linux.git/kernel/power/swap.c, branch v6.18.22

PM: hibernate: Fix crash when freeing invalid crypto compressor

2026-01-17T15:35:14+00:00

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 
Cc: 6.15+  # 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 
Signed-off-by: Greg Kroah-Hartman

PM: hibernate: Fix style issues in save_compressed_image()

2025-11-07T15:53:57+00:00

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) 
[ rjw: Changelog edits ]
Link: https://patch.msgid.link/20251106045158.3198061-4-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki

PM: hibernate: Use atomic64_t for compressed_size variable

2025-11-07T15:53:56+00:00

`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 
Closes: https://lore.kernel.org/linux-pm/20251105180506.137448-1-safinaskar@gmail.com/
Signed-off-by: Mario Limonciello (AMD) 
Tested-by: Askar Safin 
Cc: 6.9+  # 6.9+
Link: https://patch.msgid.link/20251106045158.3198061-3-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki

PM: hibernate: Emit an error when image writing fails

2025-11-07T15:53:56+00:00

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 
Closes: https://lore.kernel.org/linux-pm/20251105180506.137448-1-safinaskar@gmail.com/
Signed-off-by: Mario Limonciello (AMD) 
Tested-by: Askar Safin 
Cc: 6.9+  # 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

PM: hibernate: Use vmalloc_array() and vcalloc() to improve code

2025-09-01T09:55:53+00:00

Remove array_size() calls and replace vmalloc() and vzalloc() with
vmalloc_array() and vcalloc() respectively to simplify the code in
save_compressed_image() and load_compressed_image().

vmalloc_array() is also optimized better, resulting in less
instructions being used, and vmalloc_array() handling overhead is
lower [1].

Link: https://lore.kernel.org/lkml/abc66ec5-85a4-47e1-9759-2f60ab111971@vivo.com/ [1]
Signed-off-by: Qianfeng Rong 
Link: https://patch.msgid.link/20250817083636.53872-1-rongqianfeng@vivo.com
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki

PM: hibernate: split and simplify hib_submit_io

2025-05-07T13:31:07+00:00

Split hib_submit_io into a sync and async version.  The sync version is
a small wrapper around bdev_rw_virt which implements all the logic to
add a kernel direct mapping range to a bio and synchronously submits it,
while the async version is slightly simplified using the
bio_add_virt_nofail for adding the single range.

Signed-off-by: Christoph Hellwig 
Acked-by: Rafael J. Wysocki 
Reviewed-by: Damien Le Moal 
Link: https://lore.kernel.org/r/20250507120451.4000627-13-hch@lst.de
Signed-off-by: Jens Axboe

PM: hibernate: Use crypto_acomp interface

2025-03-21T09:39:05+00:00

Replace the legacy crypto compression interface with the new acomp
interface.

Signed-off-by: Herbert Xu 
Acked-by: Rafael J. Wysocki 
Signed-off-by: Herbert Xu

mm: remove the implementation of swap_free() and always use swap_free_nr()

2024-07-04T02:30:01+00:00

To streamline maintenance efforts, we propose removing the implementation
of swap_free().  Instead, we can simply invoke swap_free_nr() with nr set
to 1.  swap_free_nr() is designed with a bitmap consisting of only one
long, resulting in overhead that can be ignored for cases where nr equals
1.

A prime candidate for leveraging swap_free_nr() lies within
kernel/power/swap.c.  Implementing this change facilitates the adoption of
batch processing for hibernation.

Link: https://lkml.kernel.org/r/20240529082824.150954-3-21cnbao@gmail.com
Signed-off-by: Barry Song 
Suggested-by: "Huang, Ying" 
Reviewed-by: "Huang, Ying" 
Acked-by: Chris Li 
Reviewed-by: Ryan Roberts 
Cc: "Rafael J. Wysocki" 
Cc: Pavel Machek 
Cc: Len Brown 
Cc: Hugh Dickins 
Cc: Christoph Hellwig 
Cc: Andreas Larsson 
Cc: Baolin Wang 
Cc: Chuanhua Han 
Cc: David Hildenbrand 
Cc: "David S. Miller" 
Cc: Gao Xiang 
Cc: Johannes Weiner 
Cc: Kairui Song 
Cc: Khalid Aziz 
Cc: Matthew Wilcox (Oracle) 
Cc: Suren Baghdasaryan 
Cc: Yosry Ahmed 
Cc: Yu Zhao 
Cc: Zi Yan 
Signed-off-by: Andrew Morton

Merge tag 'vfs-6.10-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2024-05-27T15:09:12+00:00

Pull vfs fixes from Christian Brauner:

 - Fix io_uring based write-through after converting cifs to use the
   netfs library

 - Fix aio error handling when doing write-through via netfs library

 - Fix performance regression in iomap when used with non-large folio
   mappings

 - Fix signalfd error code

 - Remove obsolete comment in signalfd code

 - Fix async request indication in netfs_perform_write() by raising
   BDP_ASYNC when IOCB_NOWAIT is set

 - Yield swap device immediately to prevent spurious EBUSY errors

 - Don't cross a .backup mountpoint from backup volumes in afs to avoid
   infinite loops

 - Fix a race between umount and async request completion in 9p after 9p
   was converted to use the netfs library

* tag 'vfs-6.10-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  netfs, 9p: Fix race between umount and async request completion
  afs: Don't cross .backup mountpoint from backup volume
  swap: yield device immediately
  netfs: Fix setting of BDP_ASYNC from iocb flags
  signalfd: drop an obsolete comment
  signalfd: fix error return code
  iomap: fault in smaller chunks for non-large folio mappings
  filemap: add helper mapping_max_folio_size()
  netfs: Fix AIO error handling when doing write-through
  netfs: Fix io_uring based write-through

swap: yield device immediately

2024-05-24T11:34:08+00:00

Otherwise we can cause spurious EBUSY issues when trying to mount the
rootfs later on.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=218845
Reported-by: Petri Kaukasoina 
Signed-off-by: Christian Brauner