The quilt patch titled
Subject: nilfs2: avoid having an active sc_timer before freeing sci
has been removed from the -mm tree. Its filename was
nilfs2-avoid-having-an-active-sc_timer-before-freeing-sci.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Edward Adam Davis <eadavis(a)qq.com>
Subject: nilfs2: avoid having an active sc_timer before freeing sci
Date: Thu, 30 Oct 2025 07:51:52 +0900
Because kthread_stop did not stop sc_task properly and returned -EINTR,
the sc_timer was not properly closed, ultimately causing the problem [1]
reported by syzbot when freeing sci due to the sc_timer not being closed.
Because the thread sc_task main function nilfs_segctor_thread() returns 0
when it succeeds, when the return value of kthread_stop() is not 0 in
nilfs_segctor_destroy(), we believe that it has not properly closed
sc_timer.
We use timer_shutdown_sync() to sync wait for sc_timer to shutdown, and
set the value of sc_task to NULL under the protection of lock
sc_state_lock, so as to avoid the issue caused by sc_timer not being
properly shutdowned.
[1]
ODEBUG: free active (active state 0) object: 00000000dacb411a object type: timer_list hint: nilfs_construction_timeout
Call trace:
nilfs_segctor_destroy fs/nilfs2/segment.c:2811 [inline]
nilfs_detach_log_writer+0x668/0x8cc fs/nilfs2/segment.c:2877
nilfs_put_super+0x4c/0x12c fs/nilfs2/super.c:509
Link: https://lkml.kernel.org/r/20251029225226.16044-1-konishi.ryusuke@gmail.com
Fixes: 3f66cc261ccb ("nilfs2: use kthread_create and kthread_stop for the log writer thread")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke(a)gmail.com>
Reported-by: syzbot+24d8b70f039151f65590(a)syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=24d8b70f039151f65590
Tested-by: syzbot+24d8b70f039151f65590(a)syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis(a)qq.com>
Cc: <stable(a)vger.kernel.org> [6.12+]
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
fs/nilfs2/segment.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/fs/nilfs2/segment.c~nilfs2-avoid-having-an-active-sc_timer-before-freeing-sci
+++ a/fs/nilfs2/segment.c
@@ -2768,7 +2768,12 @@ static void nilfs_segctor_destroy(struct
if (sci->sc_task) {
wake_up(&sci->sc_wait_daemon);
- kthread_stop(sci->sc_task);
+ if (kthread_stop(sci->sc_task)) {
+ spin_lock(&sci->sc_state_lock);
+ sci->sc_task = NULL;
+ timer_shutdown_sync(&sci->sc_timer);
+ spin_unlock(&sci->sc_state_lock);
+ }
}
spin_lock(&sci->sc_state_lock);
_
Patches currently in -mm which might be from eadavis(a)qq.com are
The quilt patch titled
Subject: scripts/decode_stacktrace.sh: fix build ID and PC source parsing
has been removed from the -mm tree. Its filename was
scripts-decode_stacktracesh-fix-build-id-and-pc-source-parsing.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Carlos Llamas <cmllamas(a)google.com>
Subject: scripts/decode_stacktrace.sh: fix build ID and PC source parsing
Date: Thu, 30 Oct 2025 01:03:33 +0000
Support for parsing PC source info in stacktraces (e.g. '(P)') was added
in commit 2bff77c665ed ("scripts/decode_stacktrace.sh: fix decoding of
lines with an additional info"). However, this logic was placed after the
build ID processing. This incorrect order fails to parse lines containing
both elements, e.g.:
drm_gem_mmap_obj+0x114/0x200 [drm 03d0564e0529947d67bb2008c3548be77279fd27] (P)
This patch fixes the problem by extracting the PC source info first and
then processing the module build ID. With this change, the line above is
now properly parsed as such:
drm_gem_mmap_obj (./include/linux/mmap_lock.h:212 ./include/linux/mm.h:811 drivers/gpu/drm/drm_gem.c:1177) drm (P)
While here, also add a brief explanation the build ID section.
Link: https://lkml.kernel.org/r/20251030010347.2731925-1-cmllamas@google.com
Fixes: 2bff77c665ed ("scripts/decode_stacktrace.sh: fix decoding of lines with an additional info")
Signed-off-by: Carlos Llamas <cmllamas(a)google.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Reviewed-by: Luca Ceresoli <luca.ceresoli(a)bootlin.com>
Cc: Breno Leitao <leitao(a)debian.org>
Cc: Catalin Marinas <catalin.marinas(a)arm.com>
Cc: Marc Rutland <mark.rutland(a)arm.com>
Cc: Mark Brown <broonie(a)kernel.org>
Cc: Matthieu Baerts <matttbe(a)kernel.org>
Cc: Miroslav Benes <mbenes(a)suse.cz>
Cc: Puranjay Mohan <puranjay(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
scripts/decode_stacktrace.sh | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
--- a/scripts/decode_stacktrace.sh~scripts-decode_stacktracesh-fix-build-id-and-pc-source-parsing
+++ a/scripts/decode_stacktrace.sh
@@ -277,12 +277,6 @@ handle_line() {
fi
done
- if [[ ${words[$last]} =~ ^[0-9a-f]+\] ]]; then
- words[$last-1]="${words[$last-1]} ${words[$last]}"
- unset words[$last] spaces[$last]
- last=$(( $last - 1 ))
- fi
-
# Extract info after the symbol if present. E.g.:
# func_name+0x54/0x80 (P)
# ^^^
@@ -294,6 +288,14 @@ handle_line() {
unset words[$last] spaces[$last]
last=$(( $last - 1 ))
fi
+
+ # Join module name with its build id if present, as these were
+ # split during tokenization (e.g. "[module" and "modbuildid]").
+ if [[ ${words[$last]} =~ ^[0-9a-f]+\] ]]; then
+ words[$last-1]="${words[$last-1]} ${words[$last]}"
+ unset words[$last] spaces[$last]
+ last=$(( $last - 1 ))
+ fi
if [[ ${words[$last]} =~ \[([^]]+)\] ]]; then
module=${words[$last]}
_
Patches currently in -mm which might be from cmllamas(a)google.com are
The quilt patch titled
Subject: mm/damon/sysfs: change next_update_jiffies to a global variable
has been removed from the -mm tree. Its filename was
mm-damon-sysfs-change-next_update_jiffies-to-a-global-variable.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Quanmin Yan <yanquanmin1(a)huawei.com>
Subject: mm/damon/sysfs: change next_update_jiffies to a global variable
Date: Thu, 30 Oct 2025 10:07:46 +0800
In DAMON's damon_sysfs_repeat_call_fn(), time_before() is used to compare
the current jiffies with next_update_jiffies to determine whether to
update the sysfs files at this moment.
On 32-bit systems, the kernel initializes jiffies to "-5 minutes" to make
jiffies wrap bugs appear earlier. However, this causes time_before() in
damon_sysfs_repeat_call_fn() to unexpectedly return true during the first
5 minutes after boot on 32-bit systems (see [1] for more explanation,
which fixes another jiffies-related issue before). As a result, DAMON
does not update sysfs files during that period.
There is also an issue unrelated to the system's word size[2]: if the
user stops DAMON just after next_update_jiffies is updated and restarts
it after 'refresh_ms' or a longer delay, next_update_jiffies will retain
an older value, causing time_before() to return false and the update to
happen earlier than expected.
Fix these issues by making next_update_jiffies a global variable and
initializing it each time DAMON is started.
Link: https://lkml.kernel.org/r/20251030020746.967174-3-yanquanmin1@huawei.com
Link: https://lkml.kernel.org/r/20250822025057.1740854-1-ekffu200098@gmail.com [1]
Link: https://lore.kernel.org/all/20251029013038.66625-1-sj@kernel.org/ [2]
Fixes: d809a7c64ba8 ("mm/damon/sysfs: implement refresh_ms file internal work")
Suggested-by: SeongJae Park <sj(a)kernel.org>
Reviewed-by: SeongJae Park <sj(a)kernel.org>
Signed-off-by: Quanmin Yan <yanquanmin1(a)huawei.com>
Cc: Kefeng Wang <wangkefeng.wang(a)huawei.com>
Cc: ze zuo <zuoze1(a)huawei.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/damon/sysfs.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
--- a/mm/damon/sysfs.c~mm-damon-sysfs-change-next_update_jiffies-to-a-global-variable
+++ a/mm/damon/sysfs.c
@@ -1552,16 +1552,17 @@ static struct damon_ctx *damon_sysfs_bui
return ctx;
}
+static unsigned long damon_sysfs_next_update_jiffies;
+
static int damon_sysfs_repeat_call_fn(void *data)
{
struct damon_sysfs_kdamond *sysfs_kdamond = data;
- static unsigned long next_update_jiffies;
if (!sysfs_kdamond->refresh_ms)
return 0;
- if (time_before(jiffies, next_update_jiffies))
+ if (time_before(jiffies, damon_sysfs_next_update_jiffies))
return 0;
- next_update_jiffies = jiffies +
+ damon_sysfs_next_update_jiffies = jiffies +
msecs_to_jiffies(sysfs_kdamond->refresh_ms);
if (!mutex_trylock(&damon_sysfs_lock))
@@ -1607,6 +1608,9 @@ static int damon_sysfs_turn_damon_on(str
}
kdamond->damon_ctx = ctx;
+ damon_sysfs_next_update_jiffies =
+ jiffies + msecs_to_jiffies(kdamond->refresh_ms);
+
repeat_call_control->fn = damon_sysfs_repeat_call_fn;
repeat_call_control->data = kdamond;
repeat_call_control->repeat = true;
_
Patches currently in -mm which might be from yanquanmin1(a)huawei.com are
mm-damon-add-a-min_sz_region-parameter-to-damon_set_region_biggest_system_ram_default.patch
mm-damon-reclaim-use-min_sz_region-for-core-address-alignment-when-setting-regions.patch
The quilt patch titled
Subject: mm/damon/stat: change last_refresh_jiffies to a global variable
has been removed from the -mm tree. Its filename was
mm-damon-stat-change-last_refresh_jiffies-to-a-global-variable.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Quanmin Yan <yanquanmin1(a)huawei.com>
Subject: mm/damon/stat: change last_refresh_jiffies to a global variable
Date: Thu, 30 Oct 2025 10:07:45 +0800
Patch series "mm/damon: fixes for the jiffies-related issues", v2.
On 32-bit systems, the kernel initializes jiffies to "-5 minutes" to make
jiffies wrap bugs appear earlier. However, this may cause the
time_before() series of functions to return unexpected values, resulting
in DAMON not functioning as intended. Meanwhile, similar issues exist in
some specific user operation scenarios.
This patchset addresses these issues. The first patch is about the
DAMON_STAT module, and the second patch is about the core layer's sysfs.
This patch (of 2):
In DAMON_STAT's damon_stat_damon_call_fn(), time_before_eq() is used to
avoid unnecessarily frequent stat update.
On 32-bit systems, the kernel initializes jiffies to "-5 minutes" to make
jiffies wrap bugs appear earlier. However, this causes time_before_eq()
in DAMON_STAT to unexpectedly return true during the first 5 minutes after
boot on 32-bit systems (see [1] for more explanation, which fixes another
jiffies-related issue before). As a result, DAMON_STAT does not update
any monitoring results during that period, which becomes more confusing
when DAMON_STAT_ENABLED_DEFAULT is enabled.
There is also an issue unrelated to the system's word size[2]: if the user
stops DAMON_STAT just after last_refresh_jiffies is updated and restarts
it after 5 seconds or a longer delay, last_refresh_jiffies will retain an
older value, causing time_before_eq() to return false and the update to
happen earlier than expected.
Fix these issues by making last_refresh_jiffies a global variable and
initializing it each time DAMON_STAT is started.
Link: https://lkml.kernel.org/r/20251030020746.967174-2-yanquanmin1@huawei.com
Link: https://lkml.kernel.org/r/20250822025057.1740854-1-ekffu200098@gmail.com [1]
Link: https://lore.kernel.org/all/20251028143250.50144-1-sj@kernel.org/ [2]
Fixes: fabdd1e911da ("mm/damon/stat: calculate and expose estimated memory bandwidth")
Signed-off-by: Quanmin Yan <yanquanmin1(a)huawei.com>
Suggested-by: SeongJae Park <sj(a)kernel.org>
Reviewed-by: SeongJae Park <sj(a)kernel.org>
Cc: Kefeng Wang <wangkefeng.wang(a)huawei.com>
Cc: ze zuo <zuoze1(a)huawei.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/damon/stat.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
--- a/mm/damon/stat.c~mm-damon-stat-change-last_refresh_jiffies-to-a-global-variable
+++ a/mm/damon/stat.c
@@ -46,6 +46,8 @@ MODULE_PARM_DESC(aggr_interval_us,
static struct damon_ctx *damon_stat_context;
+static unsigned long damon_stat_last_refresh_jiffies;
+
static void damon_stat_set_estimated_memory_bandwidth(struct damon_ctx *c)
{
struct damon_target *t;
@@ -130,13 +132,12 @@ static void damon_stat_set_idletime_perc
static int damon_stat_damon_call_fn(void *data)
{
struct damon_ctx *c = data;
- static unsigned long last_refresh_jiffies;
/* avoid unnecessarily frequent stat update */
- if (time_before_eq(jiffies, last_refresh_jiffies +
+ if (time_before_eq(jiffies, damon_stat_last_refresh_jiffies +
msecs_to_jiffies(5 * MSEC_PER_SEC)))
return 0;
- last_refresh_jiffies = jiffies;
+ damon_stat_last_refresh_jiffies = jiffies;
aggr_interval_us = c->attrs.aggr_interval;
damon_stat_set_estimated_memory_bandwidth(c);
@@ -210,6 +211,8 @@ static int damon_stat_start(void)
err = damon_start(&damon_stat_context, 1, true);
if (err)
return err;
+
+ damon_stat_last_refresh_jiffies = jiffies;
call_control.data = damon_stat_context;
return damon_call(damon_stat_context, &call_control);
}
_
Patches currently in -mm which might be from yanquanmin1(a)huawei.com are
mm-damon-add-a-min_sz_region-parameter-to-damon_set_region_biggest_system_ram_default.patch
mm-damon-reclaim-use-min_sz_region-for-core-address-alignment-when-setting-regions.patch
The quilt patch titled
Subject: mm/mremap: honour writable bit in mremap pte batching
has been removed from the -mm tree. Its filename was
mm-mremap-honour-writable-bit-in-mremap-pte-batching.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Dev Jain <dev.jain(a)arm.com>
Subject: mm/mremap: honour writable bit in mremap pte batching
Date: Tue, 28 Oct 2025 12:09:52 +0530
Currently mremap folio pte batch ignores the writable bit during figuring
out a set of similar ptes mapping the same folio. Suppose that the first
pte of the batch is writable while the others are not - set_ptes will end
up setting the writable bit on the other ptes, which is a violation of
mremap semantics. Therefore, use FPB_RESPECT_WRITE to check the writable
bit while determining the pte batch.
Link: https://lkml.kernel.org/r/20251028063952.90313-1-dev.jain@arm.com
Signed-off-by: Dev Jain <dev.jain(a)arm.com>
Fixes: f822a9a81a31 ("mm: optimize mremap() by PTE batching")
Reported-by: David Hildenbrand <david(a)redhat.com>
Debugged-by: David Hildenbrand <david(a)redhat.com>
Acked-by: David Hildenbrand <david(a)redhat.com>
Acked-by: Pedro Falcato <pfalcato(a)suse.de>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Barry Song <baohua(a)kernel.org>
Cc: Jann Horn <jannh(a)google.com>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org> [6.17+]
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/mremap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/mremap.c~mm-mremap-honour-writable-bit-in-mremap-pte-batching
+++ a/mm/mremap.c
@@ -187,7 +187,7 @@ static int mremap_folio_pte_batch(struct
if (!folio || !folio_test_large(folio))
return 1;
- return folio_pte_batch(folio, ptep, pte, max_nr);
+ return folio_pte_batch_flags(folio, NULL, ptep, &pte, max_nr, FPB_RESPECT_WRITE);
}
static int move_ptes(struct pagetable_move_control *pmc,
_
Patches currently in -mm which might be from dev.jain(a)arm.com are
The quilt patch titled
Subject: gcov: add support for GCC 15
has been removed from the -mm tree. Its filename was
gcov-add-support-for-gcc-15.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Peter Oberparleiter <oberpar(a)linux.ibm.com>
Subject: gcov: add support for GCC 15
Date: Tue, 28 Oct 2025 12:51:25 +0100
Using gcov on kernels compiled with GCC 15 results in truncated 16-byte
long .gcda files with no usable data. To fix this, update GCOV_COUNTERS
to match the value defined by GCC 15.
Tested with GCC 14.3.0 and GCC 15.2.0.
Link: https://lkml.kernel.org/r/20251028115125.1319410-1-oberpar@linux.ibm.com
Signed-off-by: Peter Oberparleiter <oberpar(a)linux.ibm.com>
Reported-by: Matthieu Baerts <matttbe(a)kernel.org>
Closes: https://github.com/linux-test-project/lcov/issues/445
Tested-by: Matthieu Baerts <matttbe(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
kernel/gcov/gcc_4_7.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/kernel/gcov/gcc_4_7.c~gcov-add-support-for-gcc-15
+++ a/kernel/gcov/gcc_4_7.c
@@ -18,7 +18,9 @@
#include <linux/mm.h>
#include "gcov.h"
-#if (__GNUC__ >= 14)
+#if (__GNUC__ >= 15)
+#define GCOV_COUNTERS 10
+#elif (__GNUC__ >= 14)
#define GCOV_COUNTERS 9
#elif (__GNUC__ >= 10)
#define GCOV_COUNTERS 8
_
Patches currently in -mm which might be from oberpar(a)linux.ibm.com are
The quilt patch titled
Subject: mm/mm_init: fix hash table order logging in alloc_large_system_hash()
has been removed from the -mm tree. Its filename was
mm-mm_init-fix-hash-table-order-logging-in-alloc_large_system_hash.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: "Isaac J. Manjarres" <isaacmanjarres(a)google.com>
Subject: mm/mm_init: fix hash table order logging in alloc_large_system_hash()
Date: Tue, 28 Oct 2025 12:10:12 -0700
When emitting the order of the allocation for a hash table,
alloc_large_system_hash() unconditionally subtracts PAGE_SHIFT from log
base 2 of the allocation size. This is not correct if the allocation size
is smaller than a page, and yields a negative value for the order as seen
below:
TCP established hash table entries: 32 (order: -4, 256 bytes, linear) TCP
bind hash table entries: 32 (order: -2, 1024 bytes, linear)
Use get_order() to compute the order when emitting the hash table
information to correctly handle cases where the allocation size is smaller
than a page:
TCP established hash table entries: 32 (order: 0, 256 bytes, linear) TCP
bind hash table entries: 32 (order: 0, 1024 bytes, linear)
Link: https://lkml.kernel.org/r/20251028191020.413002-1-isaacmanjarres@google.com
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Isaac J. Manjarres <isaacmanjarres(a)google.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt(a)kernel.org>
Reviewed-by: David Hildenbrand <david(a)redhat.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/mm_init.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/mm_init.c~mm-mm_init-fix-hash-table-order-logging-in-alloc_large_system_hash
+++ a/mm/mm_init.c
@@ -2469,7 +2469,7 @@ void *__init alloc_large_system_hash(con
panic("Failed to allocate %s hash table\n", tablename);
pr_info("%s hash table entries: %ld (order: %d, %lu bytes, %s)\n",
- tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size,
+ tablename, 1UL << log2qty, get_order(size), size,
virt ? (huge ? "vmalloc hugepage" : "vmalloc") : "linear");
if (_hash_shift)
_
Patches currently in -mm which might be from isaacmanjarres(a)google.com are
The quilt patch titled
Subject: mm/truncate: unmap large folio on split failure
has been removed from the -mm tree. Its filename was
mm-truncate-unmap-large-folio-on-split-failure.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Kiryl Shutsemau <kas(a)kernel.org>
Subject: mm/truncate: unmap large folio on split failure
Date: Mon, 27 Oct 2025 11:56:36 +0000
Accesses within VMA, but beyond i_size rounded up to PAGE_SIZE are
supposed to generate SIGBUS.
This behavior might not be respected on truncation.
During truncation, the kernel splits a large folio in order to reclaim
memory. As a side effect, it unmaps the folio and destroys PMD mappings
of the folio. The folio will be refaulted as PTEs and SIGBUS semantics
are preserved.
However, if the split fails, PMD mappings are preserved and the user will
not receive SIGBUS on any accesses within the PMD.
Unmap the folio on split failure. It will lead to refault as PTEs and
preserve SIGBUS semantics.
Make an exception for shmem/tmpfs that for long time intentionally mapped
with PMDs across i_size.
Link: https://lkml.kernel.org/r/20251027115636.82382-3-kirill@shutemov.name
Fixes: b9a8a4195c7d ("truncate,shmem: Handle truncates that split large folios")
Signed-off-by: Kiryl Shutsemau <kas(a)kernel.org>
Cc: Al Viro <viro(a)zeniv.linux.org.uk>
Cc: Baolin Wang <baolin.wang(a)linux.alibaba.com>
Cc: Christian Brauner <brauner(a)kernel.org>
Cc: "Darrick J. Wong" <djwong(a)kernel.org>
Cc: Dave Chinner <david(a)fromorbit.com>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: Hugh Dickins <hughd(a)google.com>
Cc: Johannes Weiner <hannes(a)cmpxchg.org>
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Matthew Wilcox (Oracle) <willy(a)infradead.org>
Cc: Michal Hocko <mhocko(a)suse.com>
Cc: Mike Rapoport <rppt(a)kernel.org>
Cc: Rik van Riel <riel(a)surriel.com>
Cc: Shakeel Butt <shakeel.butt(a)linux.dev>
Cc: Suren Baghdasaryan <surenb(a)google.com>
Cc: Vlastimil Babka <vbabka(a)suse.cz>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/truncate.c | 35 +++++++++++++++++++++++++++++------
1 file changed, 29 insertions(+), 6 deletions(-)
--- a/mm/truncate.c~mm-truncate-unmap-large-folio-on-split-failure
+++ a/mm/truncate.c
@@ -177,6 +177,32 @@ int truncate_inode_folio(struct address_
return 0;
}
+static int try_folio_split_or_unmap(struct folio *folio, struct page *split_at,
+ unsigned long min_order)
+{
+ enum ttu_flags ttu_flags =
+ TTU_SYNC |
+ TTU_SPLIT_HUGE_PMD |
+ TTU_IGNORE_MLOCK;
+ int ret;
+
+ ret = try_folio_split_to_order(folio, split_at, min_order);
+
+ /*
+ * If the split fails, unmap the folio, so it will be refaulted
+ * with PTEs to respect SIGBUS semantics.
+ *
+ * Make an exception for shmem/tmpfs that for long time
+ * intentionally mapped with PMDs across i_size.
+ */
+ if (ret && !shmem_mapping(folio->mapping)) {
+ try_to_unmap(folio, ttu_flags);
+ WARN_ON(folio_mapped(folio));
+ }
+
+ return ret;
+}
+
/*
* Handle partial folios. The folio may be entirely within the
* range if a split has raced with us. If not, we zero the part of the
@@ -226,7 +252,7 @@ bool truncate_inode_partial_folio(struct
min_order = mapping_min_folio_order(folio->mapping);
split_at = folio_page(folio, PAGE_ALIGN_DOWN(offset) / PAGE_SIZE);
- if (!try_folio_split_to_order(folio, split_at, min_order)) {
+ if (!try_folio_split_or_unmap(folio, split_at, min_order)) {
/*
* try to split at offset + length to make sure folios within
* the range can be dropped, especially to avoid memory waste
@@ -250,13 +276,10 @@ bool truncate_inode_partial_folio(struct
if (!folio_trylock(folio2))
goto out;
- /*
- * make sure folio2 is large and does not change its mapping.
- * Its split result does not matter here.
- */
+ /* make sure folio2 is large and does not change its mapping */
if (folio_test_large(folio2) &&
folio2->mapping == folio->mapping)
- try_folio_split_to_order(folio2, split_at2, min_order);
+ try_folio_split_or_unmap(folio2, split_at2, min_order);
folio_unlock(folio2);
out:
_
Patches currently in -mm which might be from kas(a)kernel.org are