzxG7zr00qJj95gczgE0+GikN1wXfO9Cvh8QAEAqr5InWrANTBB
 l4qW3/o4hM9TlBdr84oT3RNnvBicuwA=
 =BY1d
 -----END PGP SIGNATURE-----

Merge tag 'mm-nonmm-stable-2026-08-22-16-57' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - "ocfs2/dlm: bound peer-controlled lengths in the o2dlm" (Bryam
   Vargas)

   Validate and bound all input lengths and count fields in the o2dlm
   migration and recovery receive handlers to prevent memory corruption
   and kernel panics from malformed cluster messages

 - "ocfs2: validate xattr entry bounds" (Cen Zhang)

   Validate OCFS2 extended attribute entry name and value bounds during
   metadata reads to prevent out-of-range memory accesses during
   retrieval or listing operations.

 - "taskstats: fix cgroupstats invalid fd handling and add selftests"
   (Yiyang Chen)

   Return -EBADF when cgroupstats receives an invalid file descriptor to
   prevent caller hangs and misleading success ACKs. Add a kselftest to
   validate valid cgroup v1 queries and verify proper error handling
   across different Netlink flag combinations.

 - "misc lib/raid/ improvements v2" (Christoph Hellwig)

   Improve benchmark-based algorithm selection for the XOR and RAID6
   libraries, add KUnit benchmark tests, and cleanup minor
   implementation details.

 - "ocfs2: cluster: o2hb_region_pin() fixes" (Joseph Qi)

   Fix sleeping-in-atomic, lock order inversion and error-path cleanup
   bugs in o2hb_region_pin() by releasing o2hb_live_lock across sleeping
   configfs_depend_item() calls and using unlocked variants from
   callback context. Ensure failed pin attempts properly decrement user
   counts and unpin partially initialized heartbeat regions to prevent
   memory leaks and unprotected states.

 - "lib/ucs2_string.c: fix out-of-bounds read in ucs2_strnlen()"
   (Vincent Mailhol)

   Fix an off-by-one which could cause an out-of-bounds read.

 - "ocfs2: harden heartbeat teardown races" (Cen Zhang)

   Fix two OCFS2 heartbeat/o2net teardown races found by KASAN.

 - "taskstats: tidy up the cpumask command path" *Bradley Morgan)

   make two small cleanups in kernel/taskstats.c.

 - "ocfs2: validate active orphan slots during inode read" (ZhengYuan
   Huang)

   Validate active ordinary and append-DIO orphan slots read from OCFS2
   dinodes at the metadata boundary to prevent corrupted slot indices
   from causing out-of-bounds array accesses.

 - "ocfs2: bound-check both readdir re-validation scans" (Zhan Xusheng)

   Enforce strict boundary checks on directory entry record lengths and
   offset calculations during OCFS2 directory re-scans to prevent
   out-of-bounds memory reads and directory position corruption.

* tag 'mm-nonmm-stable-2026-08-22-16-57' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (95 commits)
  mailmap: fix bouncing address for Taniya Das
  ocfs2: bound-check dir entries in the inline-data re-validation scan
  ocfs2: bound-check dir entries in the readdir re-validation scan
  squashfs: avoid thundering-herd cache wakeups
  prctl: fix PR_SET_MM_AUXV losing the forced AT_NULL terminator
  mailmap: update email address for Linfeng Sun
  lib/interval_tree: fix allocation warning messages
  checkpatch: add NOKPROBE_SYMBOL to the whitelist of lines that can occur immediately after functions
  Squashfs: check block offset is not negative
  signal: factor out the kernel reserved si_code check
  ocfs2: fix readdir position truncation on 32-bit kernels
  ocfs2: fix cached cluster count after suballocator reclaim
  ocfs2: fix circular locking dependency in ocfs2_init_acl()
  ocfs2: validate DIO orphan slot during inode read
  ocfs2: validate orphan slot during inode read
  selftests/prctl: fix non-anonymous VMA mapping in set-anon-vma-name test
  MAINTAINERS: add IRC and patchwork for LTP
  include/linux/list.h: mark list_add and __list_add as __always_inline
  tools/mm: prevent page_owner_sort from truncating input
  hung_task: update DETECT_HUNG_TASK_BLOCKER Kconfig help
  ...
2026-08-23 08:07:11 -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
ab5ed08f2d vfs-7.3-rc1.lookup
Please consider pulling these changes from the signed vfs-7.3-rc1.lookup tag.
 
 Thanks!
 Christian
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCan7RJQAKCRCRxhvAZXjc
 ouj6AQCnBHstCt5RRimywLYU+eTmdKe203zRQYxXpwlYOAzm7wEAm1mIC7/Of6bD
 jkiJilcPDcyYcJsqwBw/Vcz5HR+v8wo=
 =TX6K
 -----END PGP SIGNATURE-----

Merge tag 'vfs-7.3-rc1.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs lookup updates from Christian Brauner:
 "This refactors lookup_open() and adds vfs_lookup_open() for nfsd.

  mnt_want_write() and parent locking are moved into lookup_open()
  itself.

  audit_inode_child() is also now called in lookup_open() on failure.
  That is the calling convention in vfs_create() and vfs_mkdir(), but
  lookup_open() made no such call when atomic_open() should have created
  a file and did not. And neither did the regular ->create() path fwiw.

  This also contains work to remove the unneeded excl argument from the
  ->create() inode op"

* tag 'vfs-7.3-rc1.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fs/namei.c: fix coding style in atomic_open() and lookup_open()
  fs/namei.c: fix kerneldoc of atomic_open() and vfs_lookup_open()
  fs/namei.c: update stale comments in lookup_open()
  Remove excl arg to ->create inode_operation
  fs/namei.c: update kerneldoc of atomic_open()
  vfs: call audit_inode_child() in lookup_open() on failure
  vfs: move create error && negative dentry case in lookup_open() up
  VFS: add vfs_lookup_open() for nfsd
  VFS: move delegated_inode retry loop into lookup_open()
  VFS: move mnt_want_write() and locking into lookup_open()
2026-08-17 12:03:34 -07:00
Jianlin Shi
36969d97fe ipc: only destroy orphaned shm segments on sysctl write
proc_ipc_dointvec_minmax_orphans() currently calls shm_destroy_orphaned()
whenever shm_rmid_forced is set, including on sysctl reads.  Reading
/proc/sys/kernel/shm_rmid_forced should not take shm_ids rwsem for write
and walk all segments.

Only run the cleanup when the sysctl is written and the forced RMID policy
is enabled.

When shm_rmid_forced=1, monitoring tools that read
/proc/sys/kernel/shm_rmid_forced trigger the cleanup on every read.

Link: https://lore.kernel.org/all/?q=only+destroy+orphaned+shm+segments+on+sysctl+write
Link: https://lore.kernel.org/tencent_738A8BC6E9EA205F555E4B0DAA154D4F8E0A@qq.com
Signed-off-by: Jianlin Shi <shijianlin11@foxmail.com>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-13 15:42:04 -07:00
Lorenzo Stoakes
1944a0183c mm/vma: update do_mmap() to use vma_flags_t
The core do_mmap() function accepts a vm_flags_t parameter which it then
manipulates before passing to mmap_region() to do the heavy lifting of the
memory mapping.

Update do_mmap() to instead accept a vma_flags_t parameter, and adjust all
the logic within do_mmap() to manipulate this instead.

This is as part of the ongoing effort to convert VMA flags from a system
word size to a bitmap type which allows us to unrestrict the number of VMA
flags, as well as gain control over how VMA flag manipulation occurs.

We do not cascade these changes to all functions which accept vm_flags_t,
but rather use vma_flags_to_legacy() where necessary, specifically
deferring converting calc_vm_prot_bits(), calc_vm_flag_bits() and
__get_unmapped_area() to vma_flags_t.

Also utilise the new vma_flags_can_grow() predicate which correctly
handles the case of architectures without upward growing stacks.

As part of this change, introduce VMA_SHADOW_STACK so we can correctly
handle the case of the shadow stack not being defined.

No functional change intended.

Link: https://lore.kernel.org/20260711-b4-vma-flags-mm-v2-2-0fa2357d5431@kernel.org
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Dave Airlie <airlied@gmail.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nico Pache <npache@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:01 -07:00
NeilBrown
b2f1e6301e
Remove excl arg to ->create inode_operation
The only time that 'false' is passed as the 'excl' arg to the ->create
inode_operation is in lookup_open() when ->atomic_open is not provided
by the parent directory.
*all* directory inode_operations which do not have ->atomic_open
completely ignore the 'excl' arg.

Therefore we don't need the 'excl' arg.  Those few ->create operations
which pay attention to the arg are only ever called with a value of
'true'.

We remove that arg and change all ->create operations to behave as those
thhe arg were 'true'.

Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/178290671516.27465.15984496764174914338@noble.neil.brown.name
Reviewed-by: Jori Koolstra <jkoolstra@xs4all.nl>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-31 10:18:30 +02:00
Yi Xie
1184f5e820
mqueue: reject mq_notify with signo 0
valid_signal(0) is true; __do_notify() skips signo 0 anyway.

Signed-off-by: Yi Xie <xieyi@kylinos.cn>
Link: https://patch.msgid.link/20260603020936.54508-1-xieyi@kylinos.cn
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29 10:29:28 +02:00
Linus Torvalds
37c405aeaa kernel-7.2-rc1.misc
Please consider pulling these changes from the signed kernel-7.2-rc1.misc tag.
 
 Thanks!
 Christian
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaiwLKgAKCRCRxhvAZXjc
 ov8YAQC/PzS/w3jwLjZRsIzXesRtWmSVwf8W+6Df2B3sULCvkQEA8bYlzNJ8+VWx
 3mC0gIKLRtLm6h2fA04z8972xOF3DgY=
 =wmIj
 -----END PGP SIGNATURE-----

Merge tag 'kernel-7.2-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull misc kernel updates from Christian Brauner:
 "Fixes

   - rhashtable: give each instance its own lockdep class

     syzbot reported a circular locking dependency between ht->mutex and
     fs_reclaim via the simple_xattrs rhashtable being torn down during
     inode eviction.

     The predicted deadlock cannot occur: rhashtable_free_and_destroy()
     cancels the deferred worker before taking ht->mutex and
     acquisitions on distinct rhashtables are on distinct mutexes.

     Lockdep flags a cycle anyway because every ht->mutex in the kernel
     shared the single static lockdep class from
     rhashtable_init_noprof().

     The lockdep key is lifted to a per-call-site static key so every
     rhashtable instance gets its own class.

   - selftests/clone3: fix misuse of the libcap library interface in the
     cap_checkpoint_restore test and remove unused variables

   - selftests/pid_namespace: compute the pid_max test limits
     dynamically instead of hardcoding values below the kernel-enforced
     minimum of PIDS_PER_CPU_MIN * num_possible_cpus() which made the
     tests fail on machines with many possible CPUs

   - selftests: fix the Makefile TARGETS entry for nsfs which wasn't
     adjusted when the tests moved under filesystems/

  Cleanups

   - ipc/sem.c: use unsigned int for nsops to match the declaration in
     syscalls.h"

* tag 'kernel-7.2-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  selftests/clone3: remove unused variables
  selftests/clone3: fix libcap interface usage
  ipc/sem.c: use unsigned int for nsops
  selftests: Fix Makefile target for nsfs
  rhashtable: give each instance its own lockdep class
  selftests/pid_namespace: compute pid_max test limits dynamically
2026-06-15 03:05:50 +05:30
Yilin Zhu
2e5c6f4fd4 ipc/shm: serialize orphan cleanup with shm_nattch updates
shm_destroy_orphaned() walks the shm idr under shm_ids(ns).rwsem, but that
does not serialize all fields tested by shm_may_destroy().  In particular,
shm_nattch is updated while holding shm_perm.lock, and attach paths can do
that without holding the rwsem.

Do not decide that an orphaned segment is unused before taking the object
lock.  Move the shm_may_destroy() check under shm_perm.lock, matching the
other destroy paths, and unlock the segment when it no longer qualifies
for removal.

Link: https://lore.kernel.org/9d97cc1031de2d0bace0edf3a668818aa2f4eca6.1777410234.git.zylzyl2333@gmail.com
Fixes: 4c677e2eef ("shm: optimize locking and ipc_namespace getting")
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Yilin Zhu <zylzyl2333@gmail.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jeongjun Park <aha310510@gmail.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Liam Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Serge Hallyn <sergeh@kernel.org>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-06-03 16:25:49 -07:00
Yi Xie
69d18b6c90
ipc/sem.c: use unsigned int for nsops
Use unsigned int instead of unsigned for nsops parameter,
to match declaration in syscalls.h.

Signed-off-by: Yi Xie <xieyi@kylinos.cn>
Link: https://patch.msgid.link/20260525004220.19277-1-xieyi@kylinos.cn
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-05-27 14:10:25 +02:00
Linpu Yu
fa0b9b2b7a ipc: limit next_id allocation to the valid ID range
The checkpoint/restore sysctl path can request the next SysV IPC id
through ids->next_id.  ipc_idr_alloc() currently forwards that request to
idr_alloc() with an open-ended upper bound.

If the valid tail of the SysV IPC id space is full, the allocation can
spill beyond ipc_mni.  The returned SysV IPC id still uses the normal
index encoding, so later lookup and removal can target the wrong slot. 
This leaves the real IDR entry behind and breaks the IDR state for the
object.

The bug is in ipc_idr_alloc() in the checkpoint/restore path.

1. ids->next_id is passed to:

       idr_alloc(&ids->ipcs_idr, new, ipcid_to_idx(next_id), 0, ...)

2. The zero upper bound makes the allocation effectively open-ended.
   Once the valid SysV IPC tail is occupied, idr_alloc() can spill past
   ipc_mni and allocate an entry beyond the valid IPC id range.

3. The new object id is still encoded with the narrower SysV IPC index
   width:

       new->id = (new->seq << ipcmni_seq_shift()) + idx

4. Later removal goes through ipc_rmid(), which uses:

       ipcid_to_idx(ipcp->id)

   That truncates the real IDR index. An object actually stored at a
   high index can then be removed as if it lived at a low in-range
   index.

5. For shared memory, shm_destroy() frees the current object anyway, but
   the real high IDR slot is left behind as a dangling pointer.

6. A subsequent walk of /proc/sysvipc/shm reaches the stale IDR entry
   and dereferences freed memory.

Prevent this by bounding the requested allocation to ipc_mni so the
checkpoint/restore path fails once the valid range is exhausted.

Link: https://lore.kernel.org/cover.1778336914.git.linpu5433@gmail.com
Link: https://lore.kernel.org/2eebe949bfa7d1f6e13b5be6a92c64c850ce9d45.1778336914.git.linpu5433@gmail.com
Fixes: 03f5956680 ("ipc: add sysctl to specify desired next object id")
Signed-off-by: Linpu Yu <linpu5433@gmail.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Cc: Kees Cook <kees@kernel.org>
Cc: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-21 19:06:11 -07:00
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

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

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

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

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

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

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

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

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

(where TYPE may also be *VAR)

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

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Linus Torvalds
eeccf287a2 mm.git review status for linus..mm-stable
Total patches:       36
 Reviews/patch:       1.77
 Reviewed rate:       83%
 
 - The 2 patch series "mm/vmscan: fix demotion targets checks in
   reclaim/demotion" from Bing Jiao fixes a couple of issues in the
   demotion code - pages were failed demotion and were finding themselves
   demoted into disallowed nodes.
 
 - The 11 patch series "Remove XA_ZERO from error recovery of dup_mmap()"
   from Liam Howlett fixes a rare mapledtree race and performs a number of
   cleanups.
 
 - The 13 patch series "mm: add bitmap VMA flag helpers and convert all
   mmap_prepare to use them" from Lorenzo Stoakes implements a lot of
   cleanups following on from the conversion of the VMA flags into a
   bitmap.
 
 - The 5 patch series "support batch checking of references and unmapping
   for large folios" from Baolin Wang implements batching to greatly
   improve the performance of reclaiming clean file-backed large folios.
 
 - The 3 patch series "selftests/mm: add memory failure selftests" from
   Miaohe Lin does as claimed.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaZaIEQAKCRDdBJ7gKXxA
 jj73AQCQDwLoipDiQRGyjB5BDYydymWuDoiB1tlDPHfYAP3b/QD/UQtVlOEXqwM3
 naOKs3NQ1pwnfhDaQMirGw2eAnJ1SQY=
 =6Iif
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2026-02-18-19-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull more MM  updates from Andrew Morton:

 - "mm/vmscan: fix demotion targets checks in reclaim/demotion" fixes a
   couple of issues in the demotion code - pages were failed demotion
   and were finding themselves demoted into disallowed nodes (Bing Jiao)

 - "Remove XA_ZERO from error recovery of dup_mmap()" fixes a rare
   mapledtree race and performs a number of cleanups (Liam Howlett)

 - "mm: add bitmap VMA flag helpers and convert all mmap_prepare to use
   them" implements a lot of cleanups following on from the conversion
   of the VMA flags into a bitmap (Lorenzo Stoakes)

 - "support batch checking of references and unmapping for large folios"
   implements batching to greatly improve the performance of reclaiming
   clean file-backed large folios (Baolin Wang)

 - "selftests/mm: add memory failure selftests" does as claimed (Miaohe
   Lin)

* tag 'mm-stable-2026-02-18-19-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (36 commits)
  mm/page_alloc: clear page->private in free_pages_prepare()
  selftests/mm: add memory failure dirty pagecache test
  selftests/mm: add memory failure clean pagecache test
  selftests/mm: add memory failure anonymous page test
  mm: rmap: support batched unmapping for file large folios
  arm64: mm: implement the architecture-specific clear_flush_young_ptes()
  arm64: mm: support batch clearing of the young flag for large folios
  arm64: mm: factor out the address and ptep alignment into a new helper
  mm: rmap: support batched checks of the references for large folios
  tools/testing/vma: add VMA userland tests for VMA flag functions
  tools/testing/vma: separate out vma_internal.h into logical headers
  tools/testing/vma: separate VMA userland tests into separate files
  mm: make vm_area_desc utilise vma_flags_t only
  mm: update all remaining mmap_prepare users to use vma_flags_t
  mm: update shmem_[kernel]_file_*() functions to use vma_flags_t
  mm: update secretmem to use VMA flags on mmap_prepare
  mm: update hugetlbfs to use VMA flags on mmap_prepare
  mm: add basic VMA flag operation helper functions
  tools: bitmap: add missing bitmap_[subset(), andnot()]
  mm: add mk_vma_flags() bitmap flag macro helper
  ...
2026-02-18 20:50:32 -08:00
Linus Torvalds
543b9b6339 kernel-7.0-rc1.misc
Please consider pulling these changes from the signed kernel-7.0-rc1.misc tag.
 
 Thanks!
 Christian
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaZL+JwAKCRCRxhvAZXjc
 ovU/AP4xgVxEegnNYrXZ+TpdCXbCtQZ54JqowFX73MBtaBHY1QD/YkDaIzl6K70v
 d9P2Fe8Y6wOnIHxcjE4MIdMansphjAM=
 =TN3q
 -----END PGP SIGNATURE-----

Merge tag 'kernel-7.0-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull pidfs updates from Christian Brauner:

 - pid: introduce task_ppid_vnr() helper

 - pidfs: convert rb-tree to rhashtable

   Mateusz reported performance penalties during task creation because
   pidfs uses pidmap_lock to add elements into the rbtree. Switch to an
   rhashtable to have separate fine-grained locking and to decouple from
   pidmap_lock moving all heavy manipulations outside of it

   Also move inode allocation outside of pidmap_lock. With this there's
   nothing happening for pidfs under pidmap_lock

 - pid: reorder fields in pid_namespace to reduce false sharing

 - Revert "pid: make __task_pid_nr_ns(ns => NULL) safe for zombie
   callers"

 - ipc: Add SPDX license id to mqueue.c

* tag 'kernel-7.0-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  pid: introduce task_ppid_vnr() helper
  pidfs: implement ino allocation without the pidmap lock
  Revert "pid: make __task_pid_nr_ns(ns => NULL) safe for zombie callers"
  pid: reorder fields in pid_namespace to reduce false sharing
  pidfs: convert rb-tree to rhashtable
  ipc: Add SPDX license id to mqueue.c
2026-02-16 12:37:13 -08:00
Lorenzo Stoakes
590d356aa4 mm: update shmem_[kernel]_file_*() functions to use vma_flags_t
In order to be able to use only vma_flags_t in vm_area_desc we must adjust
shmem file setup functions to operate in terms of vma_flags_t rather than
vm_flags_t.

This patch makes this change and updates all callers to use the new
functions.

No functional changes intended.

[akpm@linux-foundation.org: comment fixes, per Baolin]
Link: https://lkml.kernel.org/r/736febd280eb484d79cef5cf55b8a6f79ad832d2.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Yury Norov <ynorov@nvidia.com>
Cc: Chris Mason <clm@fb.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-12 15:42:58 -08:00
Lorenzo Stoakes
097e8db5e2 mm: update hugetlbfs to use VMA flags on mmap_prepare
In order to update all mmap_prepare users to utilising the new VMA flags
type vma_flags_t and associated helper functions, we start by updating
hugetlbfs which has a lot of additional logic that requires updating to
make this change.

This is laying the groundwork for eliminating the vm_flags_t from struct
vm_area_desc and using vma_flags_t only, which further lays the ground for
removing the deprecated vm_flags_t type altogether.

No functional changes intended.

Link: https://lkml.kernel.org/r/9226bec80c9aa3447cc2b83354f733841dba8a50.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Yury Norov <ynorov@nvidia.com>
Cc: Chris Mason <clm@fb.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-12 15:42:57 -08:00
Linus Torvalds
136114e0ab mm.git review status for linus..mm-nonmm-stable
Total patches:       107
 Reviews/patch:       1.07
 Reviewed rate:       67%
 
 - The 2 patch series "ocfs2: give ocfs2 the ability to reclaim
   suballocator free bg" from Heming Zhao saves disk space by teaching
   ocfs2 to reclaim suballocator block group space.
 
 - The 4 patch series "Add ARRAY_END(), and use it to fix off-by-one
   bugs" from Alejandro Colomar adds the ARRAY_END() macro and uses it in
   various places.
 
 - The 2 patch series "vmcoreinfo: support VMCOREINFO_BYTES larger than
   PAGE_SIZE" from Pnina Feder makes the vmcore code future-safe, if
   VMCOREINFO_BYTES ever exceeds the page size.
 
 - The 7 patch series "kallsyms: Prevent invalid access when showing
   module buildid" from Petr Mladek cleans up kallsyms code related to
   module buildid and fixes an invalid access crash when printing
   backtraces.
 
 - The 3 patch series "Address page fault in
   ima_restore_measurement_list()" from Harshit Mogalapalli fixes a
   kexec-related crash that can occur when booting the second-stage kernel
   on x86.
 
 - The 6 patch series "kho: ABI headers and Documentation updates" from
   Mike Rapoport updates the kexec handover ABI documentation.
 
 - The 4 patch series "Align atomic storage" from Finn Thain adds the
   __aligned attribute to atomic_t and atomic64_t definitions to get
   natural alignment of both types on csky, m68k, microblaze, nios2,
   openrisc and sh.
 
 - The 2 patch series "kho: clean up page initialization logic" from
   Pratyush Yadav simplifies the page initialization logic in
   kho_restore_page().
 
 - The 6 patch series "Unload linux/kernel.h" from Yury Norov moves
   several things out of kernel.h and into more appropriate places.
 
 - The 7 patch series "don't abuse task_struct.group_leader" from Oleg
   Nesterov removes the usage of ->group_leader when it is "obviously
   unnecessary".
 
 - The 5 patch series "list private v2 & luo flb" from Pasha Tatashin
   adds some infrastructure improvements to the live update orchestrator.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaY4giAAKCRDdBJ7gKXxA
 jgusAQDnKkP8UWTqXPC1jI+OrDJGU5ciAx8lzLeBVqMKzoYk9AD/TlhT2Nlx+Ef6
 0HCUHUD0FMvAw/7/Dfc6ZKxwBEIxyww=
 =mmsH
 -----END PGP SIGNATURE-----

Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

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

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

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

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

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

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

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

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

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

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

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

* tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits)
  watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency
  procfs: fix missing RCU protection when reading real_parent in do_task_stat()
  watchdog/softlockup: fix sample ring index wrap in need_counting_irqs()
  kcsan, compiler_types: avoid duplicate type issues in BPF Type Format
  kho: fix doc for kho_restore_pages()
  tests/liveupdate: add in-kernel liveupdate test
  liveupdate: luo_flb: introduce File-Lifecycle-Bound global state
  liveupdate: luo_file: Use private list
  list: add kunit test for private list primitives
  list: add primitives for private list manipulations
  delayacct: fix uapi timespec64 definition
  panic: add panic_force_cpu= parameter to redirect panic to a specific CPU
  netclassid: use thread_group_leader(p) in update_classid_task()
  RDMA/umem: don't abuse current->group_leader
  drm/pan*: don't abuse current->group_leader
  drm/amd: kill the outdated "Only the pthreads threading model is supported" checks
  drm/amdgpu: don't abuse current->group_leader
  android/binder: use same_thread_group(proc->tsk, current) in binder_mmap()
  android/binder: don't abuse current->group_leader
  kho: skip memoryless NUMA nodes when reserving scratch areas
  ...
2026-02-12 12:13:01 -08:00
Tim Bird
a344860211
ipc: Add SPDX license id to mqueue.c
Add GPL-2.0 license id to file, replacing reference to
GPL in the header comment.

Signed-off-by: Tim Bird <tim.bird@sony.com>
Link: https://patch.msgid.link/20260117202759.692347-1-tim.bird@sony.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-02-10 11:39:30 +01:00
Ondrej Mosnacek
8924336531 ipc: don't audit capability check in ipc_permissions()
The IPC sysctls implement the ctl_table_root::permissions hook and they
override the file access mode based on the CAP_CHECKPOINT_RESTORE
capability, which is being checked regardless of whether any access is
actually denied or not, so if an LSM denies the capability, an audit
record may be logged even when access is in fact granted.

It wouldn't be viable to restructure the sysctl permission logic to only
check the capability when the access would be actually denied if it's not
granted.  Thus, do the same as in net_ctl_permissions() (net/sysctl_net.c)
- switch from ns_capable() to ns_capable_noaudit(), so that the check
never emits an audit record.

Link: https://lkml.kernel.org/r/20260122141303.241133-1-omosnace@redhat.com
Fixes: 0889f44e28 ("ipc: Check permissions for checkpoint_restart sysctls at open time")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Alexey Gladkov <legion@kernel.org>
Acked-by: Serge Hallyn <serge@hallyn.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Paul Moore <paul@paul-moore.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-31 16:16:07 -08:00
Al Viro
abb0434496 mqueue: switch to CLASS(filename)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2026-01-16 12:52:04 -05:00
Linus Torvalds
509d3f4584 Significant patch series in this pull request:
- The 6 patch series "panic: sys_info: Refactor and fix a potential
   issue" from Andy Shevchenko fixes a build issue and does some cleanup in
   ib/sys_info.c.
 
 - The 9 patch series "Implement mul_u64_u64_div_u64_roundup()" from
   David Laight enhances the 64-bit math code on behalf of a PWM driver and
   beefs up the test module for these library functions.
 
 - The 2 patch series "scripts/gdb/symbols: make BPF debug info available
   to GDB" from Ilya Leoshkevich makes BPF symbol names, sizes, and line
   numbers available to the GDB debugger.
 
 - The 4 patch series "Enable hung_task and lockup cases to dump system
   info on demand" from Feng Tang adds a sysctl which can be used to cause
   additional info dumping when the hung-task and lockup detectors fire.
 
 - The 6 patch series "lib/base64: add generic encoder/decoder, migrate
   users" from Kuan-Wei Chiu adds a general base64 encoder/decoder to lib/
   and migrates several users away from their private implementations.
 
 - The 2 patch series "rbree: inline rb_first() and rb_last()" from Eric
   Dumazet makes TCP a little faster.
 
 - The 9 patch series "liveupdate: Rework KHO for in-kernel users" from
   Pasha Tatashin reworks the KEXEC Handover interfaces in preparation for
   Live Update Orchestrator (LUO), and possibly for other future clients.
 
 - The 13 patch series "kho: simplify state machine and enable dynamic
   updates" from Pasha Tatashin increases the flexibility of KEXEC
   Handover.  Also preparation for LUO.
 
 - The 18 patch series "Live Update Orchestrator" from Pasha Tatashin is
   a major new feature targeted at cloud environments.  Quoting the [0/N]:
 
     This series introduces the Live Update Orchestrator, a kernel subsystem
     designed to facilitate live kernel updates using a kexec-based reboot.
     This capability is critical for cloud environments, allowing hypervisors
     to be updated with minimal downtime for running virtual machines.  LUO
     achieves this by preserving the state of selected resources, such as
     memory, devices and their dependencies, across the kernel transition.
 
     As a key feature, this series includes support for preserving memfd file
     descriptors, which allows critical in-memory data, such as guest RAM or
     any other large memory region, to be maintained in RAM across the kexec
     reboot.
 
   Mike Rappaport merits a mention here, for his extensive review and
   testing work.
 
 - The 3 patch series "kexec: reorganize kexec and kdump sysfs" from
   Sourabh Jain moves the kexec and kdump sysfs entries from /sys/kernel/
   to /sys/kernel/kexec/ and adds back-compatibility symlinks which can
   hopefully be removed one day.
 
 - The 2 patch series "kho: fixes for vmalloc restoration" from Mike
   Rapoport fixes a BUG which was being hit during KHO restoration of
   vmalloc() regions.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaTSAkQAKCRDdBJ7gKXxA
 jrkiAP9QKfsRv46XZaM5raScjY1ayjP+gqb2rgt6BQ/gZvb2+wD/cPAYOR6BiX52
 n0pVpQmG5P/KyOmpLztn96ejL4heKwQ=
 =JY96
 -----END PGP SIGNATURE-----

Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

* tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits)
  calibrate: update header inclusion
  Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()"
  vmcoreinfo: track and log recoverable hardware errors
  kho: fix restoring of contiguous ranges of order-0 pages
  kho: kho_restore_vmalloc: fix initialization of pages array
  MAINTAINERS: TPM DEVICE DRIVER: update the W-tag
  init: replace simple_strtoul with kstrtoul to improve lpj_setup
  KHO: fix boot failure due to kmemleak access to non-PRESENT pages
  Documentation/ABI: new kexec and kdump sysfs interface
  Documentation/ABI: mark old kexec sysfs deprecated
  kexec: move sysfs entries to /sys/kernel/kexec
  test_kho: always print restore status
  kho: free chunks using free_page() instead of kfree()
  selftests/liveupdate: add kexec test for multiple and empty sessions
  selftests/liveupdate: add simple kexec-based selftest for LUO
  selftests/liveupdate: add userspace API selftests
  docs: add documentation for memfd preservation via LUO
  mm: memfd_luo: allow preserving memfd
  liveupdate: luo_file: add private argument to store runtime state
  mm: shmem: export some functions to internal.h
  ...
2025-12-06 14:01:20 -08:00
Linus Torvalds
4b9d25b4d3 vfs-6.19-rc1.fixes
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaTLXbgAKCRCRxhvAZXjc
 og6oAP9QnawWV/g0vFt8O+jODb/JE54A6Vdb3Ai5Pt+yEB6iVgD/Reu8OhB694tO
 6j8j+lfPV35Z432VirfeKU7Vd4GUSwg=
 =HMln
 -----END PGP SIGNATURE-----

Merge tag 'vfs-6.19-rc1.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs fixes from Christian Brauner:

 - Fix a type conversion bug in the ipc subsystem

 - Fix per-dentry timeout warning in autofs

 - Drop the fd conversion from sockets

 - Move assert from iput_not_last() to iput()

 - Fix reversed check in filesystems_freeze_callback()

 - Use proper uapi types for new struct delegation definitions

* tag 'vfs-6.19-rc1.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  vfs: use UAPI types for new struct delegation definition
  mqueue: correct the type of ro to int
  Revert "net/socket: convert sock_map_fd() to FD_ADD()"
  autofs: fix per-dentry timeout warning
  fs: assert on I_FREEING not being set in iput() and iput_not_last()
  fs: PM: Fix reverse check in filesystems_freeze_callback()
2025-12-05 15:52:30 -08:00
Linus Torvalds
7cd122b552 Some filesystems use a kinda-sorta controlled dentry refcount leak to pin
dentries of created objects in dcache (and undo it when removing those).
 Reference is grabbed and not released, but it's not actually _stored_
 anywhere.  That works, but it's hard to follow and verify; among other
 things, we have no way to tell _which_ of the increments is intended
 to be an unpaired one.  Worse, on removal we need to decide whether
 the reference had already been dropped, which can be non-trivial if
 that removal is on umount and we need to figure out if this dentry is
 pinned due to e.g. unlink() not done.  Usually that is handled by using
 kill_litter_super() as ->kill_sb(), but there are open-coded special
 cases of the same (consider e.g. /proc/self).
 
 Things get simpler if we introduce a new dentry flag (DCACHE_PERSISTENT)
 marking those "leaked" dentries.  Having it set claims responsibility
 for +1 in refcount.
 
 The end result this series is aiming for:
 
 * get these unbalanced dget() and dput() replaced with new primitives that
   would, in addition to adjusting refcount, set and clear persistency flag.
 * instead of having kill_litter_super() mess with removing the remaining
   "leaked" references (e.g. for all tmpfs files that hadn't been removed
   prior to umount), have the regular shrink_dcache_for_umount() strip
   DCACHE_PERSISTENT of all dentries, dropping the corresponding
   reference if it had been set.  After that kill_litter_super() becomes
   an equivalent of kill_anon_super().
 
 Doing that in a single step is not feasible - it would affect too many places
 in too many filesystems.  It has to be split into a series.
 
 This work has really started early in 2024; quite a few preliminary pieces
 have already gone into mainline.  This chunk is finally getting to the
 meat of that stuff - infrastructure and most of the conversions to it.
 
 Some pieces are still sitting in the local branches, but the bulk of
 that stuff is here.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCaTEq1wAKCRBZ7Krx/gZQ
 643uAQC1rRslhw5l7OjxEpIYbGG4M+QaadN4Nf5Sr2SuTRaPJQD/W4oj/u4C2eCw
 Dd3q071tqyvm/PXNgN2EEnIaxlFUlwc=
 =rKq+
 -----END PGP SIGNATURE-----

Merge tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

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

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

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

  The end result this series is aiming for:

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

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

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

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

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

* tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
  d_make_discardable(): warn if given a non-persistent dentry
  kill securityfs_recursive_remove()
  convert securityfs
  get rid of kill_litter_super()
  convert rust_binderfs
  convert nfsctl
  convert rpc_pipefs
  convert hypfs
  hypfs: swich hypfs_create_u64() to returning int
  hypfs: switch hypfs_create_str() to returning int
  hypfs: don't pin dentries twice
  convert gadgetfs
  gadgetfs: switch to simple_remove_by_name()
  convert functionfs
  functionfs: switch to simple_remove_by_name()
  functionfs: fix the open/removal races
  functionfs: need to cancel ->reset_work in ->kill_sb()
  functionfs: don't bother with ffs->ref in ffs_data_{opened,closed}()
  functionfs: don't abuse ffs_data_closed() on fs shutdown
  convert selinuxfs
  ...
2025-12-05 14:36:21 -08:00
Edward Adam Davis
8cf01d0c43
mqueue: correct the type of ro to int
The ro variable, being of type bool, caused the -EROFS return value from
mnt_want_write() to be implicitly converted to 1. This prevented the file
from being correctly acquired, thus triggering the issue reported by
syzbot [1].

Changing the type of ro to int allows the system to correctly identify
the reason for the file open failure.

[1]
KASAN: null-ptr-deref in range [0x0000000000000040-0x0000000000000047]
Call Trace:
 do_mq_open+0x5a0/0x770 ipc/mqueue.c:932
 __do_sys_mq_open ipc/mqueue.c:945 [inline]
 __se_sys_mq_open ipc/mqueue.c:938 [inline]
 __x64_sys_mq_open+0x16a/0x1c0 ipc/mqueue.c:938

Fixes: f2573685bd ("ipc: convert do_mq_open() to FD_ADD()")
Reported-by: syzbot+40f42779048f7476e2e0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=40f42779048f7476e2e0
Tested-by: syzbot+40f42779048f7476e2e0@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Link: https://patch.msgid.link/tencent_369728EA76ED36CD98793A6D942C956C4C0A@qq.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-12-05 13:57:39 +01:00
Linus Torvalds
1b5dd29869 vfs-6.19-rc1.fd_prepare.fs
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaSmOZwAKCRCRxhvAZXjc
 op0AAP4oNVJkFyvgKoPos5K2EGFB8M7merGhpYtsOoeg8UK6OwD/UySQErHsXQDR
 sUDDa5uFOhfrkcfM8REtAN4wF8p5qAc=
 =QgFD
 -----END PGP SIGNATURE-----

Merge tag 'vfs-6.19-rc1.fd_prepare.fs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull fd prepare updates from Christian Brauner:
 "This adds the FD_ADD() and FD_PREPARE() primitive. They simplify the
  common pattern of get_unused_fd_flags() + create file + fd_install()
  that is used extensively throughout the kernel and currently requires
  cumbersome cleanup paths.

  FD_ADD() - For simple cases where a file is installed immediately:

      fd = FD_ADD(O_CLOEXEC, vfio_device_open_file(device));
      if (fd < 0)
          vfio_device_put_registration(device);
      return fd;

  FD_PREPARE() - For cases requiring access to the fd or file, or
  additional work before publishing:

      FD_PREPARE(fdf, O_CLOEXEC, sync_file->file);
      if (fdf.err) {
          fput(sync_file->file);
          return fdf.err;
      }

      data.fence = fd_prepare_fd(fdf);
      if (copy_to_user((void __user *)arg, &data, sizeof(data)))
          return -EFAULT;

      return fd_publish(fdf);

  The primitives are centered around struct fd_prepare. FD_PREPARE()
  encapsulates all allocation and cleanup logic and must be followed by
  a call to fd_publish() which associates the fd with the file and
  installs it into the caller's fdtable. If fd_publish() isn't called,
  both are deallocated automatically. FD_ADD() is a shorthand that does
  fd_publish() immediately and never exposes the struct to the caller.

  I've implemented this in a way that it's compatible with the cleanup
  infrastructure while also being usable separately. IOW, it's centered
  around struct fd_prepare which is aliased to class_fd_prepare_t and so
  we can make use of all the basica guard infrastructure"

* tag 'vfs-6.19-rc1.fd_prepare.fs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (42 commits)
  io_uring: convert io_create_mock_file() to FD_PREPARE()
  file: convert replace_fd() to FD_PREPARE()
  vfio: convert vfio_group_ioctl_get_device_fd() to FD_ADD()
  tty: convert ptm_open_peer() to FD_ADD()
  ntsync: convert ntsync_obj_get_fd() to FD_PREPARE()
  media: convert media_request_alloc() to FD_PREPARE()
  hv: convert mshv_ioctl_create_partition() to FD_ADD()
  gpio: convert linehandle_create() to FD_PREPARE()
  pseries: port papr_rtas_setup_file_interface() to FD_ADD()
  pseries: convert papr_platform_dump_create_handle() to FD_ADD()
  spufs: convert spufs_gang_open() to FD_PREPARE()
  papr-hvpipe: convert papr_hvpipe_dev_create_handle() to FD_PREPARE()
  spufs: convert spufs_context_open() to FD_PREPARE()
  net/socket: convert __sys_accept4_file() to FD_ADD()
  net/socket: convert sock_map_fd() to FD_ADD()
  net/kcm: convert kcm_ioctl() to FD_PREPARE()
  net/handshake: convert handshake_nl_accept_doit() to FD_PREPARE()
  secretmem: convert memfd_secret() to FD_ADD()
  memfd: convert memfd_create() to FD_ADD()
  bpf: convert bpf_token_create() to FD_PREPARE()
  ...
2025-12-01 17:32:07 -08:00
Linus Torvalds
a8058f8442 vfs-6.19-rc1.directory.locking
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaSmOZwAKCRCRxhvAZXjc
 op9tAQCJ//STOkvYHfqgsdRD+cW9MRg/gPzfVZgnV1FTyf8sMgEA0IsY5zCZB9eh
 9FdD0E57P8PlWRwWZ+LktnWBzRAUqwI=
 =MOVR
 -----END PGP SIGNATURE-----

Merge tag 'vfs-6.19-rc1.directory.locking' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull directory locking updates from Christian Brauner:
 "This contains the work to add centralized APIs for directory locking
  operations.

  This series is part of a larger effort to change directory operation
  locking to allow multiple concurrent operations in a directory. The
  ultimate goal is to lock the target dentry(s) rather than the whole
  parent directory.

  To help with changing the locking protocol, this series centralizes
  locking and lookup in new helper functions. The helpers establish a
  pattern where it is the dentry that is being locked and unlocked
  (currently the lock is held on dentry->d_parent->d_inode, but that can
  change in the future).

  This also changes vfs_mkdir() to unlock the parent on failure, as well
  as dput()ing the dentry. This allows end_creating() to only require
  the target dentry (which may be IS_ERR() after vfs_mkdir()), not the
  parent"

* tag 'vfs-6.19-rc1.directory.locking' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  nfsd: fix end_creating() conversion
  VFS: introduce end_creating_keep()
  VFS: change vfs_mkdir() to unlock on failure.
  ecryptfs: use new start_creating/start_removing APIs
  Add start_renaming_two_dentries()
  VFS/ovl/smb: introduce start_renaming_dentry()
  VFS/nfsd/ovl: introduce start_renaming() and end_renaming()
  VFS: add start_creating_killable() and start_removing_killable()
  VFS: introduce start_removing_dentry()
  smb/server: use end_removing_noperm for for target of smb2_create_link()
  VFS: introduce start_creating_noperm() and start_removing_noperm()
  VFS/nfsd/cachefiles/ovl: introduce start_removing() and end_removing()
  VFS/nfsd/cachefiles/ovl: add start_creating() and end_creating()
  VFS: tidy up do_unlinkat()
  VFS: introduce start_dirop() and end_dirop()
  debugfs: rename end_creating() to debugfs_end_creating()
2025-12-01 16:13:46 -08:00
Christian Brauner
f2573685bd
ipc: convert do_mq_open() to FD_ADD()
Christian Brauner <brauner@kernel.org> says:

The fix sent in [1] was squashed into this commit.

Fixes: https://lore.kernel.org/c41de645-8234-465f-a3be-f0385e3a163c@sirena.org.uk [1]
Reported-by: Mark Brown <broonie@kernel.org> [1]
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> [1]
Link: https://patch.msgid.link/20251123-work-fd-prepare-v4-22-b6efa1706cfd@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-28 12:42:33 +01:00
Al Viro
1e508e05dd convert mqueue
All modifications via normal VFS codepaths; just take care of making
persistent in in mqueue_create_attr() and discardable in mqueue_unlink()
and it doesn't need kill_litter_super() at all.

mqueue_unlink() side is best handled by having it call simple_unlink()
rather than duplicating its guts...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-11-16 01:35:02 -05:00
NeilBrown
fe497f0759
VFS: change vfs_mkdir() to unlock on failure.
vfs_mkdir() already drops the reference to the dentry on failure but it
leaves the parent locked.
This complicates end_creating() which needs to unlock the parent even
though the dentry is no longer available.

If we change vfs_mkdir() to unlock on failure as well as releasing the
dentry, we can remove the "parent" arg from end_creating() and simplify
the rules for calling it.

Note that cachefiles_get_directory() can choose to substitute an error
instead of actually calling vfs_mkdir(), for fault injection.  In that
case it needs to call end_creating(), just as vfs_mkdir() now does on
error.

ovl_create_real() will now unlock on error.  So the conditional
end_creating() after the call is removed, and end_creating() is called
internally on error.

Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: syzbot@syzkaller.appspotmail.com
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20251113002050.676694-15-neilb@ownmail.net
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-14 13:15:58 +01:00
NeilBrown
c9ba789dad
VFS: introduce start_creating_noperm() and start_removing_noperm()
xfs, fuse, ipc/mqueue need variants of start_creating or start_removing
which do not check permissions.
This patch adds _noperm versions of these functions.

Note that do_mq_open() was only calling mntget() so it could call
path_put() - it didn't really need an extra reference on the mnt.
Now it doesn't call mntget() and uses end_creating() which does
the dput() half of path_put().

Also mq_unlink() previously passed
   d_inode(dentry->d_parent)
as the dir inode to vfs_unlink().  This is after locking
   d_inode(mnt->mnt_root)
These two inodes are the same, but normally calls use the textual
parent.
So I've changes the vfs_unlink() call to be given d_inode(mnt->mnt_root).

Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neil@brown.name>

--
changes since v2:
 - dir arg passed to vfs_unlink() in mq_unlink() changed to match
   the dir passed to lookup_noperm()
 - restore assignment to path->mnt even though the mntget() is removed.

Link: https://patch.msgid.link/20251113002050.676694-7-neilb@ownmail.net
Tested-by: syzbot@syzkaller.appspotmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-14 13:15:56 +01:00
Vlad Kulikov
7229d74e5e ipc: create_ipc_ns: drop mqueue mount on sysctl setup failure
If setup_mq_sysctls(ns) fails after mq_init_ns(ns) succeeds, the error
path skipped releasing the internal kernel mqueue mount kept in
ns->mq_mnt. That leaves the vfsmount/superblock referenced until final
namespace teardown, i.e. a resource leak on this rare failure edge.

Unwind it by calling mntput(ns->mq_mnt) before dropping user_ns and
freeing the IPC namespace. This mirrors the normal ordering used in
free_ipc_ns().

Link: https://lkml.kernel.org/r/20251021181341.670297-1-vlad_kulikov_c@pm.me
Signed-off-by: Vlad Kulikov <vlad_kulikov_c@pm.me>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Ma Wupeng <mawupeng1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-12 10:00:15 -08:00
Christian Brauner
c2bbd2db52
ns: drop custom reference count initialization for initial namespaces
Initial namespaces don't modify their reference count anymore.
They remain fixed at one so drop the custom refcount initializations.

Link: https://patch.msgid.link/20251110-work-namespace-nstree-fixes-v1-16-e8a9264e0fb9@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-11 10:01:32 +01:00
Christian Brauner
3826d5dd06
ipc: enable is_ns_init_id() assertions
The ipc namespace may call put_ipc_ns() and get_ipc_ns() before it is
added to the namespace tree. Assign the id early like we do for a some
other namespaces.

Link: https://patch.msgid.link/20251110-work-namespace-nstree-fixes-v1-11-e8a9264e0fb9@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-11 10:01:31 +01:00
Christian Brauner
0b1765830c
ns: use NS_COMMON_INIT() for all namespaces
Now that we have a common initializer use it for all static namespaces.

Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-03 17:41:16 +01:00
Linus Torvalds
18b19abc37 namespace-6.18-rc1
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaNZQgQAKCRCRxhvAZXjc
 oiFXAQCpbLvkWbld9wLgxUBhq+q+kw5NvGxzpvqIhXwJB9F9YAEA44/Wevln4xGx
 +kRUbP+xlRQqenIYs2dLzVHzAwAdfQ4=
 =EO4Y
 -----END PGP SIGNATURE-----

Merge tag 'namespace-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

* tag 'namespace-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (65 commits)
  ns: drop assert
  ns: move ns type into struct ns_common
  nstree: make struct ns_tree private
  ns: add ns_debug()
  ns: simplify ns_common_init() further
  cgroup: add missing ns_common include
  ns: use inode initializer for initial namespaces
  selftests/namespaces: verify initial namespace inode numbers
  ns: rename to __ns_ref
  nsfs: port to ns_ref_*() helpers
  net: port to ns_ref_*() helpers
  uts: port to ns_ref_*() helpers
  ipv4: use check_net()
  net: use check_net()
  net-sysfs: use check_net()
  user: port to ns_ref_*() helpers
  time: port to ns_ref_*() helpers
  pid: port to ns_ref_*() helpers
  ipc: port to ns_ref_*() helpers
  cgroup: port to ns_ref_*() helpers
  ...
2025-09-29 11:20:29 -07:00
Christian Brauner
4055526d35
ns: move ns type into struct ns_common
It's misplaced in struct proc_ns_operations and ns->ops might be NULL if
the namespace is compiled out but we still want to know the type of the
namespace for the initial namespace struct.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-25 09:23:54 +02:00
Christian Brauner
d7610cb745 ns: simplify ns_common_init() further
Simply derive the ns operations from the namespace type.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-22 14:47:10 +02:00
Christian Brauner
7cf7303211
ns: use inode initializer for initial namespaces
Just use the common helper we have.

Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19 16:22:38 +02:00