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Author SHA1 Message Date
Vladimir Oltean
01a6586601 soc: fsl: guts: make fsl_soc_data available after fsl_guts_init()
In a future change, struct fsl_soc_data will be extended with methods
for performing RCW override.

Since this will be performed from a calling context outside
fsl_guts_init(), we need to keep track of the soc_data that we determine
at fsl_guts_init() time, so we can reference it later.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Link: https://lore.kernel.org/r/20260721231603.67865-7-vladimir.oltean@nxp.com
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
2026-08-07 06:54:23 +02:00
Ioana Ciornei
5f331a987f soc: fsl: guts: make it easier to determine on which SoC we are running
The guts driver will need to easily determine on which SoC it's running
when it will need to perform RCW override at runtime. The guts driver
knows this already because fsl_guts_init() reads the QorIQ/Layerscape
architectural System Version Register (SVR), but it doesn't save this
for later lookups.

Add a new qoriq_die enum to be used as an index in the fsl_soc_die
array. A new fsl_soc_die_match_one() function is also added so that we
can directly determine if the SVR is a match with a specific die.
The SVR value read from the DCFG CCSR is also kept in the global soc
structure so that it can be accessed when needed.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20260721231603.67865-6-vladimir.oltean@nxp.com
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
2026-08-07 06:54:23 +02:00
Ioana Ciornei
35faff569f soc: fsl: guts: add a central fsl_guts_read() function
Add a central fsl_guts_read() function which will take into account the
endianness that was already determined. No point is duplicating the
if-else statement each time we need to read a DCFG register.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20260721231603.67865-5-vladimir.oltean@nxp.com
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
2026-08-07 06:54:23 +02:00
Ioana Ciornei
c559ba052a soc: fsl: guts: add a global structure to hold state
Add the fsl_soc_guts structure in order to pass information like base
addresses, endianness etc between the init time and the runtime
operations (RCW override) which will get added in future patches.
There is no point in mapping and unmapping the DCFG CCSR space every
time we need to make a read, just map it once and keep its reference in
this new global structure.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20260721231603.67865-4-vladimir.oltean@nxp.com
[chleroy: fixed typo on 'structure' in commit message]
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
2026-08-07 06:54:22 +02:00
Ioana Ciornei
450e2f6a53 soc: fsl: guts: use a macro to encode the DCFG CCSR space
Instead of using a hardcoded value when iomapping the DCFG CCSR space,
add a new macro for it. The code will be easier to follow this way,
especially when we add support for the DCFG DCSR space as well.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20260721231603.67865-3-vladimir.oltean@nxp.com
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
2026-08-07 06:54:22 +02:00
Vladimir Oltean
d2fb943cba soc: fsl: guts: perform fsl_guts_init() error teardown in reverse order of setup
fsl_guts_init() is about to get much more complicated and the central
error handling procedure cannot scale in its current design, unless we
add a lot of "if" conditions to detect what has been allocated and what
hasn't.

Currently the code relies on the fact that kfree(NULL) is safe, but this
doesn't scale to the case where "soc_dev_attr" itself is NULL, because
this would dereference "soc_dev_attr->family" and friends of a NULL
pointer.

Convert to the more typical error handling pattern where the teardown is
in the strict reverse order of setup, and a teardown step is only called
if its corresponding setup step was executed.

At the same time, maintain the optionality of soc_dev_attr->serial_number
by not checking whether that kasprintf() has returned NULL. In the error
path, kfree(NULL) is safe, so we don't need to add an "if" condition for
it. Michael Walle has confirmed that ignoring the error was intentional,
and we preserve that:
https://lore.kernel.org/linux-phy/DK44809N7Y8I.J2Z3U4N32H0Q@kernel.org/

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Link: https://lore.kernel.org/r/20260721231603.67865-2-vladimir.oltean@nxp.com
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
2026-08-07 06:54:22 +02:00
Randy Dunlap
a1924557ed soc: fsl: dpio: fix kernel-doc typos
Correct spelling of 2 words.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Li Yang <leoyang.li@nxp.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Frank Li <Frank.Li@nxp.com>
Cc: Guanhua Gao <guanhua.gao@nxp.com>
Cc: Roy Pledge <Roy.Pledge@nxp.com>
Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Link: https://lore.kernel.org/r/20260728004938.905415-1-rdunlap@infradead.org
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
2026-08-07 06:54:22 +02:00
Randy Dunlap
29a5302f8f soc: fsl: fix kernel-doc warnings and typos
Correct spelling of "list".

Fix a kernel-doc warning by describing the nested structure completely:

include/soc/fsl/dpaa2-fd.h:52: warning: Function parameter or member 'simple' not described in 'dpaa2_fd'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Li Yang <leoyang.li@nxp.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Frank Li <Frank.Li@nxp.com>
Cc: Guanhua Gao <guanhua.gao@nxp.com>
Cc: Roy Pledge <Roy.Pledge@nxp.com>
Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Link: https://lore.kernel.org/r/20260728004924.904210-1-rdunlap@infradead.org
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
2026-08-07 06:54:22 +02:00
Pan Chuang
4b7a470f99 bus: fsl-mc: Remove redundant dev_err()
Since commit 55b48e23f5 ("genirq/devres: Add error handling in
devm_request_*_irq()"), devm_request_threaded_irq() automatically logs
detailed error messages on failure. Remove the now-redundant
driver-specific dev_err() calls.

Signed-off-by: Pan Chuang <panchuang@vivo.com>
Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Link: https://lore.kernel.org/r/20260710110930.462109-2-panchuang@vivo.com
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
2026-08-07 06:54:22 +02:00
Paul Louvel
1c351103ce soc: fsl: qe: Add support of IRQs in QE GPIO
Some QE GPIO pins have an associated interrupt line in the QE PIC to
signal state changes on the pin.

Because the GPIO controller does not perform any interrupt handling
itself, a nexus node (interrupt-map) is used to map each GPIO line
supporting IRQ to the parent QE PIC interrupt domain.

Add the to_irq() method in the corresponding GPIO controller driver,
that uses the nexus node to perform the translation.

Signed-off-by: Paul Louvel <paul.louvel@bootlin.com>
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Link: https://lore.kernel.org/r/20260708-qe-pic-gpios-v2-10-1972044cfbd1@bootlin.com
[chleroy: Added dependency on !SPARC to fix build on sparc reported by 0-day kernel robot]
Signed-off-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
2026-08-07 06:52:26 +02:00
Linus Torvalds
f9a2394a23 17 hotfixes. 15 are cc:stable. 16 are for MM.
There's a 3 patch series from Lorenzo "mm: fix UAF caused by race between
 ptdump and vmap pgtable freeing" which addresses a quite old bug in the
 ptdump code.
 
 And a 2 patch series also from Lorenzo which fixes a four year old bug in
 the huge_zero_folio handling.
 
 A 3 patch series from SJ fixes a few possible divide-by-zero issues which
 Sashiko sniffed out.  And a 2 patch series which fixes handling of the
 commit_inputs parameters.
 
 The remainder are singletons, please see their changelogs for details.
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Merge tag 'mm-hotfixes-stable-2026-08-06-18-44' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM fixes from Andrew Morton:
 "17 hotfixes.  15 are cc:stable.  16 are for MM.

  There's a patch series from Lorenzo "mm: fix UAF caused by race
  between ptdump and vmap pgtable freeing" which addresses a quite old
  bug in the ptdump code.

  And another series also from Lorenzo which fixes a four year old bug
  in the huge_zero_folio handling.

  A series from SJ fixes a few possible divide-by-zero issues which
  Sashiko sniffed out. And a series which fixes handling of the
  commit_inputs parameters.

  The remainder are singletons, please see their changelogs for details"

* tag 'mm-hotfixes-stable-2026-08-06-18-44' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mm/damon: adjust isolated pages stat for DAMOS_MIGRATE_{HOT,COLD}
  mm/damon/ops-common: putback folios on invalid migrate nid
  mm/huge_memory: initialise workingset state before folio split
  mm/page_table_check: skip special zero mappings
  mm/damon/lru_sort: skip damon_call() if ctx has not started
  mm/damon/reclaim: skip damon_call() if ctx has not started
  mm/damon/lru_sort: error out for >10000 active_mem_bp
  samples/damon/mtier: error out for zero quota goal target values
  mailmap: map old addresses to Danila Tikhonov
  mm/huge_memory: separate out CONFIG_PERSISTENT_HUGE_ZERO_FOLIO logic
  mm/huge_memory: fix huge_zero_pfn race
  MAINTAINERS: update address for Brendan Jackman
  mm/filemap: __filemap_add_folio() restore index before retrying
  microblaze: restore the page alignment of swapper_pg_dir
  arm64: remove redundant concurrent ptdump UAF mitigation
  mm/ptdump: always stabilise against page table freeing using init_mm
  mm/vmalloc: acquire init_mm lock on huge vmap to avoid ptdump UAF
2026-08-06 20:29:38 -07:00
Linus Torvalds
364465ab19 three ksmbd server fixes
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Merge tag 'v7.2-rc6-smb3-server-fixes' of git://git.samba.org/ksmbd

Pull smb server fixes from Steve French:

 - Reject Pattern_V1 payloads when Pattern_V1 support was not
   negotiated

 - Validate compression transform flags and chained mode before
   allocating the decompression buffer

 - Enforce the pre-authentication PDU size limit before allocating
   the decompression buffer, preventing compressed requests from
   bypassing the limit

* tag 'v7.2-rc6-smb3-server-fixes' of git://git.samba.org/ksmbd:
  ksmbd: apply the pre-authentication PDU limit when decompressing
  ksmbd: validate compression Flags before kvmalloc
  smb: compress: reject Pattern_V1 when not negotiated
2026-08-06 20:25:46 -07:00
Pu Lehui
2820d227ad riscv: ftrace: Fix ftrace_modify_call failure on kprobed functions
We are frequently hitting the following splat during the riscv bpf
selftests:

00000000026dc75a: expected (7c3ff297) but got (00100073)
------------[ ftrace bug ]------------
ftrace failed to modify
[<ffffffff03c44c1c>] bpf_kfunc_common_test+0x4/0x20 [bpf_testmod]
 actual:   e7:82:c2:ce
Updating ftrace call site to call a different ftrace function
ftrace record flags: 80100002
 (2)
 expected tramp: ffffffff80043904
------------[ cut here ]------------
WARNING: kernel/trace/ftrace.c:2278 at ftrace_bug+0x46e/0x4b0, CPU#1: test_progs/98
...
[<ffffffff80008f4e>] ftrace_bug+0x46e/0x4b0
[<ffffffff803d3e86>] ftrace_replace_code+0x16e/0x170
[<ffffffff803d42b6>] ftrace_modify_all_code+0x12e/0x1b8
[<ffffffff800430f4>] arch_ftrace_update_code+0x14/0x28
[<ffffffff803e0324>] ftrace_startup+0x14c/0x2a0
[<ffffffff803e133c>] ftrace_startup_subops+0x584/0x1050
[<ffffffff804500e6>] register_ftrace_graph+0x4e6/0x1018
[<ffffffff804cf9f6>] register_fprobe_ips+0xc66/0x12f8
[<ffffffff8049abe8>] bpf_kprobe_multi_link_attach+0x5d8/0xe68
[<ffffffff8050fcaa>] __sys_bpf+0x3d5a/0x47f0
[<ffffffff805107ee>] __riscv_sys_bpf+0xae/0x168
[<ffffffff80034d78>] syscall_handler+0x60/0x100
[<ffffffff8228b4f4>] do_trap_ecall_u+0x174/0x208
[<ffffffff822b69c4>] handle_exception+0x16c/0x178

After debugging, it can be triggered by similar commands below:
```
echo do_nanosleep > set_ftrace_filter
echo function > current_tracer
echo 'p do_nanosleep' > kprobe_events
echo 1 > events/kprobes/enable
echo 'f do_nanosleep' > dynamic_events
echo 1 > events/fprobes/enable
```

The reason is that attaching a kprobe to an ftrace-traced function entry
replaces its initial auipc insn with ebreak. When ftrace_modify_call
later runs, it expects auipc insn, so verification fails and triggers
ftrace_bug.

The expected auipc logic remains conceptually unchanged, and kprobe
single-stepping ensures normal execution. Therefore, if the first insn
is ebreak, bypassing the check to continue patching the jalr insn is
safe and avoids ftrace failures.

Fixes: b2137c3b6d ("riscv: ftrace: prepare ftrace for atomic code patching")
Signed-off-by: Pu Lehui <pulehui@huawei.com>
Link: https://patch.msgid.link/20260802094929.3978390-1-pulehui@huaweicloud.com
[pjw@kernel.org: fixed reproducer in commit message]
Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-08-06 21:02:56 -06:00
Jan Kara
9091c97be3 ext4: fix estimate extent index blocks in ext4_ext_index_trans_blocks()
The estimate of the number of impacted extent tree index blocks could be
one-too-low. If we modify say 2 extents, already two leaf index blocks
could be impacted, not just one the current estimate counts with. Fix
the estimate.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260805153605.166545-6-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-08-06 22:52:28 -04:00
Jan Kara
46e8e31771 ext4: fix transaction overflow during writeback
Commit 95ad8ee45c ("ext4: correct the reserved credits for extent
conversion") was correct to note that we need to reserve enough credits
for all extents possibly underlying a large folio. However it was too
eager to reduce the number of reserved credits. Extent conversion may
not only need to touch several leaf extent blocks, it may also need to
split extents - for example a single large unwritten extent may need to
be split into many small written ones in case of sparse folio dirtying.
This can thus result not only in extent leaf modifications but also in a
need to allocate new extent tree nodes. As a result the reserved
transaction credits were not sufficient in some corner cases. Use
ext4_meta_trans_blocks() for correct upper bound credit estimate.

Fixes: 95ad8ee45c ("ext4: correct the reserved credits for extent conversion")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260805153605.166545-5-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-08-06 22:52:28 -04:00
Jan Kara
25b2a7e8d4 ext4: teach ext4_meta_trans_blocks() about number of allocated extents
So far ext4_meta_trans_blocks() expects that each extent counted in
@pextents will be allocated in the transaction we estimate credits for.
This is correct for the use in ext4_chunk_trans_blocks() and
ext4_chunk_trans_extent() however the use in atomic write path
(ext4_convert_unwritten_extents_atomic() and ext4_iomap_alloc() for
IOMAP_ATOMIC) unnecessarily overestimates the number of necessary
credits as neither of them allocates any data. Add argument to
ext4_meta_trans_blocks() for number of extents that are going to be
allocated in the transaction.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260805153605.166545-4-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2026-08-06 22:52:23 -04:00
Muhammad Usama Anjum
288058d8db selftests/mm: unpoison pages in memory-failure teardown
The memory-failure tests call cleanup() only after all result checks.  A
failed ASSERT_* invokes fixture teardown and aborts the test, so it skips
cleanup() and leaves the injected page hardware-poisoned.

Invoke cleanup() from FIXTURE_TEARDOWN() instead.  Guard it with
self->injection_attempted so tests that exit before injection do not try
to unpoison a page when no injection was attempted.  Injection can poison
a page before returning an error or delivering SIGBUS, so teardown must
clean up after every injection attempt.  This runs the existing HWPoison
and HardwareCorrupted checks on both normal and assertion-failure paths.

Link: https://lore.kernel.org/20260729091127.1001179-1-usama.anjum@arm.com
Fixes: ff4ef2fbd1 ("selftests/mm: add memory failure anonymous page test")
Signed-off-by: Muhammad Usama Anjum <usama.anjum@arm.com>
Reviewed-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:27 -07:00
Jiacheng Yu
1d3897b024 mm/shmem: downgrade final i_blocks check in shmem_evict_inode() to pr_warn()
shmem_evict_inode() ends with WARN_ON(inode->i_blocks) as a final
consistency check of shmem's block accounting.  When it fires, the
inode-local counters die with the inode; what may linger is a small
residue in accounting kept outside the inode, such as per-mount or
per-user charges.  No data is lost, and no corruption follows.

On kernels running with panic_on_warn=1, this accounting inconsistency
escalates to a full machine panic, which is disproportionate to the
impact.

Downgrade the WARN_ON() to a pr_warn() that reports the inode together
with its accounting counters (i_blocks, alloced, swapped, nrpages),
keeping the inconsistency visible in the logs.

The accounting bugs this check has caught over the years -- the swapout
race described in commit 0f3c42f522 ("tmpfs: change final i_blocks BUG
to WARNING") and the error recovery race fixed in commit 267a4c76bb
("tmpfs: fix shmem_evict_inode() warnings on i_blocks") -- are real and
should still be fixed; this change only removes the disproportionate
escalation.

One way to hit this race: soft_offline_in_use_page()'s fast path drops a
clean, unmapped shmem folio via mapping_evict_folio(), where the
xas_store() and the nrpages decrement are not atomic against a concurrent
shmem_evict_inode(); the final shmem_recalc_inode() can then read the
pre-decrement nrpages, compute freed = 0, and leave one page charged. 
Same class as the races in 0f3c42f522 and 267a4c76bb, this time in the
under-count direction; reproduced on 7.2-rc4 with
madvise(MADV_SOFT_OFFLINE) racing MAP_FIXED replacement of a
shared-anonymous VMA.

[yujiacheng3@huawei.com: drop redundant casts in shmem_evict_inode() pr_warn]
  Link: https://lore.kernel.org/20260729121201.776566-1-yujiacheng3@huawei.com
Link: https://lore.kernel.org/20260728091014.3876715-1-yujiacheng3@huawei.com
Fixes: 0f3c42f522 ("tmpfs: change final i_blocks BUG to WARNING")
Signed-off-by: Jiacheng Yu <yujiacheng3@huawei.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Yongqiang Liu <liuyongqiang13@huawei.com>
Cc: Christian Brauner <brauner@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:27 -07:00
Jakov Novak
0ec282155c mm/khugepaged: replace mutex_lock/mutex_unlock usage with guard macro
Currently, khugepaged locks the khugepaged_mutex in two functions:
start_stop_khugepaged and khugepaged_min_free_kbytes_update.  Remove
mutex_lock/mutex_unlock usage in these functions and replace it with the
guard macro.  This makes the code more readable (removing a goto
statement) and makes it harder to introduce bugs in the future.  No
functional changes introduced.

Link: https://lore.kernel.org/20260730204724.16912-1-jakovnovak30@gmail.com
Signed-off-by: Jakov Novak <jakovnovak30@gmail.com>
Reviewed-by: Dev Jain <dev.jain@arm.com>
Reviewed-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:26 -07:00
Richard Chang
f276408a81 mm/zsmalloc: fix release order of locks in zs_page_migrate()
In zs_page_migrate(), locks are acquired in the following order:
  1. write_lock(&pool->lock)
  2. spin_lock(&class->lock)
  3. zspage_write_trylock(zspage)

However, upon successful page migration, they were being released in
forward acquisition (FIFO) order:
  1. write_unlock(&pool->lock)
  2. spin_unlock(&class->lock)
  3. zspage_write_unlock(zspage)

Fix the unlocking order to release locks in strict reverse (LIFO)
order of acquisition:
  3. zspage_write_unlock(zspage)
  2. spin_unlock(&class->lock)
  1. write_unlock(&pool->lock)

Releasing locks in reverse order of acquisition adheres to standard
kernel locking hygiene, prevents potential lock ordering and lockdep
inconsistencies.

Link: https://lore.kernel.org/20260728055333.421080-1-richardycc@google.com
Signed-off-by: Richard Chang <richardycc@google.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Tested-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Martin Liu <liumartin@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:26 -07:00
Sergey Senozhatsky
2f99b6fe0b Documentation: zram: remove sections numbering
Those numbers are difficult to maintain and in fact
we can refer to sections by their names (in html).

Link: https://lore.kernel.org/20260728021229.181627-1-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: SJ Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:26 -07:00
Wang Wensheng
6be12ddb52 ksm: stop iterating VMAs when ksm_test_exit returns true
In scan_get_next_rmap_item() the break statement only exits the inner
while loop, leaving remaining VMAs to be iterated even if ksm_test_exit()
returns true.  Replace it with a goto statement to avoid the unnecessary
work.

Link: https://lore.kernel.org/20260726133501.504048-1-wsw9603@163.com
Signed-off-by: Wang Wensheng <wsw9603@163.com>
Reviewed-by: Xu Xin <xu.xin16@zte.com.cn>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:25 -07:00
Kiryl Shutsemau (Meta)
41f2c0f716 mm: fold userfaultfd_rwp() to false without CONFIG_ARCH_HAS_PTE_PROTNONE
RWP tracks accesses by installing PAGE_NONE (protnone) PTEs, so its code
paths are gated on userfaultfd_rwp().  Without
CONFIG_ARCH_HAS_PTE_PROTNONE there is no PAGE_NONE -- <linux/pgtable.h>
defines it to a BUILD_BUG() stub, relying on callers folding such paths to
dead code via IS_ENABLED(CONFIG_ARCH_HAS_PTE_PROTNONE).

userfaultfd_rwp() was not a compile-time constant, so the compiler could
not fold those paths.  With an older compiler (gcc 8.5.0, sparc64) the
PAGE_NONE reference in move_pages_huge_pmd() survived to codegen:

  mm/huge_memory.c:2874: _dst_pmd = pmd_modify(_dst_pmd, PAGE_NONE);
  compiler_types.h:702: error: call to '__compiletime_assert_501'
    declared with attribute error: BUILD_BUG failed

RWP cannot exist without protnone, so return a compile-time false when
CONFIG_ARCH_HAS_PTE_PROTNONE is unset; every RWP path then folds away.

Link: https://lore.kernel.org/amcitKvUvFYr8W38@thinkstation
Signed-off-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202607250853.VaJWGLeA-lkp@intel.com/
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: James Houghton <jthoughton@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:25 -07:00
Breno Leitao
efe8f86c09 mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
migrate_pages_batch() unmaps each folio before moving it, and every
unmap runs the mmu_notifier invalidate callbacks.  On KVM hosts
try_to_migrate() ends up in kvm_mmu_notifier_invalidate_range_start() ->
tdp_mmu_zap_leafs(), which is expensive, so unmapping a large batch keeps
the CPU busy for a long time.

The loop already calls cond_resched(), but on PREEMPTION kernels that is
a no-op, and involuntary preemption is not a Tasks-RCU quiescent state.

A long batch therefore never reports a quiescent state, and the
migrating task (e.g. kcompactd) becomes a Tasks-RCU holdout, stalling the
Tasks-RCU grace period for minutes, which is common at Meta fleet:

  INFO: rcu_tasks detected stalls on tasks:
  0000000055349ecc: .. nvcsw: 1157401/1157401 holdout: 1 idle_cpu: -1/56 task:kcompactd0      state:R  running task
  Call Trace:
   tdp_mmu_zap_leafs
   tdp_mmu_next_root
   gfn_to_pfn_cache_invalidate_start
   kvm_mmu_notifier_invalidate_range_start
   __mmu_notifier_invalidate_range_start
   try_to_migrate_one
   try_to_migrate
   migrate_pages_batch
   migrate_pages
   compact_zone
   compact_node
   kcompactd
   kthread

Use cond_resched_tasks_rcu_qs() so a quiescent state is reported even
when cond_resched() does nothing.

This has also been discussed at [1]

Link: https://lore.kernel.org/20260727-kcompact-v1-1-bdfefddd6874@debian.org
Link: https://lore.kernel.org/all/amdWVTs0WKOxguxP@gmail.com/ [1]
Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:25 -07:00
Sebastian Andrzej Siewior
d56a82aa87 zram: use a custom key for each zram object
Each struct zram uses the same key for its struct lockdep_map which is
used for locking analysis.

According to Sergey the lock chains might be different if zram1 is used
for and zram2 is for ext4.  This might lead to false dead lock reports if
it mixes a zram1 chain with a zram2.  This can be avoided if each lockmap
gets its own unique key.c

Use a dynamic lock_class_key for the table_lock_map.

Link: https://lore.kernel.org/20260714141300.3945672-3-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Tested-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:25 -07:00
Sebastian Andrzej Siewior
dbb7ba9c7f zram: move lockmap to be per-zram instead per table
Patch series "zram: lockmap tweaks".


This patch (of 2):

The zram object contains an array zram_table_entry.  Each one has a `lock'
variable and each has a matching struct lockdep_map.  This mimics a struct
mutex.

It uses always the same key for all lockdep_map instances.  This makes it
look like the same lock to lockdep.  Therefore it could be reduced to have
one lockdep_map per struct zram.

Use only one struct lockdep_map per struct zram.

Link: https://lore.kernel.org/20260714141300.3945672-1-bigeasy@linutronix.de
Link: https://lore.kernel.org/20260714141300.3945672-2-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Tested-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:24 -07:00
zhaozhengzhuo
5716a333c9 selftests/mm: fix gup_longterm EINVAL error message
The gup_longterm test prints a literal "n" when PIN_LONGTERM_TEST_START
fails with EINVAL because the string is missing the newline escape
sequence.

Print a newline instead.

Link: https://lore.kernel.org/23557F4CB8CF36FF+20260724074603.1479243-1-zhaozhengzhuo@uniontech.com
Signed-off-by: zhaozhengzhuo <zhaozhengzhuo@uniontech.com>
Reviewed-by: Sarthak Sharma <sarthak.sharma@arm.com>
Reviewed-by: Dev Jain <dev.jain@arm.com>
Acked-by: David Hildenbrand (arm) <david@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:24 -07:00
Johannes Weiner
7e8756d7ad mm: page_alloc: fix non-movable reclaim storm in defrag_mode
As we deployed defrag_mode into Meta production, pressure spikes and
excessive swapping were observed on some workloads.  Tracing confirmed
that this is unmovable/reclaimable requests spinning in the allocator and
direct reclaim, causing excessive amounts of swap.

The initial plan for defrag_mode was to rely on kswapd/kcompactd to
produce blocks, and if those are overwhelmed under high pressure, let the
allocator fall back (__rmqueue_steal()) after its retry loops.  However,
that retrying results in more reclaim on some of these workloads than we'd
hoped, sometimes excessively so, spurred on by the !costly order
conditions in should_reclaim_retry().

The storms are dependent on the request type.  Reclaim will inevitably
make room in existing movable blocks, since that's where the LRU pages
live.  So if movable requests retry on reclaim, they make progress.

When non-movable requests spin in reclaim that isn't productive.  They
cannot use the individually freed pages, and the process is unlikely to
accidentally free whole blocks to meet the ALLOC_NOFRAGMENT bar.  They
spin and overreclaim excessively, which tanks performance and triggers
userspace guards like swap exhaustion or pressure based OOM.

To fix this, send non-movable requests, regardless of order, into
pageblock reclaim/compaction.  This way, they help move things along to
meet the ALLOC_NOFRAGMENT bar.  After this patch, the reclaim storms and
excess OOM rates are no longer observed in production.

The longer-term plan is still to have all requests, including the movable
ones, help make blocks to spread the cost of defragmenting more evenly and
fairly; combined with proper watermarking to reduce allocation latencies
in the common case.  However, doing this naively unearths scaling and
concurrency limitations in compaction that need to be addressed first. 
Promoting just non-movables for now is the minimally viable bug fix for
the above issue.

[brendan.jackman@linux.dev: fix try_to_compact_pages() kerneldoc]
  Link: https://lore.kernel.org/DK7NM9RPUJOD.11PNJJ5N2OBED@linux.dev
Link: https://lore.kernel.org/20260722150006.3848560-5-hannes@cmpxchg.org
Fixes: e3aa7df331 ("mm: page_alloc: defrag_mode")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: "Brendan Jackman" <brendan.jackman@linux.dev>
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Cc: Brendan Jackman <brendan.jackman@linux.dev>
Cc: David Hildenbrand <david@kernel.org>
Cc: Gregory Price <gourry@gourry.net>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:24 -07:00
Vlastimil Babka (SUSE)
aee220f565 mm: page_alloc: move capture_control to the page allocator
The compaction capturing code assumes the allocation request order and
compaction target order are the same.  That won't be true once defrag_mode
promotes sub-block allocations to pageblock-order compaction: compaction
targets the larger order, while capture should remain at the original
allocation order.

Move the capture_control to the page allocator and give it its own copies
of what the page freeing path matches against - zone, migratetype and the
allocation order - rather than reaching into compaction's live
compact_control.  __alloc_pages_direct_compact() fills in migratetype and
order, and installs and hides current->capture_control around the whole
compaction call; try_to_compact_pages() aims capc->zone at each zone while
it is being compacted.  compact_zone_order() no longer deals with capture
at all.

Pass the capture_control through try_to_compact_pages() /
compact_zone_order() in place of the bare struct page **.

No functional change.

Link: https://lore.kernel.org/20260722150006.3848560-4-hannes@cmpxchg.org
Fixes: e3aa7df331 ("mm: page_alloc: defrag_mode")
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Co-developed-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Gregory Price <gourry@gourry.net>
Cc: Brendan Jackman <brendan.jackman@linux.dev>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:24 -07:00
Johannes Weiner
1b4b697a57 mm: compaction: support non-movable compaction for pageblock requests
While trying to fix a reclaim storm in defrag_mode, I noticed that
non-movable direct compaction is extremely inefficient.

When searching for space to evacuate, compaction only allows blocks of the
same type as the incoming request.  This is to prevent migratetype
pollution, where a small non-movable request frees space in a movable
block and provokes the allocator to fall back and pollute it.

This protection is reasonable on one hand, but the downside is that it
makes non-movable direct compaction nearly useless: if we get the type
annotations right, by definition there aren't any movable pages inside the
non-movable blocks it is allowed to scan.

With defrag_mode, the goal is the production of whole blocks, which are
essentially type neutral: __rmqueue_claim() will convert them wholesale on
alloc.  This makes type mixing and pollution a non-issue.

Fix the pollution gates to take the requested order into account, and
allow whole-block requests to scan blocks of other types.

The only exception is CMA blocks.  That type is sticky and these blocks
cannot be claimed to other types.  Continue to be strict with them, and
allow only explicit ALLOC_CMA requests and kcompactd to evacuate them.

Link: https://lore.kernel.org/20260722150006.3848560-3-hannes@cmpxchg.org
Fixes: e3aa7df331 ("mm: page_alloc: defrag_mode")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Reviewed-by: Gregory Price <gourry@gourry.net>
Cc: Brendan Jackman <brendan.jackman@linux.dev>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:23 -07:00
Johannes Weiner
37864d0bf5 mm: page_alloc: __GFP_FS lockdep annotation for direct compaction
Patch series "mm: fix reclaim storms in defrag_mode", v2.

As we deployed vm.defrag_mode=1 in Meta production, some workloads
regressed with recurring pressure spikes and swap storms (which in turn
triggered userspace OOM rules on pressure and swap utilization levels).

Tracing pinned this to non-movable requests spinning and reclaiming
unproductively when kswapd/kcompactd are overwhelmed.  Direct reclaim
predominantly frees up pages in movable blocks, but those requests cannot
use that space under defrag_mode rules; and it is unlikely to free up
whole blocks incidentally for __rmqueue_claim() to work.

This series fixes it by making non-movable requests participate in
pageblock production in the allocator slowpath - meaning, they will invoke
direct reclaim and direct compaction with pageblock_order.

That requires some small-ish adjustments up front in the allocator and the
compaction code: three prep patches and the fix last.

The series has been in production against one of the affected workloads
for several weeks and restores the OOM kill rate to !defrag_mode baseline.


This patch (of 4):

A subsequent patch will have some order-0 allocations participate in
compaction under defrag_mode, to stave off extfrag events.

Since this is a sprawling expansion of entry points, and compaction can
enter filesystem paths, add lockdep annotations that catches __GFP_FS
passing errors.

Direct reclaim has had this annotation for a while, and since reclaim and
compaction are usually used in conjunction, this is unlikely to unearth
old bugs.  It's more about future proofing and peace of mind.

Link: https://lore.kernel.org/20260722150006.3848560-1-hannes@cmpxchg.org
Link: https://lore.kernel.org/20260722150006.3848560-2-hannes@cmpxchg.org
Fixes: e3aa7df331 ("mm: page_alloc: defrag_mode")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Brendan Jackman <brendan.jackman@linux.dev>
Cc: David Hildenbrand <david@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Brendan Jackman <brendan.jackman@linux.dev>
Cc: Gregory Price <gourry@gourry.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:23 -07:00
Yichong Chen
47f3cecd72 hugetlb: evaluate subpool free state while locked
unlock_or_release_subpool() drops spool->lock before calling
subpool_is_free().  However, subpool_is_free() reads fields that are
updated under spool->lock, including count, used_hpages and rsv_hpages.

Keep the free-state evaluation under the same lock that protects those
fields.  The reservation accounting and kfree() calls still happen after
dropping spool->lock.

Link: https://lore.kernel.org/20260721035207.1437935-1-chenyichong@uniontech.com
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Reviewed-by: Joshua Hahn <joshua.hahnjy@gmail.com>
Reviewed-by: Jane Chu <jane.chu@oracle.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:23 -07:00
Xuewen Wang
64a853c9a6 mm/damon: remove trailing semicolons after function definitions
Three function definitions terminate with '};' instead of '}', which is
unnecessary and inconsistent with kernel coding style:

- damon_pa_initcall() in paddr.c
- damon_va_initcall() in vaddr.c
- damos_get_some_mem_psi_total() in core.c

No functional change intended.

Link: https://lore.kernel.org/20260721135333.241106-1-sj@kernel.org
Signed-off-by: Xuewen Wang <wangxuewen@kylinos.cn>
Reviewed-by: SJ Park <sj@kernel.org>
Signed-off-by: SJ Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:23 -07:00
Jiahui Zhang
613c2d5552 mm/damon/ops-common: prevent migration fallback to non-target nodes
DAMOS_MIGRATE_{HOT,COLD} passes a target NUMA node to migrate_pages(). 
But alloc_migration_target() only treats mtc->nid as a preferred node
unless __GFP_THISNODE is set.  Hence target allocation can fall back to
another node, and migrate_pages() can report success without placing the
folio on the requested target node.

Consider a two-node tiered system where node 0 is a fast tier and node 1
is a CPU-less slow tier such as CXL memory, and the user wants to promote
hot regions from node 1 to node 0 with a command like:

  sudo damo start --ops vaddr --target_pid ${workload_pid} \
      --damos_action migrate_hot 0 \
      --damos_access_rate 70% max

Without the __GFP_THISNODE flag, when the memory allocator finds that node
0 is nearly full, it can fall back to node 1 without waking up kswapd. 
Then the pages allocated for migrate_pages() are still on node 1, and the
regions that are expected to be promoted to node 0 are only moved to
different physical pages on node 1.

Meanwhile, both the mm_migrate_pages tracepoint and DAMOS's own sz_applied
statistics (reported via the damos_stat_after_apply_interval tracepoint)
show the migrations as successful, which makes the failure practically
invisible and hard to investigate.

Running a demotion-purpose DAMOS scheme alongside the promotion scheme
does not fully avoid this either.  If demotion cannot keep up with the
promotion rate, allocation can still fall back to node 1 during promotion,
and the same misleading statistics show up.

Make DAMON's migration target allocation strict by setting __GFP_THISNODE,
so that a failed allocation on the target node is reported as a failure
instead of silently landing on a different node.  This is consistent with
alloc_misplaced_dst_folio(), alloc_demote_folio(), and with
do_move_pages_to_node(), which all use __GFP_THISNODE for migrations to an
explicit destination node.

Link: https://lore.kernel.org/20260721135607.251869-1-sj@kernel.org
Signed-off-by: Jiahui Zhang <jiahuitry@outlook.com>
Reviewed-by: SJ Park <sj@kernel.org>
Signed-off-by: SJ Park <sj@kernel.org>
Cc: Honggyu Kim <honggyu.kim@sk.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:22 -07:00
Song Hu
51fa46c364 mm/damon: update outdated comment about DAMOS filter handling
The kernel-doc comment above enum damos_filter_type states that only the
anon and memcg type filters are handled by damon_operations (and therefore
accounted as 'tried'), and that DAMON_OPS_VADDR and DAMON_OPS_FVADDR do
not support those two filter types.

Neither is accurate anymore.  damos_filter_for_ops() routes every filter
type except ADDR and TARGET to the operations layer, and the VADDR and
FVADDR operations (the latter being a copy of the former) handle all of
those types through damos_folio_filter_match() / damos_va_filter_out(). 
Update the comment to match the code.

Link: https://lore.kernel.org/20260721140011.269802-1-sj@kernel.org
Signed-off-by: Song Hu <husong@kylinos.cn>
Reviewed-by: SJ Park <sj@kernel.org>
Signed-off-by: SJ Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:22 -07:00
Sang-Heon Jeon
23e82f0223 arm64: remove early_ioremap_reset() call and __late_* macros
On arm64, __early_set_fixmap(), __late_set_fixmap() and
__late_clear_fixmap() are all __set_fixmap().  Calling
early_ioremap_reset() changes nothing.  So remove the call and the macros.

No functional change.

Link: https://lore.kernel.org/20260708170647.362562-4-ekffu200098@gmail.com
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:22 -07:00
Sang-Heon Jeon
36d7f1b62b riscv: remove unused __late_set_fixmap() and __late_clear_fixmap()
__late_set_fixmap() and __late_clear_fixmap() are only used after
early_ioremap_reset() has been called.  riscv never calls it because
__set_fixmap() works before and after paging_init().  So remove them.

No functional change.

Link: https://lore.kernel.org/20260708170647.362562-3-ekffu200098@gmail.com
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:22 -07:00
Sang-Heon Jeon
6fa0d03840 mm/early_ioremap: clarify early_ioremap_reset() semantics
Patch series "mm/early_ioremap: clarify and clean up
early_ioremap_reset()".

__late_set_fixmap() and __late_clear_fixmap() are only used after
early_ioremap_reset() has been called, but the comment above them does not
say anything about that.  So arm64, riscv and powerpc, whose
__set_fixmap() works before and after paging_init(), describe the same
situation in three different ways:

                 calls reset    defines the macros
        arm64    yes            yes
        riscv    no             yes
        powerpc  no             no

Patch 1 documents when early_ioremap_reset() needs to be called and that
only architectures calling it need to define the macros.

Patches 2 and 3 remove the unneeded riscv macros, which are unreachable,
and the arm64 reset call and macros, which change nothing.

No functional change.


This patch (of 3):

__late_set_fixmap() and __late_clear_fixmap() are only used after
early_ioremap_reset() has been called.

arm64, riscv and powerpc all have a __set_fixmap() that works before and
after paging_init(), so they do not need to call early_ioremap_reset() or
define the macros, but they describe the same situation in three different
ways:

                 calls reset    defines the macros
        arm64    yes            yes
        riscv    no             yes
        powerpc  no             no

The existing comment is vague and allows all three.  Replace it with
comments that make it clear when the reset and the macros are needed.

No functional change.

Link: https://lore.kernel.org/20260708170647.362562-1-ekffu200098@gmail.com
Link: https://lore.kernel.org/20260708170647.362562-2-ekffu200098@gmail.com
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:21 -07:00
longlong yan
9922d4ced6 selftests/mm/pagemap_ioctl: fix missing NULL checks after calloc()
The pagemap_ioctl selftest allocates memory via calloc() in several places
but does not check the return values.  If calloc() fails, the subsequent
code will dereference a NULL pointer and crash.

Additionally, in sanity_tests(), the calloc() failure check incorrectly
uses MAP_FAILED (the mmap() error constant) instead of NULL.  Since
calloc() returns NULL on failure, the check never triggers and a failed
allocation goes undetected.

Add NULL checks after each calloc() call, and fix the wrong error constant
in sanity_tests().  Use ksft_exit_fail_msg() consistent with the existing
error handling pattern in the file.

Link: https://lore.kernel.org/20260721063611.342-1-yanlonglong@kylinos.cn
Signed-off-by: longlong yan <yanlonglong@kylinos.cn>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: SJ Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:21 -07:00
longlong yan
63b4209482 selftests/mm: use MAP_FAILED for mmap error check
Replace the direct comparison with (void *)-1 with the standard MAP_FAILED
macro when checking mmap()

Link: https://lore.kernel.org/20260720063439.522-1-yanlonglong@kylinos.cn
Signed-off-by: longlong yan <yanlonglong@kylinos.cn>
Reviewed-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:21 -07:00
Dev Jain
4fe4ea4cbe mm/rmap: batch unmap file folios belonging to uffd-wp VMAs
Commit a67fe41e21 ("mm: rmap: support batched unmapping for file large
folios") extended batched unmapping for file folios.  That also required
making pte_install_uffd_wp_if_needed() support batching, but that was left
out for the time being.  Correctness was maintained by stopping batching
if the VMA the folio belongs to is marked uffd-wp.

Now that cond_install_uffd_wp_ptes() supports batching, call it with the
full batch length and allow folio_unmap_pte_batch() to batch file folios
belonging to uffd-wp VMAs.

For file folios, if the uffd-wp bit is set, unmapping converts present
PTEs into uffd-wp markers.  We must ensure that the same PTE range is not
reprocessed by the try_to_unmap_one() loop.

The page_vma_mapped_walk API ensures this: check_pte() only returns true
if any PFN in [pvmw->pfn, pvmw->pfn + nr_pages) is mapped by the PTE. 
There is no PFN underlying a uffd-wp marker PTE, so check_pte() returns
false and the walk skips ahead until it reaches a present entry again.

Link: https://lore.kernel.org/20260720065508.2695106-4-dev.jain@arm.com
Signed-off-by: Dev Jain <dev.jain@arm.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Harry Yoo <harry@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:21 -07:00
Dev Jain
4259767463 mm/memory: batch set uffd-wp markers during zapping
Enable batch setting of uffd-wp PTE markers.

The code paths passing nr > 1 to zap_install_uffd_wp_if_needed() produce
that nr through either folio_pte_batch() or swap_pte_batch(), therefore
batching is correct:

1) All PTEs belong to the same type of VMA: anonymous or non-anonymous,
   wp-armed or non-wp-armed.

2) All PTEs are either marked with uffd-wp or not marked with uffd-wp;
   the same applies to the pte_swp_uffd_any() check.

3) uffd_supports_wp_marker() is independent of the function parameters.

Use set_pte_at() in a loop instead of set_ptes(), because set_ptes()
cannot handle nonpresent to nonpresent conversion for nr_pages > 1.

Rename the helper to cond_install_uffd_wp_ptes().

Link: https://lore.kernel.org/20260720065508.2695106-3-dev.jain@arm.com
Signed-off-by: Dev Jain <dev.jain@arm.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Harry Yoo <harry@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:20 -07:00
Dev Jain
5d72b5d76d mm/memory: move pte_install_uffd_wp_if_needed() into memory.c
Patch series "Batch unmap of uffd-wp file folios", v2.

Currently, batched unmapping is supported if:

1) folio is a file folio, not belonging to uffd-wp VMA
2) folio is anonymous and not swapbacked (lazyfree), not belonging to
   uffd-wp VMA

So the cases which are not supported are

1) folio belonging to uffd-wp VMA
2) folio is anonymous and swapbacked

It is easy to see that this adds a lot of cognitive load while reading
try_to_unmap_one - we need to remember throughout whether nr_pages == 1 or
> 1.

The uffd-wp handling in try_to_unmap_one is regarding preserving the
uffd-wp state for file folios via pte_install_uffd_wp_if_needed (for anon
folio, we handle that while constructing the swap pte).

Stop special casing on uffd-wp VMAs by simply adding batching support to
pte_install_uffd_wp_if_needed.


This patch (of 3):

pte_install_uffd_wp_if_needed() has grown too large for mm_inline.h.  Move
it to memory.c.

This helper is only used inside mm/, so declare it in mm/internal.h
instead of a public header.

While at it, convert the comment to kerneldoc and rename the local
arguments from pte/pteval to ptep/pte so the pointer and PTE value are
easier to distinguish.

Link: https://lore.kernel.org/20260720065508.2695106-1-dev.jain@arm.com
Link: https://lore.kernel.org/20260720065508.2695106-2-dev.jain@arm.com
Signed-off-by: Dev Jain <dev.jain@arm.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Harry Yoo <harry@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:20 -07:00
Yichong Chen
60191388ca hugetlb: make hugepage_put_subpool() tolerate NULL
Both callers of hugepage_put_subpool() check whether the subpool pointer
is NULL before calling it.  Move the NULL check into
hugepage_put_subpool() so callers can use the helper unconditionally.

This is a follow-up cleanup after using hugepage_put_subpool() from the
hugetlbfs_fill_super() failure path.

Link: https://lore.kernel.org/20260720073841.1389354-1-chenyichong@uniontech.com
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Cc: David Hildenbrand <david@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:20 -07:00
Jinjiang Tu
39e9b8aeaa fs: stable_page_flags(): simplify KPF_IDLE handling
For KPF_IDLE, folio_test_idle() check in set_ps_flags() already handles
all config cases, so remove the duplicate code in stable_page_flags() that
deals with CONFIG_PAGE_IDLE_FLAG for the 64‑bit case.

No functional change is intended.

Link: https://lore.kernel.org/20260720033021.4091944-4-tujinjiang@huawei.com
Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Luiz Capitulino <luizcap@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Svetly Todorov <svetly.todorov@memverge.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:19 -07:00
Jinjiang Tu
c52faf27a9 fs: stable_page_flags(): use folio_test_*() helpers
Since commit 304daa8132 ("maps4: add /proc/kpageflags interface"),
/proc/kpageflags directly operates on page->flags to determine page
status.  Later, commit 1779754959 ("proc: export more page flags in
/proc/kpageflags") started using page helper functions when exposing new
flags, leading to a mix of both approaches.

For tail pages, the original code did not return corresponding status. 
commit 0a71649cb7 ("/proc/kpageflags: return KPF_SLAB for slab tail
pages") and commit 832fc1de01 ("/proc/kpageflags: return KPF_BUDDY for
"tail" buddy pages") made tail slab/buddy pages also return corresponding
status.  Then commit dee3d0bef2 ("proc: rewrite stable_page_flags()")
made all tail pages return the same status as their head page, except for
hwpoison and mapped flags.  It also cached the folio's flags and operate
on the flags directly to avoid concurrency issues if using folio_test_*()
helpers.

Since commit 476d87d6a0 ("fs: stable_page_flags(): use
snapshot_page()"), we can now safely switch to folio_test_*() helpers
instead of directly operating on flags, which is more readable and
consistent with the rest of the kernel.  Only convert cfolio-specific
flags (i.e., anon, ksm, swapcache) to folio_test_*() helpers, which
reduces redundant code.  Keep others unchanged due to they aren't
folio-specific flags or coverting them doesn't cleanup.

No functional change is intended.

Link: https://lore.kernel.org/20260720033021.4091944-3-tujinjiang@huawei.com
Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Luiz Capitulino <luizcap@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Svetly Todorov <svetly.todorov@memverge.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:19 -07:00
Jinjiang Tu
e984520724 fs: stable_page_flags(): use BIT_ULL() for KPF flags
Patch series "cleanup for stable_page_flags()", v2.

This series cleans up stable_page_flags(), see the details in the commit
messages.


This patch (of 3):

The stable_page_flags() function currently sets page flag bits using "1 <<
KPF_xxx" for various KPF_* definitions.  KPF_* may be larger than 32,
which will trigger -Wshift-count-overflow warning.  All KPF_* values
currently used in "1 << KPF_xxx" are smaller than 33, so no warning is
triggered with current code.

Replace all occurrences of "1 << KPF_*" with the BIT_ULL() macro to ensure
all shifts are performed on a 64-bit unsigned type.  This makes the code
robust, and safe for future extension.

No functional change is intended.

Link: https://lore.kernel.org/20260720033021.4091944-1-tujinjiang@huawei.com
Link: https://lore.kernel.org/20260720033021.4091944-2-tujinjiang@huawei.com
Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Zi Yan <ziy@nvidia.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Luiz Capitulino <luizcap@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Svetly Todorov <svetly.todorov@memverge.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:19 -07:00
Zenghui Yu (Huawei)
c2875056e1 docs/mm: Physical Memory: remove deferred_split_queue
deferred_split_queue was removed from struct pglist_data {} in commit
fafaeceb89 ("mm: switch deferred split shrinker to list_lru").  Remove
its description in doc as well.

Link: https://lore.kernel.org/20260721111919.22923-1-zenghui.yu@linux.dev
Signed-off-by: Zenghui Yu (Huawei) <zenghui.yu@linux.dev>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Reviewed-by: SJ Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:19 -07:00
SJ Park
c608748607 mm/damon/core: handle region split failure in apply_min_nr_regions()
damon_apply_min_nr_regions() repeatedly split each region until its size
becomes small enough to meet the user-defined low limit of the number of
regions.  The loop assumes the split operation (damon_split_region_at())
will always succeed and create the new region.  But the operation could
silently fail for memory allocation failures, for example.

If such failure happens and the region was the last region, the linked
list-based next region fetching returns invalid pointer.  As a result,
invalid memory dereference and corruption could happen.  Even if the
corner case is handled, it imposes stress to the allocator by trying split
regions for other targets.  Fix the issue by breaking all the loops for
any region split failure.

This means there could be a min_nr_regions violation.  It will only rarely
happen since the allocation is arguably too small to fail.  Even if it
happens, it is only temporal.  damon_apply_min_nr_regions() will be called
again after the aggregation interval.

The user impact of the issue should be minor, since the allocation is
arguably too small to fail.  But, it could still theoretically happen, and
the consequence is very bad.

This issue was discovered [1] by Sashiko.

Link: https://lore.kernel.org/20260719155442.88794-1-sj@kernel.org
Link: https://lore.kernel.org/20260717011834.120715-1-sj@kernel.org [1]
Fixes: b1029f29eb ("mm/damon/core: split regions for min_nr_regions")
Signed-off-by: SJ Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> # 7.1.x
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:18 -07:00
SJ Park
6c25083f7a mm/damon/ops-common: use nr_accesses moving sum for quota score
Since commit 42f994b714 ("mm/damon/core: implement scheme-specific apply
interval"), DAMOS scheme can be applied at any time.  At that time,
nr_accesses may not be fully aggregated.  But the quota prioritization
score is calculated using the not fully aggregated count.  As a result,
the performance of DAMOS could be degraded.  Fix by using
damon_nr_accesses_mvsum() instead.

The user impact of the issue is suboptimum DAMOS performance under certain
setups.  Nonetheless, the bug was there from the beginning of the setup
availability.  In other words, the suboptimum performance is the baseline
of the setup and hence it didn't cause regression.  Also the extent of the
suboptimality was not big enough to be found from users and testers. 
Still, this is a clear bug that is better to be fixed, and can be easily
fixed.

Link: https://lore.kernel.org/20260719161136.90191-1-sj@kernel.org
Fixes: 42f994b714 ("mm/damon/core: implement scheme-specific apply interval")
Signed-off-by: SJ Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> # 6.7.x
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-06 18:57:18 -07:00