linux.git/kernel/power, branch v6.18.21 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git PM: sleep: Drop spurious WARN_ON() from pm_restore_gfp_mask() 2026-04-02T11:23:13+00:00 Youngjun Park youngjun.park@lge.com 2026-03-22T12:05:28+00:00 3025ca5daa9d682b629c0c958b538e41deeb559d [ Upstream commit a8d51efb5929ae308895455a3e496b5eca2cd143 ] Commit 35e4a69b2003f ("PM: sleep: Allow pm_restrict_gfp_mask() stacking") introduced refcount-based GFP mask management that warns when pm_restore_gfp_mask() is called with saved_gfp_count == 0. Some hibernation paths call pm_restore_gfp_mask() defensively where the GFP mask may or may not be restricted depending on the execution path. For example, the uswsusp interface invokes it in SNAPSHOT_CREATE_IMAGE, SNAPSHOT_UNFREEZE, and snapshot_release(). Before the stacking change this was a silent no-op; it now triggers a spurious WARNING. Remove the WARN_ON() wrapper from the !saved_gfp_count check while retaining the check itself, so that defensive calls remain harmless without producing false warnings. Fixes: 35e4a69b2003f ("PM: sleep: Allow pm_restrict_gfp_mask() stacking") Signed-off-by: Youngjun Park <youngjun.park@lge.com> [ rjw: Subject tweak ] Link: https://patch.msgid.link/20260322120528.750178-1-youngjun.park@lge.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit a8d51efb5929ae308895455a3e496b5eca2cd143 ]

Commit 35e4a69b2003f ("PM: sleep: Allow pm_restrict_gfp_mask()
stacking") introduced refcount-based GFP mask management that warns
when pm_restore_gfp_mask() is called with saved_gfp_count == 0.

Some hibernation paths call pm_restore_gfp_mask() defensively where
the GFP mask may or may not be restricted depending on the execution
path. For example, the uswsusp interface invokes it in
SNAPSHOT_CREATE_IMAGE, SNAPSHOT_UNFREEZE, and snapshot_release().
Before the stacking change this was a silent no-op; it now triggers
a spurious WARNING.

Remove the WARN_ON() wrapper from the !saved_gfp_count check while
retaining the check itself, so that defensive calls remain harmless
without producing false warnings.

Fixes: 35e4a69b2003f ("PM: sleep: Allow pm_restrict_gfp_mask() stacking")
Signed-off-by: Youngjun Park <youngjun.park@lge.com>
[ rjw: Subject tweak ]
Link: https://patch.msgid.link/20260322120528.750178-1-youngjun.park@lge.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
PM: hibernate: Drain trailing zero pages on userspace restore 2026-04-02T11:23:13+00:00 Alberto Garcia berto@igalia.com 2026-03-09T17:39:41+00:00 13a6af01c1e3b0b019922616d59d04144d99d83a [ Upstream commit 734eba62cd32cb9ceffa09e57cdc03d761528525 ] Commit 005e8dddd497 ("PM: hibernate: don't store zero pages in the image file") added an optimization to skip zero-filled pages in the hibernation image. On restore, zero pages are handled internally by snapshot_write_next() in a loop that processes them without returning to the caller. With the userspace restore interface, writing the last non-zero page to /dev/snapshot is followed by the SNAPSHOT_ATOMIC_RESTORE ioctl. At this point there are no more calls to snapshot_write_next() so any trailing zero pages are not processed, snapshot_image_loaded() fails because handle->cur is smaller than expected, the ioctl returns -EPERM and the image is not restored. The in-kernel restore path is not affected by this because the loop in load_image() in swap.c calls snapshot_write_next() until it returns 0. It is this final call that drains any trailing zero pages. Fixed by calling snapshot_write_next() in snapshot_write_finalize(), giving the kernel the chance to drain any trailing zero pages. Fixes: 005e8dddd497 ("PM: hibernate: don't store zero pages in the image file") Signed-off-by: Alberto Garcia <berto@igalia.com> Acked-by: Brian Geffon <bgeffon@google.com> Link: https://patch.msgid.link/ef5a7c5e3e3dbd17dcb20efaa0c53a47a23498bb.1773075892.git.berto@igalia.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 734eba62cd32cb9ceffa09e57cdc03d761528525 ]

Commit 005e8dddd497 ("PM: hibernate: don't store zero pages in the
image file") added an optimization to skip zero-filled pages in the
hibernation image. On restore, zero pages are handled internally by
snapshot_write_next() in a loop that processes them without returning
to the caller.

With the userspace restore interface, writing the last non-zero page
to /dev/snapshot is followed by the SNAPSHOT_ATOMIC_RESTORE ioctl. At
this point there are no more calls to snapshot_write_next() so any
trailing zero pages are not processed, snapshot_image_loaded() fails
because handle->cur is smaller than expected, the ioctl returns -EPERM
and the image is not restored.

The in-kernel restore path is not affected by this because the loop in
load_image() in swap.c calls snapshot_write_next() until it returns 0.
It is this final call that drains any trailing zero pages.

Fixed by calling snapshot_write_next() in snapshot_write_finalize(),
giving the kernel the chance to drain any trailing zero pages.

Fixes: 005e8dddd497 ("PM: hibernate: don't store zero pages in the image file")
Signed-off-by: Alberto Garcia <berto@igalia.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Link: https://patch.msgid.link/ef5a7c5e3e3dbd17dcb20efaa0c53a47a23498bb.1773075892.git.berto@igalia.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
PM: hibernate: Fix crash when freeing invalid crypto compressor 2026-01-17T15:35:14+00:00 Malaya Kumar Rout mrout@redhat.com 2025-12-30T11:56:13+00:00 b7a883b0135dbc6817e90a829421c9fc8cd94bad commit 7966cf0ebe32c981bfa3db252cb5fc3bb1bf2e77 upstream. When crypto_alloc_acomp() fails, it returns an ERR_PTR value, not NULL. The cleanup code in save_compressed_image() and load_compressed_image() unconditionally calls crypto_free_acomp() without checking for ERR_PTR, which causes crypto_acomp_tfm() to dereference an invalid pointer and crash the kernel. This can be triggered when the compression algorithm is unavailable (e.g., CONFIG_CRYPTO_LZO not enabled). Fix by adding IS_ERR_OR_NULL() checks before calling crypto_free_acomp() and acomp_request_free(), similar to the existing kthread_stop() check. Fixes: b03d542c3c95 ("PM: hibernate: Use crypto_acomp interface") Signed-off-by: Malaya Kumar Rout <mrout@redhat.com> Cc: 6.15+ <stable@vger.kernel.org> # 6.15+ [ rjw: Added 2 empty code lines ] Link: https://patch.msgid.link/20251230115613.64080-1-mrout@redhat.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 7966cf0ebe32c981bfa3db252cb5fc3bb1bf2e77 upstream.

When crypto_alloc_acomp() fails, it returns an ERR_PTR value, not NULL.

The cleanup code in save_compressed_image() and load_compressed_image()
unconditionally calls crypto_free_acomp() without checking for ERR_PTR,
which causes crypto_acomp_tfm() to dereference an invalid pointer and
crash the kernel.

This can be triggered when the compression algorithm is unavailable
(e.g., CONFIG_CRYPTO_LZO not enabled).

Fix by adding IS_ERR_OR_NULL() checks before calling crypto_free_acomp()
and acomp_request_free(), similar to the existing kthread_stop() check.

Fixes: b03d542c3c95 ("PM: hibernate: Use crypto_acomp interface")
Signed-off-by: Malaya Kumar Rout <mrout@redhat.com>
Cc: 6.15+ <stable@vger.kernel.org> # 6.15+
[ rjw: Added 2 empty code lines ]
Link: https://patch.msgid.link/20251230115613.64080-1-mrout@redhat.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge tag 'vfs-6.18-rc7.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs 2025-11-17T17:11:27+00:00 Linus Torvalds torvalds@linux-foundation.org 2025-11-17T17:11:27+00:00 e7c375b181600caf135cfd03eadbc45eb530f2cb Pull vfs fixes from Christian Brauner: - Fix unitialized variable in statmount_string() - Fix hostfs mounting when passing host root during boot - Fix dynamic lookup to fail on cell lookup failure - Fix missing file type when reading bfs inodes from disk - Enforce checking of sb_min_blocksize() calls and update all callers accordingly - Restore write access before closing files opened by open_exec() in binfmt_misc - Always freeze efivarfs during suspend/hibernate cycles - Fix statmount()'s and listmount()'s grab_requested_mnt_ns() helper to actually allow mount namespace file descriptor in addition to mount namespace ids - Fix tmpfs remount when noswap is specified - Switch Landlock to iput_not_last() to remove false-positives from might_sleep() annotations in iput() - Remove dead node_to_mnt_ns() code - Ensure that per-queue kobjects are successfully created * tag 'vfs-6.18-rc7.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: landlock: fix splats from iput() after it started calling might_sleep() fs: add iput_not_last() shmem: fix tmpfs reconfiguration (remount) when noswap is set fs/namespace: correctly handle errors returned by grab_requested_mnt_ns power: always freeze efivarfs binfmt_misc: restore write access before closing files opened by open_exec() block: add __must_check attribute to sb_min_blocksize() virtio-fs: fix incorrect check for fsvq->kobj xfs: check the return value of sb_min_blocksize() in xfs_fs_fill_super isofs: check the return value of sb_min_blocksize() in isofs_fill_super exfat: check return value of sb_min_blocksize in exfat_read_boot_sector vfat: fix missing sb_min_blocksize() return value checks mnt: Remove dead code which might prevent from building bfs: Reconstruct file type when loading from disk afs: Fix dynamic lookup to fail on cell lookup failure hostfs: Fix only passing host root in boot stage with new mount fs: Fix uninitialized 'offp' in statmount_string() 
Pull vfs fixes from Christian Brauner:

 - Fix unitialized variable in statmount_string()

 - Fix hostfs mounting when passing host root during boot

 - Fix dynamic lookup to fail on cell lookup failure

 - Fix missing file type when reading bfs inodes from disk

 - Enforce checking of sb_min_blocksize() calls and update all callers
   accordingly

 - Restore write access before closing files opened by open_exec() in
   binfmt_misc

 - Always freeze efivarfs during suspend/hibernate cycles

 - Fix statmount()'s and listmount()'s grab_requested_mnt_ns() helper to
   actually allow mount namespace file descriptor in addition to mount
   namespace ids

 - Fix tmpfs remount when noswap is specified

 - Switch Landlock to iput_not_last() to remove false-positives from
   might_sleep() annotations in iput()

 - Remove dead node_to_mnt_ns() code

 - Ensure that per-queue kobjects are successfully created

* tag 'vfs-6.18-rc7.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs:
  landlock: fix splats from iput() after it started calling might_sleep()
  fs: add iput_not_last()
  shmem: fix tmpfs reconfiguration (remount) when noswap is set
  fs/namespace: correctly handle errors returned by grab_requested_mnt_ns
  power: always freeze efivarfs
  binfmt_misc: restore write access before closing files opened by open_exec()
  block: add __must_check attribute to sb_min_blocksize()
  virtio-fs: fix incorrect check for fsvq->kobj
  xfs: check the return value of sb_min_blocksize() in xfs_fs_fill_super
  isofs: check the return value of sb_min_blocksize() in isofs_fill_super
  exfat: check return value of sb_min_blocksize in exfat_read_boot_sector
  vfat: fix missing sb_min_blocksize() return value checks
  mnt: Remove dead code which might prevent from building
  bfs: Reconstruct file type when loading from disk
  afs: Fix dynamic lookup to fail on cell lookup failure
  hostfs: Fix only passing host root in boot stage with new mount
  fs: Fix uninitialized 'offp' in statmount_string()
power: always freeze efivarfs 2025-11-12T09:12:39+00:00 Christian Brauner brauner@kernel.org 2025-11-05T13:39:45+00:00 a3f8f8662771285511ae26c4c8d3ba1cd22159b9 The efivarfs filesystems must always be frozen and thawed to resync variable state. Make it so. Link: https://patch.msgid.link/20251105-vorbild-zutreffen-fe00d1dd98db@brauner Signed-off-by: Christian Brauner <brauner@kernel.org> 
The efivarfs filesystems must always be frozen and thawed to resync
variable state. Make it so.

Link: https://patch.msgid.link/20251105-vorbild-zutreffen-fe00d1dd98db@brauner
Signed-off-by: Christian Brauner <brauner@kernel.org>
PM: hibernate: Fix style issues in save_compressed_image() 2025-11-07T15:53:57+00:00 Mario Limonciello (AMD) superm1@kernel.org 2025-11-06T04:51:07+00:00 0b6c10cb8479d0d1b7b208277df2e2afe082d4bd Address two issues indicated by checkpatch: - Trailing statements should be on next line. - Prefer 'unsigned int' to bare use of 'unsigned'. Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org> [ rjw: Changelog edits ] Link: https://patch.msgid.link/20251106045158.3198061-4-superm1@kernel.org Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Address two issues indicated by checkpatch:

 - Trailing statements should be on next line.
 - Prefer 'unsigned int' to bare use of 'unsigned'.

Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
[ rjw: Changelog edits ]
Link: https://patch.msgid.link/20251106045158.3198061-4-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM: hibernate: Use atomic64_t for compressed_size variable 2025-11-07T15:53:56+00:00 Mario Limonciello (AMD) superm1@kernel.org 2025-11-06T04:51:06+00:00 66ededc694f1d06a71ca35a3c8e3689e9b85b3ce `compressed_size` can overflow, showing nonsensical values. Change from `atomic_t` to `atomic64_t` to prevent overflow. Fixes: a06c6f5d3cc9 ("PM: hibernate: Move to crypto APIs for LZO compression") Reported-by: Askar Safin <safinaskar@gmail.com> Closes: https://lore.kernel.org/linux-pm/20251105180506.137448-1-safinaskar@gmail.com/ Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org> Tested-by: Askar Safin <safinaskar@gmail.com> Cc: 6.9+ <stable@vger.kernel.org> # 6.9+ Link: https://patch.msgid.link/20251106045158.3198061-3-superm1@kernel.org Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
`compressed_size` can overflow, showing nonsensical values.

Change from `atomic_t` to `atomic64_t` to prevent overflow.

Fixes: a06c6f5d3cc9 ("PM: hibernate: Move to crypto APIs for LZO compression")
Reported-by: Askar Safin <safinaskar@gmail.com>
Closes: https://lore.kernel.org/linux-pm/20251105180506.137448-1-safinaskar@gmail.com/
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Tested-by: Askar Safin <safinaskar@gmail.com>
Cc: 6.9+ <stable@vger.kernel.org> # 6.9+
Link: https://patch.msgid.link/20251106045158.3198061-3-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM: hibernate: Emit an error when image writing fails 2025-11-07T15:53:56+00:00 Mario Limonciello (AMD) superm1@kernel.org 2025-11-06T04:51:05+00:00 62b9ca1706e1bbb60d945a58de7c7b5826f6b2a2 If image writing fails, a return code is passed up to the caller, but none of the callers log anything to the log and so the only record of it is the return code that userspace gets. Adjust the logging so that the image size and speed of writing is only emitted on success and if there is an error, it's saved to the logs. Fixes: a06c6f5d3cc9 ("PM: hibernate: Move to crypto APIs for LZO compression") Reported-by: Askar Safin <safinaskar@gmail.com> Closes: https://lore.kernel.org/linux-pm/20251105180506.137448-1-safinaskar@gmail.com/ Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org> Tested-by: Askar Safin <safinaskar@gmail.com> Cc: 6.9+ <stable@vger.kernel.org> # 6.9+ [ rjw: Added missing braces after "else", changelog edits ] Link: https://patch.msgid.link/20251106045158.3198061-2-superm1@kernel.org Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
If image writing fails, a return code is passed up to the caller, but
none of the callers log anything to the log and so the only record
of it is the return code that userspace gets.

Adjust the logging so that the image size and speed of writing is
only emitted on success and if there is an error, it's saved to the
logs.

Fixes: a06c6f5d3cc9 ("PM: hibernate: Move to crypto APIs for LZO compression")
Reported-by: Askar Safin <safinaskar@gmail.com>
Closes: https://lore.kernel.org/linux-pm/20251105180506.137448-1-safinaskar@gmail.com/
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Tested-by: Askar Safin <safinaskar@gmail.com>
Cc: 6.9+ <stable@vger.kernel.org> # 6.9+
[ rjw: Added missing braces after "else", changelog edits ]
Link: https://patch.msgid.link/20251106045158.3198061-2-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM: sleep: Allow pm_restrict_gfp_mask() stacking 2025-10-29T17:55:32+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2025-10-28T20:52:31+00:00 35e4a69b2003f20a69e7d19ae96ab1eef1aa8e8d Allow pm_restrict_gfp_mask() to be called many times in a row to avoid issues with calling dpm_suspend_start() when the GFP mask has been already restricted. Only the first invocation of pm_restrict_gfp_mask() will actually restrict the GFP mask and the subsequent calls will warn if there is a mismatch between the expected allowed GFP mask and the actual one. Moreover, if pm_restrict_gfp_mask() is called many times in a row, pm_restore_gfp_mask() needs to be called matching number of times in a row to actually restore the GFP mask. Calling it when the GFP mask has not been restricted will cause it to warn. This is necessary for the GFP mask restriction starting in hibernation_snapshot() to continue throughout the entire hibernation flow until it completes or it is aborted (either by a wakeup event or by an error). Fixes: 449c9c02537a1 ("PM: hibernate: Restrict GFP mask in hibernation_snapshot()") Fixes: 469d80a3712c ("PM: hibernate: Fix hybrid-sleep") Reported-by: Askar Safin <safinaskar@gmail.com> Closes: https://lore.kernel.org/linux-pm/20251025050812.421905-1-safinaskar@gmail.com/ Link: https://lore.kernel.org/linux-pm/20251028111730.2261404-1-safinaskar@gmail.com/ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org> Tested-by: Mario Limonciello (AMD) <superm1@kernel.org> Cc: 6.16+ <stable@vger.kernel.org> # 6.16+ Link: https://patch.msgid.link/5935682.DvuYhMxLoT@rafael.j.wysocki 
Allow pm_restrict_gfp_mask() to be called many times in a row to avoid
issues with calling dpm_suspend_start() when the GFP mask has been
already restricted.

Only the first invocation of pm_restrict_gfp_mask() will actually
restrict the GFP mask and the subsequent calls will warn if there is
a mismatch between the expected allowed GFP mask and the actual one.

Moreover, if pm_restrict_gfp_mask() is called many times in a row,
pm_restore_gfp_mask() needs to be called matching number of times in
a row to actually restore the GFP mask.  Calling it when the GFP mask
has not been restricted will cause it to warn.

This is necessary for the GFP mask restriction starting in
hibernation_snapshot() to continue throughout the entire hibernation
flow until it completes or it is aborted (either by a wakeup event or
by an error).

Fixes: 449c9c02537a1 ("PM: hibernate: Restrict GFP mask in hibernation_snapshot()")
Fixes: 469d80a3712c ("PM: hibernate: Fix hybrid-sleep")
Reported-by: Askar Safin <safinaskar@gmail.com>
Closes: https://lore.kernel.org/linux-pm/20251025050812.421905-1-safinaskar@gmail.com/
Link: https://lore.kernel.org/linux-pm/20251028111730.2261404-1-safinaskar@gmail.com/
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Tested-by: Mario Limonciello (AMD) <superm1@kernel.org>
Cc: 6.16+ <stable@vger.kernel.org> # 6.16+
Link: https://patch.msgid.link/5935682.DvuYhMxLoT@rafael.j.wysocki
Revert "PM: sleep: Make pm_wakeup_clear() call more clear" 2025-10-23T10:48:04+00:00 Samuel Wu wusamuel@google.com 2025-10-22T22:28:30+00:00 79816d4b9e9b9bb03d5d871c04c97b1bce102b14 This reverts commit 56a232d93cea0ba14da5e3157830330756a45b4c. The above commit changed the position of pm_wakeup_clear() for the suspend call path, but other call paths with references to freeze_processes() were not updated. This means that other call paths, such as hibernate(), will not have pm_wakeup_clear() called. Suggested-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Samuel Wu <wusamuel@google.com> [ rjw: Changelog edits ] Link: https://patch.msgid.link/20251022222830.634086-1-wusamuel@google.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
This reverts commit 56a232d93cea0ba14da5e3157830330756a45b4c.

The above commit changed the position of pm_wakeup_clear() for the
suspend call path, but other call paths with references to
freeze_processes() were not updated. This means that other call
paths, such as hibernate(), will not have pm_wakeup_clear() called.

Suggested-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Samuel Wu <wusamuel@google.com>
[ rjw: Changelog edits ]
Link: https://patch.msgid.link/20251022222830.634086-1-wusamuel@google.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>