linux.git/kernel/power/snapshot.c, branch v7.3-rc2 Linux kernel source tree PM: hibernate: Fix memory leak in snapshot_write_next() error path 2026-07-23T13:21:13+00:00 Malaya Kumar Rout malayarout91@gmail.com 2026-07-11T14:52:45+00:00 21d5c4cee31c5ce78f6decc7fafc7e7759af391f When memory_bm_create() succeeds for copy_bm but fails for zero_bm, the function returns without freeing the resources allocated for copy_bm. This results in a memory leak that includes radix tree nodes, zone structures, and page lists. Fix this by calling memory_bm_free() to release copy_bm's resources before returning the error code when zero_bm allocation fails. Fixes: 005e8dddd497 ("PM: hibernate: don't store zero pages in the image file") Signed-off-by: Malaya Kumar Rout <malayarout91@gmail.com> Acked-by: Brian Geffon <bgeffon@google.com> Link: https://patch.msgid.link/20260711145246.8625-1-malayarout91@gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
When memory_bm_create() succeeds for copy_bm but fails for zero_bm,
the function returns without freeing the resources allocated for
copy_bm. This results in a memory leak that includes radix tree nodes,
zone structures, and page lists.

Fix this by calling memory_bm_free() to release copy_bm's resources
before returning the error code when zero_bm allocation fails.

Fixes: 005e8dddd497 ("PM: hibernate: don't store zero pages in the image file")
Signed-off-by: Malaya Kumar Rout <malayarout91@gmail.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Link: https://patch.msgid.link/20260711145246.8625-1-malayarout91@gmail.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM: hibernate: Remove kernel-doc markings from helper descriptions 2026-07-22T12:04:18+00:00 Adi Nata adinata.softwareengineer@gmail.com 2026-06-09T23:16:26+00:00 20919d30f4ec5c3d7356bb4df5a8d2d03709d04d Several helpers in snapshot.c are introduced with kernel-doc (/**) comment blocks but do not describe their parameters with @param tags.This emits warnings when building with extra warnings enabled (make W=1), for example: kernel/power/snapshot.c:469: warning: Function parameter or member 'zone' not described in 'add_rtree_block' kernel/power/snapshot.c:469: warning: Function parameter or member 'gfp_mask' not described in 'add_rtree_block' kernel/power/snapshot.c:469: warning: Function parameter or member 'safe_needed' not described in 'add_rtree_block' kernel/power/snapshot.c:469: warning: Function parameter or member 'ca' not described in 'add_rtree_block' These are file-local implementation details, not part of the exported kernel API documented under Documentation/. Replace the kernel-doc markers with plain block comments for the affected functions. Properly documented symbols such as alloc_rtree_node(), snapshot_read_next() and snapshot_write_next() remain unchanged. Signed-off-by: Adi Nata <adinata.softwareengineer@gmail.com> [ rjw: Subject rewrite ] Link: https://patch.msgid.link/20260609231626.38839-1-adinata.softwareengineer@gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Several helpers in snapshot.c are introduced with kernel-doc (/**)
comment blocks but do not describe their parameters with @param
tags.This emits warnings when building
with extra warnings enabled (make W=1), for example:
kernel/power/snapshot.c:469: warning: Function parameter or member
    'zone' not described in 'add_rtree_block'
kernel/power/snapshot.c:469: warning: Function parameter or member
    'gfp_mask' not described in 'add_rtree_block'
kernel/power/snapshot.c:469: warning: Function parameter or member
    'safe_needed' not described in 'add_rtree_block'
kernel/power/snapshot.c:469: warning: Function parameter or member
    'ca' not described in 'add_rtree_block'

These are file-local implementation details, not part of the
exported kernel API documented under Documentation/. Replace the
kernel-doc markers with plain block comments for the affected
functions.

Properly documented symbols such as
alloc_rtree_node(), snapshot_read_next() and snapshot_write_next()
remain unchanged.

Signed-off-by: Adi Nata <adinata.softwareengineer@gmail.com>
[ rjw: Subject rewrite ]
Link: https://patch.msgid.link/20260609231626.38839-1-adinata.softwareengineer@gmail.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
mm: introduce for_each_free_list() 2026-06-02T22:22:19+00:00 Brendan Jackman jackmanb@google.com 2026-05-13T12:35:13+00:00 9c860d1d5d69f9cb19eb7c36573ee14065a9c85a Patch series "mm: misc cleanups from __GFP_UNMAPPED series". In v2 of the __GFP_UNMAPPED series [0], we realised that some of the patches could potentially be merged as independent cleanups. These are all independent of one another, if you think some are useful cleanups and others are pointless churn, it should be fine to just pick whatever subset you prefer. No functional change intended. This patch (of 4): There are a couple of places that iterate over the freelists with awareness of the data structures' layout. It seems ideally, code outside of mm should not be aware of the page allocator's freelists at all. But, this patch just doesn't hide them completely, it's just a meek incremental step in that direction: provide a macro to iterate over it without needing to be aware of the actual struct fields. Link: https://lore.kernel.org/20260513-page_alloc-unmapped-prep-v1-0-dacdf5402be8@google.com Link: https://lore.kernel.org/20260513-page_alloc-unmapped-prep-v1-1-dacdf5402be8@google.com Link: https://lore.kernel.org/all/20260320-page_alloc-unmapped-v2-0-28bf1bd54f41@google.com/ [0] Signed-off-by: Brendan Jackman <jackmanb@google.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kairui Song <kasong@tencent.com> Cc: Len Brown <lenb@kernel.org> Cc: Liam R. Howlett <liam@infradead.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Wei Xu <weixugc@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> 
Patch series "mm: misc cleanups from __GFP_UNMAPPED series".

In v2 of the __GFP_UNMAPPED series [0], we realised that some of the
patches could potentially be merged as independent cleanups.

These are all independent of one another, if you think some are useful
cleanups and others are pointless churn, it should be fine to just pick
whatever subset you prefer.

No functional change intended.


This patch (of 4):

There are a couple of places that iterate over the freelists with
awareness of the data structures' layout.

It seems ideally, code outside of mm should not be aware of the page
allocator's freelists at all.  But, this patch just doesn't hide them
completely, it's just a meek incremental step in that direction: provide a
macro to iterate over it without needing to be aware of the actual struct
fields.

Link: https://lore.kernel.org/20260513-page_alloc-unmapped-prep-v1-0-dacdf5402be8@google.com
Link: https://lore.kernel.org/20260513-page_alloc-unmapped-prep-v1-1-dacdf5402be8@google.com
Link: https://lore.kernel.org/all/20260320-page_alloc-unmapped-v2-0-28bf1bd54f41@google.com/ [0]
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
PM: hibernate: Drain trailing zero pages on userspace restore 2026-03-23T12:33:06+00:00 Alberto Garcia berto@igalia.com 2026-03-09T17:39:41+00:00 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> 
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>
Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-22T01:09:51+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-02-22T00:37:42+00:00 bf4afc53b77aeaa48b5409da5c8da6bb4eff7f43 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> 
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>
treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21T09:02:28+00:00 Kees Cook kees@kernel.org 2026-02-21T07:49:23+00:00 69050f8d6d075dc01af7a5f2f550a8067510366f 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> 
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>
PM: hibernate: Rework message printing in swsusp_save() 2025-10-20T18:43:09+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2025-10-09T19:34:16+00:00 d3db87f89c71c34f4a6a0ee9de3dfab5eee18b22 The messages printed by swsusp_save() are basically only useful for debug, so printing them every time a hibernation image is created at the "info" log level is not particularly useful. Also printing a message on a failing memory allocation is redundant. Use pm_deferred_pr_dbg() for printing those messages so they will only be printed when requested and the "deferred" variant is used because this code runs in a deeply atomic context (one CPU with interrupts off, no functional devices). Also drop the useless message printed when memory allocations fails. While at it, extend one of the messages in question so it is less cryptic. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [ rjw: Dropped a useless colon at the end of one of the messages ] Link: https://patch.msgid.link/10750389.nUPlyArG6x@rafael.j.wysocki 
The messages printed by swsusp_save() are basically only useful for
debug, so printing them every time a hibernation image is created at
the "info" log level is not particularly useful.  Also printing a
message on a failing memory allocation is redundant.

Use pm_deferred_pr_dbg() for printing those messages so they will only
be printed when requested and the "deferred" variant is used because
this code runs in a deeply atomic context (one CPU with interrupts
off, no functional devices).  Also drop the useless message printed
when memory allocations fails.

While at it, extend one of the messages in question so it is less
cryptic.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[ rjw: Dropped a useless colon at the end of one of the messages ]
Link: https://patch.msgid.link/10750389.nUPlyArG6x@rafael.j.wysocki
PM: hibernate: Fix typo in memory bitmaps description comment 2025-09-01T09:55:53+00:00 Li Jun lijun01@kylinos.cn 2025-08-19T10:40:38+00:00 98da8a4aecf584af011cdc67d9581deb21088f24 Correct 'leave' to 'leaf' in memory bitmaps description comment. Signed-off-by: Li Jun <lijun01@kylinos.cn> Link: https://patch.msgid.link/20250819104038.1596952-1-lijun01@kylinos.cn [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Correct 'leave' to 'leaf' in memory bitmaps description comment.

Signed-off-by: Li Jun <lijun01@kylinos.cn>
Link: https://patch.msgid.link/20250819104038.1596952-1-lijun01@kylinos.cn
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM: hibernate: Fix up white space that does not follow coding style 2025-07-17T18:30:52+00:00 Darshan Rathod darshanrathod475@gmail.com 2025-07-16T12:42:16+00:00 f633c1a236df95ab927f1919b3be2619c8cc6733 Fix up white space usage that does not follow the kernel coding style rules in several places in snapshot.c. Signed-off-by: Darshan Rathod <darshanrathod475@gmail.com> Link: https://patch.msgid.link/20250716124216.64329-1-darshanrathod475@gmail.com [ rjw: New subject and changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 
Fix up white space usage that does not follow the kernel coding style
rules in several places in snapshot.c.

Signed-off-by: Darshan Rathod <darshanrathod475@gmail.com>
Link: https://patch.msgid.link/20250716124216.64329-1-darshanrathod475@gmail.com
[ rjw: New subject and changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
mm, PM: use for_each_valid_pfn() in kernel/power/snapshot.c 2025-05-13T06:50:44+00:00 David Woodhouse dwmw@amazon.co.uk 2025-04-23T13:33:40+00:00 312eca8a14c5f58de62692517afd4738099e6fac Link: https://lkml.kernel.org/r/20250423133821.789413-5-dwmw2@infradead.org Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Ruihan Li <lrh2000@pku.edu.cn> Cc: Will Deacon <will@kernel.org> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> 
Link: https://lkml.kernel.org/r/20250423133821.789413-5-dwmw2@infradead.org
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Ruihan Li <lrh2000@pku.edu.cn>
Cc: Will Deacon <will@kernel.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>