Commit Graph

2449 Commits

Author SHA1 Message Date
Linus Torvalds
8f6f76a6a2 Merge tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
 "As usual, lots of singleton and doubleton patches all over the tree
  and there's little I can say which isn't in the individual changelogs.

  The lengthier patch series are

   - 'kdump: use generic functions to simplify crashkernel reservation
     in arch', from Baoquan He. This is mainly cleanups and
     consolidation of the 'crashkernel=' kernel parameter handling

   - After much discussion, David Laight's 'minmax: Relax type checks in
     min() and max()' is here. Hopefully reduces some typecasting and
     the use of min_t() and max_t()

   - A group of patches from Oleg Nesterov which clean up and slightly
     fix our handling of reads from /proc/PID/task/... and which remove
     task_struct.thread_group"

* tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (64 commits)
  scripts/gdb/vmalloc: disable on no-MMU
  scripts/gdb: fix usage of MOD_TEXT not defined when CONFIG_MODULES=n
  .mailmap: add address mapping for Tomeu Vizoso
  mailmap: update email address for Claudiu Beznea
  tools/testing/selftests/mm/run_vmtests.sh: lower the ptrace permissions
  .mailmap: map Benjamin Poirier's address
  scripts/gdb: add lx_current support for riscv
  ocfs2: fix a spelling typo in comment
  proc: test ProtectionKey in proc-empty-vm test
  proc: fix proc-empty-vm test with vsyscall
  fs/proc/base.c: remove unneeded semicolon
  do_io_accounting: use sig->stats_lock
  do_io_accounting: use __for_each_thread()
  ocfs2: replace BUG_ON() at ocfs2_num_free_extents() with ocfs2_error()
  ocfs2: fix a typo in a comment
  scripts/show_delta: add __main__ judgement before main code
  treewide: mark stuff as __ro_after_init
  fs: ocfs2: check status values
  proc: test /proc/${pid}/statm
  compiler.h: move __is_constexpr() to compiler.h
  ...
2023-11-02 20:53:31 -10:00
Linus Torvalds
ecae0bd517 Merge tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
 "Many singleton patches against the MM code. The patch series which are
  included in this merge do the following:

   - Kemeng Shi has contributed some compation maintenance work in the
     series 'Fixes and cleanups to compaction'

   - Joel Fernandes has a patchset ('Optimize mremap during mutual
     alignment within PMD') which fixes an obscure issue with mremap()'s
     pagetable handling during a subsequent exec(), based upon an
     implementation which Linus suggested

   - More DAMON/DAMOS maintenance and feature work from SeongJae Park i
     the following patch series:

	mm/damon: misc fixups for documents, comments and its tracepoint
	mm/damon: add a tracepoint for damos apply target regions
	mm/damon: provide pseudo-moving sum based access rate
	mm/damon: implement DAMOS apply intervals
	mm/damon/core-test: Fix memory leaks in core-test
	mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval

   - In the series 'Do not try to access unaccepted memory' Adrian
     Hunter provides some fixups for the recently-added 'unaccepted
     memory' feature. To increase the feature's checking coverage. 'Plug
     a few gaps where RAM is exposed without checking if it is
     unaccepted memory'

   - In the series 'cleanups for lockless slab shrink' Qi Zheng has done
     some maintenance work which is preparation for the lockless slab
     shrinking code

   - Qi Zheng has redone the earlier (and reverted) attempt to make slab
     shrinking lockless in the series 'use refcount+RCU method to
     implement lockless slab shrink'

   - David Hildenbrand contributes some maintenance work for the rmap
     code in the series 'Anon rmap cleanups'

   - Kefeng Wang does more folio conversions and some maintenance work
     in the migration code. Series 'mm: migrate: more folio conversion
     and unification'

   - Matthew Wilcox has fixed an issue in the buffer_head code which was
     causing long stalls under some heavy memory/IO loads. Some cleanups
     were added on the way. Series 'Add and use bdev_getblk()'

   - In the series 'Use nth_page() in place of direct struct page
     manipulation' Zi Yan has fixed a potential issue with the direct
     manipulation of hugetlb page frames

   - In the series 'mm: hugetlb: Skip initialization of gigantic tail
     struct pages if freed by HVO' has improved our handling of gigantic
     pages in the hugetlb vmmemmep optimizaton code. This provides
     significant boot time improvements when significant amounts of
     gigantic pages are in use

   - Matthew Wilcox has sent the series 'Small hugetlb cleanups' - code
     rationalization and folio conversions in the hugetlb code

   - Yin Fengwei has improved mlock()'s handling of large folios in the
     series 'support large folio for mlock'

   - In the series 'Expose swapcache stat for memcg v1' Liu Shixin has
     added statistics for memcg v1 users which are available (and
     useful) under memcg v2

   - Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
     prctl so that userspace may direct the kernel to not automatically
     propagate the denial to child processes. The series is named 'MDWE
     without inheritance'

   - Kefeng Wang has provided the series 'mm: convert numa balancing
     functions to use a folio' which does what it says

   - In the series 'mm/ksm: add fork-exec support for prctl' Stefan
     Roesch makes is possible for a process to propagate KSM treatment
     across exec()

   - Huang Ying has enhanced memory tiering's calculation of memory
     distances. This is used to permit the dax/kmem driver to use 'high
     bandwidth memory' in addition to Optane Data Center Persistent
     Memory Modules (DCPMM). The series is named 'memory tiering:
     calculate abstract distance based on ACPI HMAT'

   - In the series 'Smart scanning mode for KSM' Stefan Roesch has
     optimized KSM by teaching it to retain and use some historical
     information from previous scans

   - Yosry Ahmed has fixed some inconsistencies in memcg statistics in
     the series 'mm: memcg: fix tracking of pending stats updates
     values'

   - In the series 'Implement IOCTL to get and optionally clear info
     about PTEs' Peter Xu has added an ioctl to /proc/<pid>/pagemap
     which permits us to atomically read-then-clear page softdirty
     state. This is mainly used by CRIU

   - Hugh Dickins contributed the series 'shmem,tmpfs: general
     maintenance', a bunch of relatively minor maintenance tweaks to
     this code

   - Matthew Wilcox has increased the use of the VMA lock over
     file-backed page faults in the series 'Handle more faults under the
     VMA lock'. Some rationalizations of the fault path became possible
     as a result

   - In the series 'mm/rmap: convert page_move_anon_rmap() to
     folio_move_anon_rmap()' David Hildenbrand has implemented some
     cleanups and folio conversions

   - In the series 'various improvements to the GUP interface' Lorenzo
     Stoakes has simplified and improved the GUP interface with an eye
     to providing groundwork for future improvements

   - Andrey Konovalov has sent along the series 'kasan: assorted fixes
     and improvements' which does those things

   - Some page allocator maintenance work from Kemeng Shi in the series
     'Two minor cleanups to break_down_buddy_pages'

   - In thes series 'New selftest for mm' Breno Leitao has developed
     another MM self test which tickles a race we had between madvise()
     and page faults

   - In the series 'Add folio_end_read' Matthew Wilcox provides cleanups
     and an optimization to the core pagecache code

   - Nhat Pham has added memcg accounting for hugetlb memory in the
     series 'hugetlb memcg accounting'

   - Cleanups and rationalizations to the pagemap code from Lorenzo
     Stoakes, in the series 'Abstract vma_merge() and split_vma()'

   - Audra Mitchell has fixed issues in the procfs page_owner code's new
     timestamping feature which was causing some misbehaviours. In the
     series 'Fix page_owner's use of free timestamps'

   - Lorenzo Stoakes has fixed the handling of new mappings of sealed
     files in the series 'permit write-sealed memfd read-only shared
     mappings'

   - Mike Kravetz has optimized the hugetlb vmemmap optimization in the
     series 'Batch hugetlb vmemmap modification operations'

   - Some buffer_head folio conversions and cleanups from Matthew Wilcox
     in the series 'Finish the create_empty_buffers() transition'

   - As a page allocator performance optimization Huang Ying has added
     automatic tuning to the allocator's per-cpu-pages feature, in the
     series 'mm: PCP high auto-tuning'

   - Roman Gushchin has contributed the patchset 'mm: improve
     performance of accounted kernel memory allocations' which improves
     their performance by ~30% as measured by a micro-benchmark

   - folio conversions from Kefeng Wang in the series 'mm: convert page
     cpupid functions to folios'

   - Some kmemleak fixups in Liu Shixin's series 'Some bugfix about
     kmemleak'

   - Qi Zheng has improved our handling of memoryless nodes by keeping
     them off the allocation fallback list. This is done in the series
     'handle memoryless nodes more appropriately'

   - khugepaged conversions from Vishal Moola in the series 'Some
     khugepaged folio conversions'"

[ bcachefs conflicts with the dynamically allocated shrinkers have been
  resolved as per Stephen Rothwell in

     https://lore.kernel.org/all/20230913093553.4290421e@canb.auug.org.au/

  with help from Qi Zheng.

  The clone3 test filtering conflict was half-arsed by yours truly ]

* tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (406 commits)
  mm/damon/sysfs: update monitoring target regions for online input commit
  mm/damon/sysfs: remove requested targets when online-commit inputs
  selftests: add a sanity check for zswap
  Documentation: maple_tree: fix word spelling error
  mm/vmalloc: fix the unchecked dereference warning in vread_iter()
  zswap: export compression failure stats
  Documentation: ubsan: drop "the" from article title
  mempolicy: migration attempt to match interleave nodes
  mempolicy: mmap_lock is not needed while migrating folios
  mempolicy: alloc_pages_mpol() for NUMA policy without vma
  mm: add page_rmappable_folio() wrapper
  mempolicy: remove confusing MPOL_MF_LAZY dead code
  mempolicy: mpol_shared_policy_init() without pseudo-vma
  mempolicy trivia: use pgoff_t in shared mempolicy tree
  mempolicy trivia: slightly more consistent naming
  mempolicy trivia: delete those ancient pr_debug()s
  mempolicy: fix migrate_pages(2) syscall return nr_failed
  kernfs: drop shared NUMA mempolicy hooks
  hugetlbfs: drop shared NUMA mempolicy pretence
  mm/damon/sysfs-test: add a unit test for damon_sysfs_set_targets()
  ...
2023-11-02 19:38:47 -10:00
Linus Torvalds
426ee5196d Merge tag 'sysctl-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull sysctl updates from Luis Chamberlain:
 "To help make the move of sysctls out of kernel/sysctl.c not incur a
  size penalty sysctl has been changed to allow us to not require the
  sentinel, the final empty element on the sysctl array. Joel Granados
  has been doing all this work. On the v6.6 kernel we got the major
  infrastructure changes required to support this. For v6.7-rc1 we have
  all arch/ and drivers/ modified to remove the sentinel. Both arch and
  driver changes have been on linux-next for a bit less than a month. It
  is worth re-iterating the value:

   - this helps reduce the overall build time size of the kernel and run
     time memory consumed by the kernel by about ~64 bytes per array

   - the extra 64-byte penalty is no longer inncurred now when we move
     sysctls out from kernel/sysctl.c to their own files

  For v6.8-rc1 expect removal of all the sentinels and also then the
  unneeded check for procname == NULL.

  The last two patches are fixes recently merged by Krister Johansen
  which allow us again to use softlockup_panic early on boot. This used
  to work but the alias work broke it. This is useful for folks who want
  to detect softlockups super early rather than wait and spend money on
  cloud solutions with nothing but an eventual hung kernel. Although
  this hadn't gone through linux-next it's also a stable fix, so we
  might as well roll through the fixes now"

* tag 'sysctl-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (23 commits)
  watchdog: move softlockup_panic back to early_param
  proc: sysctl: prevent aliased sysctls from getting passed to init
  intel drm: Remove now superfluous sentinel element from ctl_table array
  Drivers: hv: Remove now superfluous sentinel element from ctl_table array
  raid: Remove now superfluous sentinel element from ctl_table array
  fw loader: Remove the now superfluous sentinel element from ctl_table array
  sgi-xp: Remove the now superfluous sentinel element from ctl_table array
  vrf: Remove the now superfluous sentinel element from ctl_table array
  char-misc: Remove the now superfluous sentinel element from ctl_table array
  infiniband: Remove the now superfluous sentinel element from ctl_table array
  macintosh: Remove the now superfluous sentinel element from ctl_table array
  parport: Remove the now superfluous sentinel element from ctl_table array
  scsi: Remove now superfluous sentinel element from ctl_table array
  tty: Remove now superfluous sentinel element from ctl_table array
  xen: Remove now superfluous sentinel element from ctl_table array
  hpet: Remove now superfluous sentinel element from ctl_table array
  c-sky: Remove now superfluous sentinel element from ctl_talbe array
  powerpc: Remove now superfluous sentinel element from ctl_table arrays
  riscv: Remove now superfluous sentinel element from ctl_table array
  x86/vdso: Remove now superfluous sentinel element from ctl_table array
  ...
2023-11-01 20:51:41 -10:00
Linus Torvalds
1b10d2c8c6 Merge tag 'bootconfig-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull bootconfig updates from Masami Hiramatsu:

 - Documentation update for /proc/cmdline, which includes both the
   parameters from bootloader and the embedded parameters in the kernel

 - fs/proc: Add bootloader argument as a comment line to
   /proc/bootconfig so that the user can distinguish what parameters
   were passed from bootloader even if bootconfig modified that

 - Documentation fix to add /proc/bootconfig to proc.rst

* tag 'bootconfig-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  doc: Add /proc/bootconfig to proc.rst
  fs/proc: Add boot loader arguments as comment to /proc/bootconfig
  doc: Update /proc/cmdline documentation to include boot config
2023-11-01 16:07:05 -10:00
Yang Li
639931020e fs/proc/base.c: remove unneeded semicolon
./fs/proc/base.c:3829:2-3: Unneeded semicolon

Link: https://lkml.kernel.org/r/20231026005634.6581-1-yang.lee@linux.alibaba.com
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=7057
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-11-01 12:46:59 -07:00
Oleg Nesterov
1df4bd83cd do_io_accounting: use sig->stats_lock
Rather than lock_task_sighand(), sig->stats_lock was specifically designed
for this type of use.

This way the "if (whole)" branch runs lockless in the likely case.

Link: https://lkml.kernel.org/r/20231023153405.GA4639@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-11-01 12:46:59 -07:00
Oleg Nesterov
2320222067 do_io_accounting: use __for_each_thread()
Rather than while_each_thread() which should be avoided when possible.

This makes the code more clear and allows the next change.

Link: https://lkml.kernel.org/r/20231023153343.GA4629@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-11-01 12:46:58 -07:00
Krister Johansen
8b793bcda6 watchdog: move softlockup_panic back to early_param
Setting softlockup_panic from do_sysctl_args() causes it to take effect
later in boot.  The lockup detector is enabled before SMP is brought
online, but do_sysctl_args runs afterwards.  If a user wants to set
softlockup_panic on boot and have it trigger should a softlockup occur
during onlining of the non-boot processors, they could do this prior to
commit f117955a22 ("kernel/watchdog.c: convert {soft/hard}lockup boot
parameters to sysctl aliases").  However, after this commit the value
of softlockup_panic is set too late to be of help for this type of
problem.  Restore the prior behavior.

Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Cc: stable@vger.kernel.org
Fixes: f117955a22 ("kernel/watchdog.c: convert {soft/hard}lockup boot parameters to sysctl aliases")
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-11-01 12:10:02 -07:00
Krister Johansen
8001f49394 proc: sysctl: prevent aliased sysctls from getting passed to init
The code that checks for unknown boot options is unaware of the sysctl
alias facility, which maps bootparams to sysctl values.  If a user sets
an old value that has a valid alias, a message about an invalid
parameter will be printed during boot, and the parameter will get passed
to init.  Fix by checking for the existence of aliased parameters in the
unknown boot parameter code.  If an alias exists, don't return an error
or pass the value to init.

Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Cc: stable@vger.kernel.org
Fixes: 0a477e1ae2 ("kernel/sysctl: support handling command line aliases")
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-11-01 12:10:02 -07:00
Linus Torvalds
14ab6d425e Merge tag 'vfs-6.7.ctime' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs
Pull vfs inode time accessor updates from Christian Brauner:
 "This finishes the conversion of all inode time fields to accessor
  functions as discussed on list. Changing timestamps manually as we
  used to do before is error prone. Using accessors function makes this
  robust.

  It does not contain the switch of the time fields to discrete 64 bit
  integers to replace struct timespec and free up space in struct inode.
  But after this, the switch can be trivially made and the patch should
  only affect the vfs if we decide to do it"

* tag 'vfs-6.7.ctime' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (86 commits)
  fs: rename inode i_atime and i_mtime fields
  security: convert to new timestamp accessors
  selinux: convert to new timestamp accessors
  apparmor: convert to new timestamp accessors
  sunrpc: convert to new timestamp accessors
  mm: convert to new timestamp accessors
  bpf: convert to new timestamp accessors
  ipc: convert to new timestamp accessors
  linux: convert to new timestamp accessors
  zonefs: convert to new timestamp accessors
  xfs: convert to new timestamp accessors
  vboxsf: convert to new timestamp accessors
  ufs: convert to new timestamp accessors
  udf: convert to new timestamp accessors
  ubifs: convert to new timestamp accessors
  tracefs: convert to new timestamp accessors
  sysv: convert to new timestamp accessors
  squashfs: convert to new timestamp accessors
  server: convert to new timestamp accessors
  client: convert to new timestamp accessors
  ...
2023-10-30 09:47:13 -10:00
Linus Torvalds
3b3f874cc1 Merge tag 'vfs-6.7.misc' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
 "This contains the usual miscellaneous features, cleanups, and fixes
  for vfs and individual fses.

  Features:

   - Rename and export helpers that get write access to a mount. They
     are used in overlayfs to get write access to the upper mount.

   - Print the pretty name of the root device on boot failure. This
     helps in scenarios where we would usually only print
     "unknown-block(1,2)".

   - Add an internal SB_I_NOUMASK flag. This is another part in the
     endless POSIX ACL saga in a way.

     When POSIX ACLs are enabled via SB_POSIXACL the vfs cannot strip
     the umask because if the relevant inode has POSIX ACLs set it might
     take the umask from there. But if the inode doesn't have any POSIX
     ACLs set then we apply the umask in the filesytem itself. So we end
     up with:

      (1) no SB_POSIXACL -> strip umask in vfs
      (2) SB_POSIXACL    -> strip umask in filesystem

     The umask semantics associated with SB_POSIXACL allowed filesystems
     that don't even support POSIX ACLs at all to raise SB_POSIXACL
     purely to avoid umask stripping. That specifically means NFS v4 and
     Overlayfs. NFS v4 does it because it delegates this to the server
     and Overlayfs because it needs to delegate umask stripping to the
     upper filesystem, i.e., the filesystem used as the writable layer.

     This went so far that SB_POSIXACL is raised eve on kernels that
     don't even have POSIX ACL support at all.

     Stop this blatant abuse and add SB_I_NOUMASK which is an internal
     superblock flag that filesystems can raise to opt out of umask
     handling. That should really only be the two mentioned above. It's
     not that we want any filesystems to do this. Ideally we have all
     umask handling always in the vfs.

   - Make overlayfs use SB_I_NOUMASK too.

   - Now that we have SB_I_NOUMASK, stop checking for SB_POSIXACL in
     IS_POSIXACL() if the kernel doesn't have support for it. This is a
     very old patch but it's only possible to do this now with the wider
     cleanup that was done.

   - Follow-up work on fake path handling from last cycle. Citing mostly
     from Amir:

     When overlayfs was first merged, overlayfs files of regular files
     and directories, the ones that are installed in file table, had a
     "fake" path, namely, f_path is the overlayfs path and f_inode is
     the "real" inode on the underlying filesystem.

     In v6.5, we took another small step by introducing of the
     backing_file container and the file_real_path() helper. This change
     allowed vfs and filesystem code to get the "real" path of an
     overlayfs backing file. With this change, we were able to make
     fsnotify work correctly and report events on the "real" filesystem
     objects that were accessed via overlayfs.

     This method works fine, but it still leaves the vfs vulnerable to
     new code that is not aware of files with fake path. A recent
     example is commit db1d1e8b98 ("IMA: use vfs_getattr_nosec to get
     the i_version"). This commit uses direct referencing to f_path in
     IMA code that otherwise uses file_inode() and file_dentry() to
     reference the filesystem objects that it is measuring.

     This contains work to switch things around: instead of having
     filesystem code opt-in to get the "real" path, have generic code
     opt-in for the "fake" path in the few places that it is needed.

     Is it far more likely that new filesystems code that does not use
     the file_dentry() and file_real_path() helpers will end up causing
     crashes or averting LSM/audit rules if we keep the "fake" path
     exposed by default.

     This change already makes file_dentry() moot, but for now we did
     not change this helper just added a WARN_ON() in ovl_d_real() to
     catch if we have made any wrong assumptions.

     After the dust settles on this change, we can make file_dentry() a
     plain accessor and we can drop the inode argument to ->d_real().

   - Switch struct file to SLAB_TYPESAFE_BY_RCU. This looks like a small
     change but it really isn't and I would like to see everyone on
     their tippie toes for any possible bugs from this work.

     Essentially we've been doing most of what SLAB_TYPESAFE_BY_RCU for
     files since a very long time because of the nasty interactions
     between the SCM_RIGHTS file descriptor garbage collection. So
     extending it makes a lot of sense but it is a subtle change. There
     are almost no places that fiddle with file rcu semantics directly
     and the ones that did mess around with struct file internal under
     rcu have been made to stop doing that because it really was always
     dodgy.

     I forgot to put in the link tag for this change and the discussion
     in the commit so adding it into the merge message:

       https://lore.kernel.org/r/20230926162228.68666-1-mjguzik@gmail.com

  Cleanups:

   - Various smaller pipe cleanups including the removal of a spin lock
     that was only used to protect against writes without pipe_lock()
     from O_NOTIFICATION_PIPE aka watch queues. As that was never
     implemented remove the additional locking from pipe_write().

   - Annotate struct watch_filter with the new __counted_by attribute.

   - Clarify do_unlinkat() cleanup so that it doesn't look like an extra
     iput() is done that would cause issues.

   - Simplify file cleanup when the file has never been opened.

   - Use module helper instead of open-coding it.

   - Predict error unlikely for stale retry.

   - Use WRITE_ONCE() for mount expiry field instead of just commenting
     that one hopes the compiler doesn't get smart.

  Fixes:

   - Fix readahead on block devices.

   - Fix writeback when layztime is enabled and inodes whose timestamp
     is the only thing that changed reside on wb->b_dirty_time. This
     caused excessively large zombie memory cgroup when lazytime was
     enabled as such inodes weren't handled fast enough.

   - Convert BUG_ON() to WARN_ON_ONCE() in open_last_lookups()"

* tag 'vfs-6.7.misc' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (26 commits)
  file, i915: fix file reference for mmap_singleton()
  vfs: Convert BUG_ON to WARN_ON_ONCE in open_last_lookups
  writeback, cgroup: switch inodes with dirty timestamps to release dying cgwbs
  chardev: Simplify usage of try_module_get()
  ovl: rely on SB_I_NOUMASK
  fs: fix umask on NFS with CONFIG_FS_POSIX_ACL=n
  fs: store real path instead of fake path in backing file f_path
  fs: create helper file_user_path() for user displayed mapped file path
  fs: get mnt_writers count for an open backing file's real path
  vfs: stop counting on gcc not messing with mnt_expiry_mark if not asked
  vfs: predict the error in retry_estale as unlikely
  backing file: free directly
  vfs: fix readahead(2) on block devices
  io_uring: use files_lookup_fd_locked()
  file: convert to SLAB_TYPESAFE_BY_RCU
  vfs: shave work on failed file open
  fs: simplify misleading code to remove ambiguity regarding ihold()/iput()
  watch_queue: Annotate struct watch_filter with __counted_by
  fs/pipe: use spinlock in pipe_read() only if there is a watch_queue
  fs/pipe: remove unnecessary spinlock from pipe_write()
  ...
2023-10-30 09:14:19 -10:00
Hugh Dickins
ddc1a5cbc0 mempolicy: alloc_pages_mpol() for NUMA policy without vma
Shrink shmem's stack usage by eliminating the pseudo-vma from its folio
allocation.  alloc_pages_mpol(gfp, order, pol, ilx, nid) becomes the
principal actor for passing mempolicy choice down to __alloc_pages(),
rather than vma_alloc_folio(gfp, order, vma, addr, hugepage).

vma_alloc_folio() and alloc_pages() remain, but as wrappers around
alloc_pages_mpol().  alloc_pages_bulk_*() untouched, except to provide the
additional args to policy_nodemask(), which subsumes policy_node(). 
Cleanup throughout, cutting out some unhelpful "helpers".

It would all be much simpler without MPOL_INTERLEAVE, but that adds a
dynamic to the constant mpol: complicated by v3.6 commit 09c231cb8b
("tmpfs: distribute interleave better across nodes"), which added ino bias
to the interleave, hidden from mm/mempolicy.c until this commit.

Hence "ilx" throughout, the "interleave index".  Originally I thought it
could be done just with nid, but that's wrong: the nodemask may come from
the shared policy layer below a shmem vma, or it may come from the task
layer above a shmem vma; and without the final nodemask then nodeid cannot
be decided.  And how ilx is applied depends also on page order.

The interleave index is almost always irrelevant unless MPOL_INTERLEAVE:
with one exception in alloc_pages_mpol(), where the NO_INTERLEAVE_INDEX
passed down from vma-less alloc_pages() is also used as hint not to use
THP-style hugepage allocation - to avoid the overhead of a hugepage arg
(though I don't understand why we never just added a GFP bit for THP - if
it actually needs a different allocation strategy from other pages of the
same order).  vma_alloc_folio() still carries its hugepage arg here, but
it is not used, and should be removed when agreed.

get_vma_policy() no longer allows a NULL vma: over time I believe we've
eradicated all the places which used to need it e.g.  swapoff and madvise
used to pass NULL vma to read_swap_cache_async(), but now know the vma.

[hughd@google.com: handle NULL mpol being passed to __read_swap_cache_async()]
  Link: https://lkml.kernel.org/r/ea419956-4751-0102-21f7-9c93cb957892@google.com
Link: https://lkml.kernel.org/r/74e34633-6060-f5e3-aee-7040d43f2e93@google.com
Link: https://lkml.kernel.org/r/1738368e-bac0-fd11-ed7f-b87142a939fe@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tejun heo <tj@kernel.org>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Domenico Cerasuolo <mimmocerasuolo@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25 16:47:16 -07:00
Amir Goldstein
08582d678f fs: create helper file_user_path() for user displayed mapped file path
Overlayfs uses backing files with "fake" overlayfs f_path and "real"
underlying f_inode, in order to use underlying inode aops for mapped
files and to display the overlayfs path in /proc/<pid>/maps.

In preparation for storing the overlayfs "fake" path instead of the
underlying "real" path in struct backing_file, define a noop helper
file_user_path() that returns f_path for now.

Use the new helper in procfs and kernel logs whenever a path of a
mapped file is displayed to users.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20231009153712.1566422-3-amir73il@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-19 11:03:15 +02:00
Christian Brauner
0ede61d858 file: convert to SLAB_TYPESAFE_BY_RCU
In recent discussions around some performance improvements in the file
handling area we discussed switching the file cache to rely on
SLAB_TYPESAFE_BY_RCU which allows us to get rid of call_rcu() based
freeing for files completely. This is a pretty sensitive change overall
but it might actually be worth doing.

The main downside is the subtlety. The other one is that we should
really wait for Jann's patch to land that enables KASAN to handle
SLAB_TYPESAFE_BY_RCU UAFs. Currently it doesn't but a patch for this
exists.

With SLAB_TYPESAFE_BY_RCU objects may be freed and reused multiple times
which requires a few changes. So it isn't sufficient anymore to just
acquire a reference to the file in question under rcu using
atomic_long_inc_not_zero() since the file might have already been
recycled and someone else might have bumped the reference.

In other words, callers might see reference count bumps from newer
users. For this reason it is necessary to verify that the pointer is the
same before and after the reference count increment. This pattern can be
seen in get_file_rcu() and __files_get_rcu().

In addition, it isn't possible to access or check fields in struct file
without first aqcuiring a reference on it. Not doing that was always
very dodgy and it was only usable for non-pointer data in struct file.
With SLAB_TYPESAFE_BY_RCU it is necessary that callers first acquire a
reference under rcu or they must hold the files_lock of the fdtable.
Failing to do either one of this is a bug.

Thanks to Jann for pointing out that we need to ensure memory ordering
between reallocations and pointer check by ensuring that all subsequent
loads have a dependency on the second load in get_file_rcu() and
providing a fixup that was folded into this patch.

Cc: Jann Horn <jannh@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-19 11:02:48 +02:00
Alexey Dobriyan
ead5a72773 proc: save LOC by using while loop
Use while loop instead of infinite loop with "break;".

Also move some variable to the inner scope where they belong.

Link: https://lkml.kernel.org/r/82c8f8e7-8ded-46ca-8857-e60b991d6205@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18 14:43:22 -07:00
Alexey Dobriyan
860a2e7fa4 proc: use initializer for clearing some buffers
Save LOC by using dark magic of initialisation instead of memset().

Those buffer aren't passed to userspace directly so padding is not
an issue.

Link: https://lkml.kernel.org/r/3821d3a2-6e10-4629-b0d5-9519d828ab72@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18 14:43:22 -07:00
Muhammad Usama Anjum
12f6b01a0b fs/proc/task_mmu: add fast paths to get/clear PAGE_IS_WRITTEN flag
Adding fast code paths to handle specifically only get and/or clear
operation of PAGE_IS_WRITTEN, increases its performance by 0-35%.  The
results of some test cases are given below:

Test-case-1
t1 = (Get + WP) time
t2 = WP time
                       t1            t2
Without this patch:    140-170mcs    90-115mcs
With this patch:       110mcs        80mcs
Worst case diff:       35% faster    30% faster

Test-case-2
t3 = atomic Get and WP
                      t3
Without this patch:   120-140mcs
With this patch:      100-110mcs
Worst case diff:      21% faster

Link: https://lkml.kernel.org/r/20230821141518.870589-4-usama.anjum@collabora.com
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Miroslaw <emmir@google.com>
Cc: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Paul Gofman <pgofman@codeweavers.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yun Zhou <yun.zhou@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18 14:34:13 -07:00
Muhammad Usama Anjum
52526ca7fd fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs
The PAGEMAP_SCAN IOCTL on the pagemap file can be used to get or optionally
clear the info about page table entries. The following operations are
supported in this IOCTL:
- Scan the address range and get the memory ranges matching the provided
  criteria. This is performed when the output buffer is specified.
- Write-protect the pages. The PM_SCAN_WP_MATCHING is used to write-protect
  the pages of interest. The PM_SCAN_CHECK_WPASYNC aborts the operation if
  non-Async Write Protected pages are found. The ``PM_SCAN_WP_MATCHING``
  can be used with or without PM_SCAN_CHECK_WPASYNC.
- Both of those operations can be combined into one atomic operation where
  we can get and write protect the pages as well.

Following flags about pages are currently supported:
- PAGE_IS_WPALLOWED - Page has async-write-protection enabled
- PAGE_IS_WRITTEN - Page has been written to from the time it was write protected
- PAGE_IS_FILE - Page is file backed
- PAGE_IS_PRESENT - Page is present in the memory
- PAGE_IS_SWAPPED - Page is in swapped
- PAGE_IS_PFNZERO - Page has zero PFN
- PAGE_IS_HUGE - Page is THP or Hugetlb backed

This IOCTL can be extended to get information about more PTE bits. The
entire address range passed by user [start, end) is scanned until either
the user provided buffer is full or max_pages have been found.

[akpm@linux-foundation.org: update it for "mm: hugetlb: add huge page size param to set_huge_pte_at()"]
[akpm@linux-foundation.org: fix CONFIG_HUGETLB_PAGE=n warning]
[arnd@arndb.de: hide unused pagemap_scan_backout_range() function]
  Link: https://lkml.kernel.org/r/20230927060257.2975412-1-arnd@kernel.org
[sfr@canb.auug.org.au: fix "fs/proc/task_mmu: hide unused pagemap_scan_backout_range() function"]
  Link: https://lkml.kernel.org/r/20230928092223.0625c6bf@canb.auug.org.au
Link: https://lkml.kernel.org/r/20230821141518.870589-3-usama.anjum@collabora.com
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Andrei Vagin <avagin@gmail.com>
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Cc: Alex Sierra <alex.sierra@amd.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Miroslaw <emmir@google.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Paul Gofman <pgofman@codeweavers.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yun Zhou <yun.zhou@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18 14:34:12 -07:00
Jeff Layton
200d942170 proc: convert to new timestamp accessors
Convert to using the new inode timestamp accessor functions.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20231004185347.80880-59-jlayton@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-18 14:08:26 +02:00
Paul E. McKenney
717c7c894d fs/proc: Add boot loader arguments as comment to /proc/bootconfig
In kernels built with CONFIG_BOOT_CONFIG_FORCE=y, /proc/cmdline will
show all kernel boot parameters, both those supplied by the boot loader
and those embedded in the kernel image.  This works well for those who
just want to see all of the kernel boot parameters, but is not helpful to
those who need to see only those parameters supplied by the boot loader.
This is especially important when these parameters are presented to the
boot loader by automation that might gather them from diverse sources.
It is also useful when booting the next kernel via kexec(), in which
case it is necessary to supply only those kernel command-line arguments
from the boot loader, and most definitely not those that were embedded
into the current kernel.

Therefore, add comments to /proc/bootconfig of the form:

	# Parameters from bootloader:
	# root=UUID=ac0f0548-a69d-43ca-a06b-7db01bcbd5ad ro quiet ...

The second added line shows only those kernel boot parameters supplied
by the boot loader.

Link: https://lore.kernel.org/all/20231005171747.541123-2-paulmck@kernel.org/

Link: https://lore.kernel.org/all/CAHk-=wjpVAW3iRq_bfKnVfs0ZtASh_aT67bQBG11b4W6niYVUw@mail.gmail.com/
Link: https://lore.kernel.org/all/20230731233130.424913-1-paulmck@kernel.org/
Co-developed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: <linux-trace-kernel@vger.kernel.org>
Cc: <linux-fsdevel@vger.kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-10-07 10:45:56 +09:00
Oleg Nesterov
7904e53ed5 fs/proc: do_task_stat: use __for_each_thread()
do/while_each_thread should be avoided when possible.

Link: https://lkml.kernel.org/r/20230909164501.GA11581@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-04 10:41:57 -07:00
Oleg Nesterov
33a9813825 introduce __next_thread(), fix next_tid() vs exec() race
Patch series "introduce __next_thread(), change next_thread()".

After commit dce8f8ed1d ("document while_each_thread(), change
first_tid() to use for_each_thread()") + this series

1. We have only one lockless user of next_thread(), task_group_seq_get_next().
   I think it should be changed too.

2. We have only one user of task_struct->thread_group, thread_group_empty().
   The next patches will change thread_group_empty() and kill ->thread_group.


This patch (of 2):

next_tid(start) does:

	rcu_read_lock();
	if (pid_alive(start)) {
		pos = next_thread(start);
		if (thread_group_leader(pos))
			pos = NULL;
		else
			get_task_struct(pos);

it should return pos = NULL when next_thread() wraps to the 1st thread
in the thread group, group leader, and the thread_group_leader() check
tries to detect this case.

But this can race with exec. To simplify, suppose we have a main thread
M and a single sub-thread T, next_tid(T) should return NULL.

Now suppose that T execs. If next_tid(T) is called after T changes the
leadership and before it does release_task() which removes the old leader
from list, then next_thread() returns M and thread_group_leader(M) = F.

Lockless use of next_thread() should be avoided. After this change only
task_group_seq_get_next() does this, and I believe it should be changed
as well.

Link: https://lkml.kernel.org/r/20230824143112.GA31208@redhat.com
Link: https://lkml.kernel.org/r/20230824143142.GA31222@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-04 10:41:56 -07:00
Qi Zheng
1720f5dd8d fs: super: dynamically allocate the s_shrink
In preparation for implementing lockless slab shrink, use new APIs to
dynamically allocate the s_shrink, so that it can be freed asynchronously
via RCU. Then it doesn't need to wait for RCU read-side critical section
when releasing the struct super_block.

Link: https://lkml.kernel.org/r/20230911094444.68966-39-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: David Sterba <dsterba@suse.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Carlos Llamas <cmllamas@google.com>
Cc: Chandan Babu R <chandan.babu@oracle.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Coly Li <colyli@suse.de>
Cc: Dai Ngo <Dai.Ngo@oracle.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Airlie <airlied@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc: Gao Xiang <hsiangkao@linux.alibaba.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jeffle Xu <jefflexu@linux.alibaba.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Kirill Tkhai <tkhai@ya.ru>
Cc: Marijn Suijten <marijn.suijten@somainline.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nadav Amit <namit@vmware.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Cc: Olga Kornievskaia <kolga@netapp.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Sean Paul <sean@poorly.run>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Song Liu <song@kernel.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Steven Price <steven.price@arm.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Cc: Yue Hu <huyue2@coolpad.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-04 10:32:26 -07:00
Adrian Hunter
e538a58209 proc/kcore: do not try to access unaccepted memory
Support for unaccepted memory was added recently, refer commit
dcdfdd40fa ("mm: Add support for unaccepted memory"), whereby a virtual
machine may need to accept memory before it can be used.

Do not try to access unaccepted memory because it can cause the guest to
fail.

For /proc/kcore, which is read-only and does not support mmap, this means a
read of unaccepted memory will return zeros.

Link: https://lkml.kernel.org/r/20230911112114.91323-3-adrian.hunter@intel.com
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-04 10:32:22 -07:00
Ben Wolsieffer
fe44198016 proc: nommu: fix empty /proc/<pid>/maps
On no-MMU, /proc/<pid>/maps reads as an empty file.  This happens because
find_vma(mm, 0) always returns NULL (assuming no vma actually contains the
zero address, which is normally the case).

To fix this bug and improve the maintainability in the future, this patch
makes the no-MMU implementation as similar as possible to the MMU
implementation.

The only remaining differences are the lack of hold/release_task_mempolicy
and the extra code to shoehorn the gate vma into the iterator.

This has been tested on top of 6.5.3 on an STM32F746.

Link: https://lkml.kernel.org/r/20230915160055.971059-2-ben.wolsieffer@hefring.com
Fixes: 0c563f1480 ("proc: remove VMA rbtree use from nommu")
Signed-off-by: Ben Wolsieffer <ben.wolsieffer@hefring.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Giulio Benetti <giulio.benetti@benettiengineering.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-09-19 13:21:34 -07:00