<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/kernel/power, branch master</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>PM: sleep: Allow disabling DPM watchdog by default</title>
<updated>2026-07-23T13:46:34+00:00</updated>
<author>
<name>Tzung-Bi Shih</name>
<email>tzungbi@kernel.org</email>
</author>
<published>2026-07-20T03:08:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dca82e209e5ced94b9e53c004a935bc44162073d'/>
<id>dca82e209e5ced94b9e53c004a935bc44162073d</id>
<content type='text'>
Introduce the "dpm_watchdog_enabled" module parameter to allow the DPM
watchdog to be enabled or disabled at boot time and runtime.

Additionally, introduce the CONFIG_DPM_WATCHDOG_ENABLED Kconfig option
to set the default value of the module parameter at compile time.

The primary motivation for this configurability resolves around Android
GKI (Generic Kernel Image).  We want to enable CONFIG_DPM_WATCHDOG in
the GKI so the feature is available.  However, because the GKI is shared
across many different devices, we don't want to inadvertently affect
devices that are unaware of this feature.  This provides a way to
compile it in, but keep it disabled by default for those devices via the
kernel command line or module parameters.

To maintain backward compatibility, CONFIG_DPM_WATCHDOG_ENABLED relies
on `default y`.  Previously, the DPM watchdog was always active if
CONFIG_DPM_WATCHDOG was set.  Defaulting this new option to 'y' ensures
that the behavior remains unchanged for existing users and defconfigs
when they upgrade.

Signed-off-by: Tzung-Bi Shih &lt;tzungbi@kernel.org&gt;
Link: https://patch.msgid.link/20260720030821.2780257-3-tzungbi@kernel.org
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Introduce the "dpm_watchdog_enabled" module parameter to allow the DPM
watchdog to be enabled or disabled at boot time and runtime.

Additionally, introduce the CONFIG_DPM_WATCHDOG_ENABLED Kconfig option
to set the default value of the module parameter at compile time.

The primary motivation for this configurability resolves around Android
GKI (Generic Kernel Image).  We want to enable CONFIG_DPM_WATCHDOG in
the GKI so the feature is available.  However, because the GKI is shared
across many different devices, we don't want to inadvertently affect
devices that are unaware of this feature.  This provides a way to
compile it in, but keep it disabled by default for those devices via the
kernel command line or module parameters.

To maintain backward compatibility, CONFIG_DPM_WATCHDOG_ENABLED relies
on `default y`.  Previously, the DPM watchdog was always active if
CONFIG_DPM_WATCHDOG was set.  Defaulting this new option to 'y' ensures
that the behavior remains unchanged for existing users and defconfigs
when they upgrade.

Signed-off-by: Tzung-Bi Shih &lt;tzungbi@kernel.org&gt;
Link: https://patch.msgid.link/20260720030821.2780257-3-tzungbi@kernel.org
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: hibernate: swap: defer linking the next map page</title>
<updated>2026-07-23T13:25:00+00:00</updated>
<author>
<name>Haesung Kim</name>
<email>mattkim513@gmail.com</email>
</author>
<published>2026-07-14T07:26:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=032270c30836ef1bf7739b7b9568bd77de1d9a9b'/>
<id>032270c30836ef1bf7739b7b9568bd77de1d9a9b</id>
<content type='text'>
Delay allocating and linking the next swap_map_page until another image
page actually needs to be recorded.

The previous code linked and wrote a new swap map page as soon as the
current one became full. When the image size was an exact multiple of
MAP_PAGE_ENTRIES, that left an empty final map page that existed only to
terminate the on-disk chain.

Instead, keep a full map page in memory and only allocate the next map page
when the next image page arrives. This preserves the resume chain while
avoiding an unnecessary swap slot allocation and write for the empty
swap map page.

Signed-off-by: Haesung Kim &lt;mattkim513@gmail.com&gt;
Link: https://patch.msgid.link/20260714072627.3165744-1-mattkim513@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Delay allocating and linking the next swap_map_page until another image
page actually needs to be recorded.

The previous code linked and wrote a new swap map page as soon as the
current one became full. When the image size was an exact multiple of
MAP_PAGE_ENTRIES, that left an empty final map page that existed only to
terminate the on-disk chain.

Instead, keep a full map page in memory and only allocate the next map page
when the next image page arrives. This preserves the resume chain while
avoiding an unnecessary swap slot allocation and write for the empty
swap map page.

Signed-off-by: Haesung Kim &lt;mattkim513@gmail.com&gt;
Link: https://patch.msgid.link/20260714072627.3165744-1-mattkim513@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: hibernate: Fix memory leak in snapshot_write_next() error path</title>
<updated>2026-07-23T13:21:13+00:00</updated>
<author>
<name>Malaya Kumar Rout</name>
<email>malayarout91@gmail.com</email>
</author>
<published>2026-07-11T14:52:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=21d5c4cee31c5ce78f6decc7fafc7e7759af391f'/>
<id>21d5c4cee31c5ce78f6decc7fafc7e7759af391f</id>
<content type='text'>
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 &lt;malayarout91@gmail.com&gt;
Acked-by: Brian Geffon &lt;bgeffon@google.com&gt;
Link: https://patch.msgid.link/20260711145246.8625-1-malayarout91@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;malayarout91@gmail.com&gt;
Acked-by: Brian Geffon &lt;bgeffon@google.com&gt;
Link: https://patch.msgid.link/20260711145246.8625-1-malayarout91@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: hibernate: Use %pe to print error pointer values</title>
<updated>2026-07-22T15:10:53+00:00</updated>
<author>
<name>Ronan Marchal</name>
<email>ronanmarchal29@gmail.com</email>
</author>
<published>2026-06-15T19:18:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=45a7c1077ba759ee59d0549a66ed86e35815e18e'/>
<id>45a7c1077ba759ee59d0549a66ed86e35815e18e</id>
<content type='text'>
Use %pe format specifier instead of %ld with PTR_ERR() to print
error pointers as a symbolic error name (e.g. -ENOMEM) instead
of a raw integer value.

Signed-off-by: Ronan Marchal &lt;ronanmarchal29@gmail.com&gt;
[ rjw: Subject rewrite ]
Link: https://patch.msgid.link/20260615191832.75923-1-ronanmarchal29@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use %pe format specifier instead of %ld with PTR_ERR() to print
error pointers as a symbolic error name (e.g. -ENOMEM) instead
of a raw integer value.

Signed-off-by: Ronan Marchal &lt;ronanmarchal29@gmail.com&gt;
[ rjw: Subject rewrite ]
Link: https://patch.msgid.link/20260615191832.75923-1-ronanmarchal29@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: hibernate: Remove kernel-doc markings from helper descriptions</title>
<updated>2026-07-22T12:04:18+00:00</updated>
<author>
<name>Adi Nata</name>
<email>adinata.softwareengineer@gmail.com</email>
</author>
<published>2026-06-09T23:16:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=20919d30f4ec5c3d7356bb4df5a8d2d03709d04d'/>
<id>20919d30f4ec5c3d7356bb4df5a8d2d03709d04d</id>
<content type='text'>
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 &lt;adinata.softwareengineer@gmail.com&gt;
[ rjw: Subject rewrite ]
Link: https://patch.msgid.link/20260609231626.38839-1-adinata.softwareengineer@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;adinata.softwareengineer@gmail.com&gt;
[ rjw: Subject rewrite ]
Link: https://patch.msgid.link/20260609231626.38839-1-adinata.softwareengineer@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: sleep: Fix off-by-one in wakelocks number limit check</title>
<updated>2026-07-06T18:58:23+00:00</updated>
<author>
<name>Haowen Tu</name>
<email>tuhaowen@uniontech.com</email>
</author>
<published>2026-06-24T05:38:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6058646587dded0ce0ba91bd5a6afbf14fe42055'/>
<id>6058646587dded0ce0ba91bd5a6afbf14fe42055</id>
<content type='text'>
CONFIG_PM_WAKELOCKS_LIMIT is documented as the maximum number of
user-space wakeup sources, but the limit check is performed before
the counter is incremented and only rejects new wakeup sources when the
current number is greater than the limit. This allows one extra wakeup
source to be created.

Reject new wakeup sources once the counter has reached the limit.

Fixes: b86ff9820fd5 ("PM / Sleep: Add user space interface for manipulating wakeup sources, v3")
Signed-off-by: Haowen Tu &lt;tuhaowen@uniontech.com&gt;
[ rjw: Subject edits ]
Link: https://patch.msgid.link/20260624053839.2150567-1-tuhaowen@uniontech.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
CONFIG_PM_WAKELOCKS_LIMIT is documented as the maximum number of
user-space wakeup sources, but the limit check is performed before
the counter is incremented and only rejects new wakeup sources when the
current number is greater than the limit. This allows one extra wakeup
source to be created.

Reject new wakeup sources once the counter has reached the limit.

Fixes: b86ff9820fd5 ("PM / Sleep: Add user space interface for manipulating wakeup sources, v3")
Signed-off-by: Haowen Tu &lt;tuhaowen@uniontech.com&gt;
[ rjw: Subject edits ]
Link: https://patch.msgid.link/20260624053839.2150567-1-tuhaowen@uniontech.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2026-06-18-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2026-06-19T17:14:34+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-06-19T17:14:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a552c81ff4a16738ca5a44a177d552eb38d552ce'/>
<id>a552c81ff4a16738ca5a44a177d552eb38d552ce</id>
<content type='text'>
Pull MM updates from Andrew Morton:

 - "selftests/mm: clean up build output and verbosity" (Li Wang)

   Remove some noise from the MM selftests build

 - "mm: Free contiguous order-0 pages efficiently" (Ryan Roberts)

   Speed up the freeing of a batch of 0-order pages by first scanning
   them for coalescing opportunities. This is applicable to vfree() and
   to the releasing of frozen pages

 - "mm/damon: introduce DAMOS failed region quota charge ratio"
   (SeongJae Park)

   Address a DAMOS usability issue: The DAMOS quota often exhausts
   prematurely because it charges for all memory attempted, causing slow
   and inconsistent performance when actions fail on unreclaimable
   memory.

   To fix this, a new feature lets users set a smaller, flexible quota
   charge ratio (via a numerator and denominator) for failed regions.
   Since failed actions cause less overhead, reducing their quota cost
   ensures more predictable and efficient DAMOS processing

 - "selftests/cgroup: improve zswap tests robustness and support large
   page sizes" (Li Wang)

   Fix various spurious failures and improves the overall robustness of
   the cgroup zswap selftests

 - "fix MAP_DROPPABLE not supported errno" (Anthony Yznaga)

   Fix an issue in the mlock selftests on arm32

 - "mm: huge_memory: clean up defrag sysfs with shared" (Breno Leitao)

   Some maintenance work in the huge_memory code

 - "treewide: fixup gfp_t printks" (Brendan Jackman)

   Use the special vprintf() gfp_t conversion in various places

 - "mm: Fix vmemmap optimization accounting and initialization" (Muchun
   Song)

   Fix several bugs in the vmemmap optimization, mainly around incorrect
   page accounting and memmap initialization in the DAX and memory
   hotplug paths. It also fixes pageblock migratetype initialization and
   struct page initialization for ZONE_DEVICE compound pages

 - "mm/damon: repost non-hotfix reviewed patches in damon/next tree"

   A sprinkle of unrelated minor bugfixes for DAMON

 - "mm: remove page_mapped()" (David Hildenbrand)

   Remove this function from the tree, replacing it with folio_mapped()

 - "mm/damon: let DAMON be paused and resumed" (SeongJae Park)

   Allow DAMON to be paused and resumed without losing its current state

 - "kasan: hw_tags: Disable tagging for stack and page-tables" (Muhammad
   Usama Anjum)

   Simplify and speed up kasan by removing its ineffective tagging of
   stacks and page tables

 - "mm/damon/reclaim,lru_sort: monitor all system rams by default"
   (SeongJae Park)

   Simplify deployment on diverse hardware like NUMA systems by updating
   DAMON_RECLAIM and DAMON_LRU_SORT to automatically monitor the
   physical address range covering all System RAM areas by default,
   replacing the overly restrictive behavior that only targeted the
   single largest memory block to save on negligible overhead

 - "mm/damon/sysfs: document filters/ directory as deprecated" (SeongJae
   Park)

   Update some DAMON docs

 - "mm: use spinlock guards for zone lock" (Dmitry Ilvokhin)

   Switch zone-&gt;lock handling over to using the guard() mechanisms

 - "mm/filemap: tighten mmap_miss hit accounting" (fujunjie)

   Fix a flaw where the mmap_miss counter over-credited page cache hits
   during fault-arounds and page-fault retries. This results in
   significant reduction of redundant synchronous mmap readahead I/O,
   drastically cutting down execution time and gigabytes read for sparse
   random or strided memory access workloads

 - "selftests/cgroup: Fix false positive failures in test_percpu_basic"
   (Li Wang)

   Fix a couple of false-positives in the cgroup kmem selftests

 - "mm/damon/reclaim: support monitoring intervals auto-tuning"
   (SeongJae Park)

   Add a new parameter to DAMON permitting DAMON_RECLAIM to
   automatically tune DAMON's sampling and aggregation intervals

 - "mm/damon/stat: add kdamond_pid parameter" (SeongJae Park)

   Change DAMON_STAT to provide the pid of its kdamond

 - "mm/kmemleak: dedupe verbose scan output" (Breno Leitao)

   Remove large amounts of duplicated backtraces from the verbose-mode
   kmemleak output

 - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 1)" (David
   Hildenbrand)

   Reduce our use of CONFIG_HAVE_BOOTMEM_INFO_NODE, with a view to
   removing it entirely in a later series

 - "mm/damon: validate min_region_size to be power of 2" (Liew Rui Yan)

   Prevent users from passing a non-power-of-2 value of `addr_unit', as
   this later results in undesirable behavior

 - "mm: document read_pages and simplify usage" (Frederick Mayle)

 - "tools/mm/page-types: Fix misc bugs" (Ye Liu)

   Fix three issues in tools/mm/page-types.c

 - "mm: misc cleanups from __GFP_UNMAPPED series" (Brendan Jackman)

   Implement several cleanups in the page allocator and related code

 - "mm, swap: swap table phase IV: unify allocation" (Kairui Song)

   Unify the allocation and charging of anon and shmem swap in folios,
   provides better synchronization, consolidates the metadata
   management, hence dropping the static array and map, and improves
   performance

 - "mm/damon: introduce data attributes monitoring" (SeongJae Park(

   Extend DAMON to monitor general data attributes other than accesses

 - "mm/vmalloc: free unused pages on vrealloc() shrink" (Shivam Kalra)

   Implement the TODO in vrealloc() to unmap and free unused pages when
   shrinking across a page boundary

 - "mm/damon: documentation and comment fixes" (niecheng)

 - "remove mmap_action success, error hooks" (Lorenzo Stoakes)

   Eliminate custom hooks from mmap_action by removing the problematic
   success_hook which allowed drivers to improperly access uninitialized
   VMAs. It replaces the error_hook with a simple error-code field and
   updates the memory char driver accordingly

 - "mm/damon: minor improvements for code readability and tests"
   (SeongJae Park)

 - "mm/damon: fix macro arguments and clarify quota goals doc" (Maksym
   Shcherba)

 - "userfaultfd: merge fs/userfaultfd.c into mm/userfaultfd.c" (Mike
   Rapoport)

 - "mm/mglru: improve reclaim loop and dirty folio" (Kairui Song and
   others)

   Clean up and slightly improves MGLRU's reclaim loop and dirty
   writeback handling. Large performance improvements are measured

 - "use vma locks for proc/pid/{smaps|numa_maps} reads" (Suren
   Baghdasaryan)

   Use per-vma locks when reading /proc/pid/smaps and numa_maps similar
   to reduce contention on central mmap_lock

 - "refactors thpsize_shmem_enabled_store() and thpsize_shmem_enabled_show()"
   (Ran Xiaokai)

   Some cleanup work in the THP code

 - "selftests/memfd: fix compilation warnings" (Konstantin Khorenko)

   Fix a few build glitches in the memfd selftest code.

 - "memcg: shrink obj_stock_pcp and cache multiple objcgs" (Shakeel
   Butt)

   Resolve a 68% performance regression caused by NUMA-node cache
   thrashing around struct obj_stock_pcp by shrinking its existing
   fields and expanding it into a multi-slot array that caches up to
   five obj_cgroup pointers per CPU, allowing per-node variants of the
   same memcg to coexist within a single 64-byte cache line.

 - "zram: writeback fixes" (Sergey Senozhatsky)

   address a couple of unrelated zram writeback issues

 - "mm: switch THP shrinker to list_lru" (Johannes Weiner)

   Resolve NUMA-awareness issues and streamlines callsite interaction by
   refactoring and extending the list_lru API to completely replace the
   complex, open-coded deferred split queue for Transparent Huge Pages

 - "mm: improve large folio readahead for exec memory" (Usama Arif)

   Improve large-folio readahead on systems like 64K-page arm64 by
   preventing the mmap_miss check from permanently disabling
   target-oriented VM_EXEC readahead, and by generalizing the
   force_thp_readahead gate to support mappings with any usefully large
   maximum folio order under the cache cap.

 - "userfaultfd/pagemap: pre-existing fixes" (Kiryl Shutsemau)

   Fix a bunch of minor issues in the userfaultfd/pagemap, all of which
   were flagged by Sashiko review of proposed new material

 - "mm/sparse-vmemmap: Provide generic vmemmap_set_pmd() and
   vmemmap_check_pmd()" (Muchun Song)

   Provide generic versions of these two functions so the four
   arch-specific implementations can be removed.

 - "mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap
   device" (Youngjun Park)

   Address a uswsusp-vs-swapoff race and reduces the swap device
   reference taking/releasing frequency.

 - "mm/hmm: A fix and a selftest" (Dev Jain)

* tag 'mm-stable-2026-06-18-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
  selftests/mm/hmm-tests: test pagemap reads of PMD device-private entries
  fs/proc/task_mmu: do not warn on seeing non-migration pmd entry
  lib/test_hmm: check alloc_page_vma() return value and handle OOM
  mm/compaction: cap compact_gap() at COMPACT_CLUSTER_MAX
  mm/swap: remove redundant swap device reference in alloc/free
  mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device
  mm/filemap: use folio_next_index() for start
  vmalloc: fix NULL pointer dereference in is_vm_area_hugepages()
  sparc/mm: drop vmemmap_check_pmd helper and use generic code
  loongarch/mm: drop vmemmap_check_pmd helper and use generic code
  riscv/mm: drop vmemmap_pmd helpers and use generic code
  arm64/mm: drop vmemmap_pmd helpers and use generic code
  mm/sparse-vmemmap: provide generic vmemmap_set_pmd() and vmemmap_check_pmd()
  rust: page: mark Page::nid as inline
  userfaultfd: build __VMA_UFFD_FLAGS from config-gated masks
  userfaultfd: gate must_wait writability check on pte_present()
  mm/huge_memory: preserve pmd_swp_uffd_wp on device-private PMD downgrade
  fs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole()
  fs/proc/task_mmu: use huge_page_size() in pagemap_scan_hugetlb_entry()
  fs/proc/task_mmu: fix make_uffd_wp_huge_pte() prot-update race
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull MM updates from Andrew Morton:

 - "selftests/mm: clean up build output and verbosity" (Li Wang)

   Remove some noise from the MM selftests build

 - "mm: Free contiguous order-0 pages efficiently" (Ryan Roberts)

   Speed up the freeing of a batch of 0-order pages by first scanning
   them for coalescing opportunities. This is applicable to vfree() and
   to the releasing of frozen pages

 - "mm/damon: introduce DAMOS failed region quota charge ratio"
   (SeongJae Park)

   Address a DAMOS usability issue: The DAMOS quota often exhausts
   prematurely because it charges for all memory attempted, causing slow
   and inconsistent performance when actions fail on unreclaimable
   memory.

   To fix this, a new feature lets users set a smaller, flexible quota
   charge ratio (via a numerator and denominator) for failed regions.
   Since failed actions cause less overhead, reducing their quota cost
   ensures more predictable and efficient DAMOS processing

 - "selftests/cgroup: improve zswap tests robustness and support large
   page sizes" (Li Wang)

   Fix various spurious failures and improves the overall robustness of
   the cgroup zswap selftests

 - "fix MAP_DROPPABLE not supported errno" (Anthony Yznaga)

   Fix an issue in the mlock selftests on arm32

 - "mm: huge_memory: clean up defrag sysfs with shared" (Breno Leitao)

   Some maintenance work in the huge_memory code

 - "treewide: fixup gfp_t printks" (Brendan Jackman)

   Use the special vprintf() gfp_t conversion in various places

 - "mm: Fix vmemmap optimization accounting and initialization" (Muchun
   Song)

   Fix several bugs in the vmemmap optimization, mainly around incorrect
   page accounting and memmap initialization in the DAX and memory
   hotplug paths. It also fixes pageblock migratetype initialization and
   struct page initialization for ZONE_DEVICE compound pages

 - "mm/damon: repost non-hotfix reviewed patches in damon/next tree"

   A sprinkle of unrelated minor bugfixes for DAMON

 - "mm: remove page_mapped()" (David Hildenbrand)

   Remove this function from the tree, replacing it with folio_mapped()

 - "mm/damon: let DAMON be paused and resumed" (SeongJae Park)

   Allow DAMON to be paused and resumed without losing its current state

 - "kasan: hw_tags: Disable tagging for stack and page-tables" (Muhammad
   Usama Anjum)

   Simplify and speed up kasan by removing its ineffective tagging of
   stacks and page tables

 - "mm/damon/reclaim,lru_sort: monitor all system rams by default"
   (SeongJae Park)

   Simplify deployment on diverse hardware like NUMA systems by updating
   DAMON_RECLAIM and DAMON_LRU_SORT to automatically monitor the
   physical address range covering all System RAM areas by default,
   replacing the overly restrictive behavior that only targeted the
   single largest memory block to save on negligible overhead

 - "mm/damon/sysfs: document filters/ directory as deprecated" (SeongJae
   Park)

   Update some DAMON docs

 - "mm: use spinlock guards for zone lock" (Dmitry Ilvokhin)

   Switch zone-&gt;lock handling over to using the guard() mechanisms

 - "mm/filemap: tighten mmap_miss hit accounting" (fujunjie)

   Fix a flaw where the mmap_miss counter over-credited page cache hits
   during fault-arounds and page-fault retries. This results in
   significant reduction of redundant synchronous mmap readahead I/O,
   drastically cutting down execution time and gigabytes read for sparse
   random or strided memory access workloads

 - "selftests/cgroup: Fix false positive failures in test_percpu_basic"
   (Li Wang)

   Fix a couple of false-positives in the cgroup kmem selftests

 - "mm/damon/reclaim: support monitoring intervals auto-tuning"
   (SeongJae Park)

   Add a new parameter to DAMON permitting DAMON_RECLAIM to
   automatically tune DAMON's sampling and aggregation intervals

 - "mm/damon/stat: add kdamond_pid parameter" (SeongJae Park)

   Change DAMON_STAT to provide the pid of its kdamond

 - "mm/kmemleak: dedupe verbose scan output" (Breno Leitao)

   Remove large amounts of duplicated backtraces from the verbose-mode
   kmemleak output

 - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 1)" (David
   Hildenbrand)

   Reduce our use of CONFIG_HAVE_BOOTMEM_INFO_NODE, with a view to
   removing it entirely in a later series

 - "mm/damon: validate min_region_size to be power of 2" (Liew Rui Yan)

   Prevent users from passing a non-power-of-2 value of `addr_unit', as
   this later results in undesirable behavior

 - "mm: document read_pages and simplify usage" (Frederick Mayle)

 - "tools/mm/page-types: Fix misc bugs" (Ye Liu)

   Fix three issues in tools/mm/page-types.c

 - "mm: misc cleanups from __GFP_UNMAPPED series" (Brendan Jackman)

   Implement several cleanups in the page allocator and related code

 - "mm, swap: swap table phase IV: unify allocation" (Kairui Song)

   Unify the allocation and charging of anon and shmem swap in folios,
   provides better synchronization, consolidates the metadata
   management, hence dropping the static array and map, and improves
   performance

 - "mm/damon: introduce data attributes monitoring" (SeongJae Park(

   Extend DAMON to monitor general data attributes other than accesses

 - "mm/vmalloc: free unused pages on vrealloc() shrink" (Shivam Kalra)

   Implement the TODO in vrealloc() to unmap and free unused pages when
   shrinking across a page boundary

 - "mm/damon: documentation and comment fixes" (niecheng)

 - "remove mmap_action success, error hooks" (Lorenzo Stoakes)

   Eliminate custom hooks from mmap_action by removing the problematic
   success_hook which allowed drivers to improperly access uninitialized
   VMAs. It replaces the error_hook with a simple error-code field and
   updates the memory char driver accordingly

 - "mm/damon: minor improvements for code readability and tests"
   (SeongJae Park)

 - "mm/damon: fix macro arguments and clarify quota goals doc" (Maksym
   Shcherba)

 - "userfaultfd: merge fs/userfaultfd.c into mm/userfaultfd.c" (Mike
   Rapoport)

 - "mm/mglru: improve reclaim loop and dirty folio" (Kairui Song and
   others)

   Clean up and slightly improves MGLRU's reclaim loop and dirty
   writeback handling. Large performance improvements are measured

 - "use vma locks for proc/pid/{smaps|numa_maps} reads" (Suren
   Baghdasaryan)

   Use per-vma locks when reading /proc/pid/smaps and numa_maps similar
   to reduce contention on central mmap_lock

 - "refactors thpsize_shmem_enabled_store() and thpsize_shmem_enabled_show()"
   (Ran Xiaokai)

   Some cleanup work in the THP code

 - "selftests/memfd: fix compilation warnings" (Konstantin Khorenko)

   Fix a few build glitches in the memfd selftest code.

 - "memcg: shrink obj_stock_pcp and cache multiple objcgs" (Shakeel
   Butt)

   Resolve a 68% performance regression caused by NUMA-node cache
   thrashing around struct obj_stock_pcp by shrinking its existing
   fields and expanding it into a multi-slot array that caches up to
   five obj_cgroup pointers per CPU, allowing per-node variants of the
   same memcg to coexist within a single 64-byte cache line.

 - "zram: writeback fixes" (Sergey Senozhatsky)

   address a couple of unrelated zram writeback issues

 - "mm: switch THP shrinker to list_lru" (Johannes Weiner)

   Resolve NUMA-awareness issues and streamlines callsite interaction by
   refactoring and extending the list_lru API to completely replace the
   complex, open-coded deferred split queue for Transparent Huge Pages

 - "mm: improve large folio readahead for exec memory" (Usama Arif)

   Improve large-folio readahead on systems like 64K-page arm64 by
   preventing the mmap_miss check from permanently disabling
   target-oriented VM_EXEC readahead, and by generalizing the
   force_thp_readahead gate to support mappings with any usefully large
   maximum folio order under the cache cap.

 - "userfaultfd/pagemap: pre-existing fixes" (Kiryl Shutsemau)

   Fix a bunch of minor issues in the userfaultfd/pagemap, all of which
   were flagged by Sashiko review of proposed new material

 - "mm/sparse-vmemmap: Provide generic vmemmap_set_pmd() and
   vmemmap_check_pmd()" (Muchun Song)

   Provide generic versions of these two functions so the four
   arch-specific implementations can be removed.

 - "mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap
   device" (Youngjun Park)

   Address a uswsusp-vs-swapoff race and reduces the swap device
   reference taking/releasing frequency.

 - "mm/hmm: A fix and a selftest" (Dev Jain)

* tag 'mm-stable-2026-06-18-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
  selftests/mm/hmm-tests: test pagemap reads of PMD device-private entries
  fs/proc/task_mmu: do not warn on seeing non-migration pmd entry
  lib/test_hmm: check alloc_page_vma() return value and handle OOM
  mm/compaction: cap compact_gap() at COMPACT_CLUSTER_MAX
  mm/swap: remove redundant swap device reference in alloc/free
  mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device
  mm/filemap: use folio_next_index() for start
  vmalloc: fix NULL pointer dereference in is_vm_area_hugepages()
  sparc/mm: drop vmemmap_check_pmd helper and use generic code
  loongarch/mm: drop vmemmap_check_pmd helper and use generic code
  riscv/mm: drop vmemmap_pmd helpers and use generic code
  arm64/mm: drop vmemmap_pmd helpers and use generic code
  mm/sparse-vmemmap: provide generic vmemmap_set_pmd() and vmemmap_check_pmd()
  rust: page: mark Page::nid as inline
  userfaultfd: build __VMA_UFFD_FLAGS from config-gated masks
  userfaultfd: gate must_wait writability check on pte_present()
  mm/huge_memory: preserve pmd_swp_uffd_wp on device-private PMD downgrade
  fs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole()
  fs/proc/task_mmu: use huge_page_size() in pagemap_scan_hugetlb_entry()
  fs/proc/task_mmu: fix make_uffd_wp_huge_pte() prot-update race
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branches 'pm-sleep', 'pm-powercap' and 'pm-tools'</title>
<updated>2026-06-11T19:42:36+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2026-06-11T19:42:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5ca48f6f2afc0a0c3f0584f95843451042ffc5ca'/>
<id>5ca48f6f2afc0a0c3f0584f95843451042ffc5ca</id>
<content type='text'>
Merge updates related to system sleep support, two updates of the
intel_rapl power capping driver, and a pm-graph utility fix for
7.2-rc1:

 - Add sysctl interface for DPM watchdog timeouts (Tzung-Bi Shih)

 - Use complete() instead of complete_all() in device_pm_sleep_init() to
   avoid a false-positive warning from lockdep_assert_RT_in_threaded_ctx()
   when CONFIG_PROVE_RAW_LOCK_NESTING is enabled (Jiakai Xu)

 - Use a flexible array for CRC uncompressed buffers during hibernation
   image saving (Rosen Penev)

 - Make the LZ4 algorithm available for hibernation compression (l1rox3)

 - Move the preallocate_image() call during hibernation after the
   "prepare" phase of the "freeze" transition (Matthew Leach)

 - Fix a memory leak in rapl_add_package_cpuslocked() in the intel_rapl
   power capping driver and use sysfs_emit() in cpumask_show() in that
   driver (Sumeet Pawnikar, Yury Norov)

 - Fix ValueError when parsing incomplete device properties in the
   pm-graph utility (Gongwei Li)

* pm-sleep:
  PM: dpm_watchdog: Add sysctl interface for DPM watchdog timeouts
  PM: hibernate: Use flexible array for CRC uncompressed buffers
  PM: hibernate: make LZ4 available for hibernation compression
  PM: sleep: Use complete() in device_pm_sleep_init()
  PM: hibernate: call preallocate_image() after freeze prepare

* pm-powercap:
  powercap: intel_rapl: Use sysfs_emit() in cpumask_show()
  powercap: intel_rapl: Fix memory leak in rapl_add_package_cpuslocked()

* pm-tools:
  PM: tools: pm-graph: fix ValueError when parsing incomplete device properties
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge updates related to system sleep support, two updates of the
intel_rapl power capping driver, and a pm-graph utility fix for
7.2-rc1:

 - Add sysctl interface for DPM watchdog timeouts (Tzung-Bi Shih)

 - Use complete() instead of complete_all() in device_pm_sleep_init() to
   avoid a false-positive warning from lockdep_assert_RT_in_threaded_ctx()
   when CONFIG_PROVE_RAW_LOCK_NESTING is enabled (Jiakai Xu)

 - Use a flexible array for CRC uncompressed buffers during hibernation
   image saving (Rosen Penev)

 - Make the LZ4 algorithm available for hibernation compression (l1rox3)

 - Move the preallocate_image() call during hibernation after the
   "prepare" phase of the "freeze" transition (Matthew Leach)

 - Fix a memory leak in rapl_add_package_cpuslocked() in the intel_rapl
   power capping driver and use sysfs_emit() in cpumask_show() in that
   driver (Sumeet Pawnikar, Yury Norov)

 - Fix ValueError when parsing incomplete device properties in the
   pm-graph utility (Gongwei Li)

* pm-sleep:
  PM: dpm_watchdog: Add sysctl interface for DPM watchdog timeouts
  PM: hibernate: Use flexible array for CRC uncompressed buffers
  PM: hibernate: make LZ4 available for hibernation compression
  PM: sleep: Use complete() in device_pm_sleep_init()
  PM: hibernate: call preallocate_image() after freeze prepare

* pm-powercap:
  powercap: intel_rapl: Use sysfs_emit() in cpumask_show()
  powercap: intel_rapl: Fix memory leak in rapl_add_package_cpuslocked()

* pm-tools:
  PM: tools: pm-graph: fix ValueError when parsing incomplete device properties
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: QoS: Fix misc device registration unwind</title>
<updated>2026-06-09T16:10:46+00:00</updated>
<author>
<name>Yuho Choi</name>
<email>dbgh9129@gmail.com</email>
</author>
<published>2026-06-08T17:07:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=51a7c560cffdd3653ac2b930d01410569b23b23e'/>
<id>51a7c560cffdd3653ac2b930d01410569b23b23e</id>
<content type='text'>
cpu_latency_qos_init() registers cpu_dma_latency first and, when
CONFIG_PM_QOS_CPU_SYSTEM_WAKEUP is enabled, registers cpu_wakeup_latency
afterwards. The second registration overwrites the first return value.

As a result, a failure to register cpu_dma_latency can be masked if the
second registration succeeds. Conversely, if cpu_dma_latency succeeds and
cpu_wakeup_latency fails, the function returns an error while leaving the
first misc device registered.

Return immediately on the first registration failure and deregister
cpu_dma_latency if the second registration fails.

Fixes: a4e6512a79d8 ("PM: QoS: Introduce a CPU system wakeup QoS limit")
Signed-off-by: Yuho Choi &lt;dbgh9129@gmail.com&gt;
Link: https://patch.msgid.link/20260608170748.82273-1-dbgh9129@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
cpu_latency_qos_init() registers cpu_dma_latency first and, when
CONFIG_PM_QOS_CPU_SYSTEM_WAKEUP is enabled, registers cpu_wakeup_latency
afterwards. The second registration overwrites the first return value.

As a result, a failure to register cpu_dma_latency can be masked if the
second registration succeeds. Conversely, if cpu_dma_latency succeeds and
cpu_wakeup_latency fails, the function returns an error while leaving the
first misc device registered.

Return immediately on the first registration failure and deregister
cpu_dma_latency if the second registration fails.

Fixes: a4e6512a79d8 ("PM: QoS: Introduce a CPU system wakeup QoS limit")
Signed-off-by: Yuho Choi &lt;dbgh9129@gmail.com&gt;
Link: https://patch.msgid.link/20260608170748.82273-1-dbgh9129@gmail.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device</title>
<updated>2026-06-09T01:21:31+00:00</updated>
<author>
<name>Youngjun Park</name>
<email>youngjun.park@lge.com</email>
</author>
<published>2026-03-23T16:08:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c13a0316aef5f4b73e8b4bf6943737f836d65e1d'/>
<id>c13a0316aef5f4b73e8b4bf6943737f836d65e1d</id>
<content type='text'>
Patch series "mm/swap, PM: hibernate: fix swapoff race in uswsusp by
pinning swap device", v8.

Currently, in the uswsusp path, only the swap type value is retrieved at
lookup time without holding a reference. If swapoff races after the type
is acquired, subsequent slot allocations operate on a stale swap device.

Additionally, grabbing and releasing the swap device reference on every
slot allocation is inefficient across the entire hibernation swap path.

This patch series addresses these issues:
- Patch 1: Fixes the swapoff race in uswsusp by pinning the swap device
  from the point it is looked up until the session completes.
- Patch 2: Removes the overhead of per-slot reference counting in alloc/free
  paths and cleans up the redundant SWP_WRITEOK check.


This patch (of 2):

Hibernation via uswsusp (/dev/snapshot ioctls) has a race window: after
selecting the resume swap area but before user space is frozen, swapoff
may run and invalidate the selected swap device.

Fix this by pinning the swap device with SWP_HIBERNATION while it is in
use.  The pin is exclusive, which is sufficient since hibernate_acquire()
already prevents concurrent hibernation sessions.

The kernel swsusp path (sysfs-based hibernate/resume) uses
find_hibernation_swap_type() which is not affected by the pin.  It freezes
user space before touching swap, so swapoff cannot race.

Introduce dedicated helpers:
- pin_hibernation_swap_type(): Look up and pin the swap device.
  Used by the uswsusp path.
- find_hibernation_swap_type(): Lookup without pinning.
  Used by the kernel swsusp path.
- unpin_hibernation_swap_type(): Clear the hibernation pin.

While a swap device is pinned, swapoff is prevented from proceeding.

Link: https://lore.kernel.org/20260323160822.1409904-1-youngjun.park@lge.com
Link: https://lore.kernel.org/20260323160822.1409904-2-youngjun.park@lge.com
Signed-off-by: Youngjun Park &lt;youngjun.park@lge.com&gt;
Reviewed-by: Kairui Song &lt;kasong@tencent.com&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Barry Song &lt;baohua@kernel.org&gt;
Cc: Chris Li &lt;chrisl@kernel.org&gt;
Cc: Kemeng Shi &lt;shikemeng@huaweicloud.com&gt;
Cc: Nhat Pham &lt;nphamcs@gmail.com&gt;
Cc: "Rafael J . Wysocki" &lt;rafael@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Patch series "mm/swap, PM: hibernate: fix swapoff race in uswsusp by
pinning swap device", v8.

Currently, in the uswsusp path, only the swap type value is retrieved at
lookup time without holding a reference. If swapoff races after the type
is acquired, subsequent slot allocations operate on a stale swap device.

Additionally, grabbing and releasing the swap device reference on every
slot allocation is inefficient across the entire hibernation swap path.

This patch series addresses these issues:
- Patch 1: Fixes the swapoff race in uswsusp by pinning the swap device
  from the point it is looked up until the session completes.
- Patch 2: Removes the overhead of per-slot reference counting in alloc/free
  paths and cleans up the redundant SWP_WRITEOK check.


This patch (of 2):

Hibernation via uswsusp (/dev/snapshot ioctls) has a race window: after
selecting the resume swap area but before user space is frozen, swapoff
may run and invalidate the selected swap device.

Fix this by pinning the swap device with SWP_HIBERNATION while it is in
use.  The pin is exclusive, which is sufficient since hibernate_acquire()
already prevents concurrent hibernation sessions.

The kernel swsusp path (sysfs-based hibernate/resume) uses
find_hibernation_swap_type() which is not affected by the pin.  It freezes
user space before touching swap, so swapoff cannot race.

Introduce dedicated helpers:
- pin_hibernation_swap_type(): Look up and pin the swap device.
  Used by the uswsusp path.
- find_hibernation_swap_type(): Lookup without pinning.
  Used by the kernel swsusp path.
- unpin_hibernation_swap_type(): Clear the hibernation pin.

While a swap device is pinned, swapoff is prevented from proceeding.

Link: https://lore.kernel.org/20260323160822.1409904-1-youngjun.park@lge.com
Link: https://lore.kernel.org/20260323160822.1409904-2-youngjun.park@lge.com
Signed-off-by: Youngjun Park &lt;youngjun.park@lge.com&gt;
Reviewed-by: Kairui Song &lt;kasong@tencent.com&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Barry Song &lt;baohua@kernel.org&gt;
Cc: Chris Li &lt;chrisl@kernel.org&gt;
Cc: Kemeng Shi &lt;shikemeng@huaweicloud.com&gt;
Cc: Nhat Pham &lt;nphamcs@gmail.com&gt;
Cc: "Rafael J . Wysocki" &lt;rafael@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
