llbitmap_cond_end_sync() is called with the sync thread's current sector.
That value is an exclusive progress boundary: sectors below it have
completed, but the llbitmap chunk containing it can still be in progress.
The old code converted that sector directly to the last bit passed to
BitmapActionEndsync. If resync had only advanced part-way into a large
llbitmap chunk, the in-progress chunk was marked synced and flushed before
the rest of the chunk was repaired. A later bitmap-assisted RAID1 resync
could then skip the remainder of that chunk and leave stale mirror data
behind.
This can be reproduced without editing bitmap metadata by creating a large
RAID1 with a lockless bitmap so llbitmap naturally selects a 524288-sector
chunk (with the default 128 KiB bitmap area, an array just over 16 TiB is
enough), making one mirror stale through the normal degraded write/re-add
path, and throttling resync so the daemon checkpoint runs while resync is
still inside the first chunk. On the bad kernel, bit 0 is ended early and a
stale sector later in the same chunk is skipped. With this fix, bit 0
remains Syncing until resync reaches the next chunk boundary.
Round the exclusive progress sector down to the nearest llbitmap chunk
boundary and end only chunks strictly below that boundary. Also honor the
force argument so callers that need an immediate checkpoint are not
suppressed by daemon_sleep.
Tested-by: Mykola Marzhan <mykola@meshstor.io>
Link: https://patch.msgid.link/20260802195038.164272-4-yukuai@kernel.org
Signed-off-by: Yu Kuai <yukuai@fygo.io>
llbitmap allocates its in-memory page cache and page-control structures from
paths that can already be holding MD reconfiguration or bitmap state locks.
For example, component_size_store() takes mddev_lock(), update_size() calls
the personality resize method, and llbitmap_resize() can grow the page cache
through llbitmap_prepare_resize().
Using GFP_KERNEL in those paths allows direct reclaim to enter filesystem or
block I/O while MD resize state is locked. That can recurse back into the
same array and wait on state that cannot make progress until the resize path
finishes.
Use GFP_NOIO for the llbitmap object, cached bitmap pages, page controls,
page-control arrays, and percpu_ref initialization. Leave the explicit
metadata zeroout path unchanged because it is intentional bitmap I/O rather
than reclaim-driven allocation.
Tested-by: Mykola Marzhan <mykola@meshstor.io>
Link: https://patch.msgid.link/20260802195038.164272-3-yukuai@kernel.org
Signed-off-by: Yu Kuai <yukuai@fygo.io>
llbitmap_flush() sets LLPageFlush on each bitmap page before it queues the
daemon worker. The flag tells md_llbitmap_daemon_fn() to ignore the normal
barrier_idle expiry check and clean the page immediately.
The daemon only tested LLPageFlush. Once a page had been flushed explicitly,
the flag stayed set, so later dirty bits on that page also bypassed
barrier_idle and were cleaned the next time the daemon ran. That can make a
new write look clean much earlier than the configured idle window.
Consume LLPageFlush in md_llbitmap_daemon_fn() with test_and_clear_bit() and
use the returned value for the current expiry check. The explicit flush still
forces the current daemon pass, while later writes on the same page wait for
barrier_idle again.
This can be reproduced through normal sysfs operations:
1. Create a small RAID1 with --bitmap=lockless and --assume-clean.
2. Set llbitmap/daemon_sleep=1 and llbitmap/barrier_idle=10.
3. Toggle md/array_state from active to readonly and back to active to call
llbitmap_flush() without destroying the in-memory bitmap.
4. Write one sector and read llbitmap/bits immediately, after 2 seconds,
and after 12 seconds.
On the bad kernel the dirty bit is already clean after 2 seconds. With this
change it remains dirty until the barrier_idle window expires.
Tested-by: Mykola Marzhan <mykola@meshstor.io>
Link: https://patch.msgid.link/20260802195038.164272-2-yukuai@kernel.org
Signed-off-by: Yu Kuai <yukuai@fygo.io>
The following bug has been observed with kernel 7.1.3 after adding a new
rdev to an existing RAID1 array with serialize_policy enabled:
Oops: 0002 [#1]
CPU: 0 UID: 0 PID: 19639 Comm: ext4lazyinit Not tainted 7.1.3-1-default
RIP: _raw_spin_lock_irqsave+0x27/0x50
CR2: 0000000000004960
Call Trace:
wait_for_serialization+0xb9/0x260 [raid1]
raid1_make_request+0x762/0xaff [raid1]
md_handle_request+0x1c9/0x2e0 [md_mod]
The raid1.c code calls wait_for_serialization() if the MD_SERIALIZE_POLICY
is set, and wait_for_serialization assumes that rdev->serial is
initialized. Normally this will be the case for arrays that have
the serialize_policy sysfs attribute set to 1.
But when a new rdev is added to an existing array in bind_rdev_to_array(),
the condition at mddev_create_serial_pool() causes creation of rdev->serial
to be skipped. Fix it.
Fixes: 69b00b5bb2 ("md: introduce a new struct for IO serialization")
Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Mykola Marzhan <mykola@meshstor.io>
Link: https://patch.msgid.link/20260723112741.1206836-1-mwilck@suse.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
In super_1_load(), sb->bblog_shift is an __u8 type value loaded from on-
disk superblock. It is used for badblocks API badblocks_set() by the
following sequence,
1930 rdev->badblocks.shift = sb->bblog_shift;
1931 for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) {
1932 u64 bb = le64_to_cpu(*bbp);
1933 int count = bb & (0x3ff);
1934 u64 sector = bb >> 10;
1935 sector <<= sb->bblog_shift;
1936 count <<= sb->bblog_shift;
1937 if (bb + 1 == 0)
1938 break;
1939 if (!badblocks_set(&rdev->badblocks, sector, count, 1))
1940 return -EINVAL;
1941 }
bb->bblog_shit is in range of 0-255, variable sector is 64bit width, for
an invalid bb->bblog_shit, it is possible to make sector be overflowed
by the following calculation,
1935 sector <<= sb->bblog_shift;
Then in turn when call badblocks_set() at line 1939 with the invalid
rdev->badblocks.shift set at line 1930, may result an overflow inside
_badblocks_clear() in block/badblocks.c.
Although there are many places to call badblocks APIs, the non-zero
shift value is only used in super_1_load(), other places always use 0 as
the shift value. Therefore it is unnecessary to do a general shift value
overflow check inside badblock API, and just check here as the caller.
This may avoid unnecessary check, make the badblocks API code more simple
and elegant.
Fixes: 2699b67223 ("md: load/store badblock list from v1.x metadata")
Fixes: 1726c77467 ("badblocks: improve badblocks_set() for multiple ranges handling")
Cc: stable@vger.kernel.org
Cc: Ramesh Adhikari <adhikari.resume@gmail.com>
Signed-off-by: Coly Li <colyli@fygo.io>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260720111400.2120834-1-colyli@fygo.io
Signed-off-by: Yu Kuai <yukuai@fygo.io>
Storing a memalloc_noio_save() token in mddev->noio_flags lets one task
save the token and another task restore it. With concurrent suspend sysfs
writes, task A can enter PF_MEMALLOC_NOIO, return to userspace still in
that scope, and later task B can restore A's saved token.
Avoid tying the token lifetime to mddev. Keep mddev_suspend() and
mddev_resume() only responsible for array suspension, and enter
PF_MEMALLOC_NOIO only in the MD paths that allocate memory after the array
has been suspended. Restore the token before resuming the array.
A reproducer repeatedly writes suspend_lo and suspend_hi from concurrent
workers and checks each worker's /proc/self/stat flags before and after the
sysfs write.
Link: https://github.com/chencheng-fnnas/reproducer/blob/main/repro-md-noio-token-leak.sh
Fixes: 78f57ef9d5 ("md: use memalloc scope APIs in mddev_suspend()/mddev_resume()")
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260718084218.417895-1-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
backlog_store() suspends the array before checking whether a write-mostly
device exists. If no such device exists, the error path only unlocks
reconfig_mutex and leaves the array suspended, blocking subsequent I/O.
Use mddev_unlock_and_resume() to release both states.
Fixes: 58226942ad ("md: use new apis to suspend array before mddev_create/destroy_serial_pool")
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260718034236.4119093-1-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
make_discard_request() returns without completing the bio when reshape
is in progress. Discard callers block in submit_bio_wait()
waiting for a completion that never arrives. The caller hangs in
uninterruptible sleep, and this does not resolve when reshape finishes.
Complete the bio with BLK_STS_AGAIN so userspace can retry after reshape,
consistent with the existing policy of not processing discard during
reshape.
Tested on a loop-backed RAID5 array during mdadm --grow: without this
patch, blkdiscard hangs in bio_await() and remains in uninterruptible
sleep after md reports "reshape done"; with this patch it returns
-EAGAIN instead.
Signed-off-by: Genjian Zhang <zhanggenjian@kylinos.cn>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260711161326.962336-1-zhanggenjian@126.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
origin flow:
bio_endio(master_bio); /* may drop active_io to zero */
allow_barrier(conf);
free_r10bio(r10_bio); /* reads conf->geo, returns to pool */
one scenario is:
CPU A (softirq, raid_end_bio_io) CPU B (action_store) --> reshape
================================ ===============================
bio_endio(master_bio)
md_end_clone_io
percpu_ref_put -> 0
wait_event wakeup, and,
mddev_suspend return
raid10_start_reshape:
setup_geo(&conf->geo, new)
...
mempool_destroy(old_pool)
conf->r10bio_pool = new_pool
allow_barrier(conf)
free_r10bio(r10_bio)
put_all_bios:
for (i=0; i<conf->geo.raid_disks; i++)
==> old obj, new geo, OOB
mempool_free(r10_bio, conf->r10bio_pool)
==> old-geometry obj freed into new pool
so .. fix by reorder the flow:
free_r10bio(r10_bio)
bio_endio(master_bio)
allow_barrier(conf)
raid_end_discard_bio() is exactly the same.
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Link: https://patch.msgid.link/20260711100352.425177-4-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
When reshape grows raid_disks, the pool must also switch to new geometry
object size , and allocate a new geometry size pool and replace the old.
But not for shrinking reshape, because regular I/O can still use the
prev geo for sectors that have not crossed reshape_progress yet.
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Link: https://patch.msgid.link/20260711100352.425177-3-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
raid10 needs to resize/swap r10bio_pool when reshape changes
raid_disks, and, don't let new requests keep allocating r10bio
objects from the old pool while that transition is in progress.
suspend and lock array before mddev_start_reshape(), and resume
it on exit.
Other sync_action ops are unchanged.
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Link: https://patch.msgid.link/20260711100352.425177-2-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
The badblocks core API -- badblocks_set(), badblocks_clear() and
badblocks_check() -- and the is_badblock() helper all take the range
length as sector_t. The md wrappers rdev_set_badblocks(),
rdev_clear_badblocks() and rdev_has_badblock(), however, declared the
same length as int, narrowing sector_t to int and back again in the
middle of an otherwise 64-bit clean path.
Change the sectors parameter to sector_t in these three wrappers so it
matches the core API and is_badblock(). No functional change: current
callers pass per-I/O or per-resync-chunk lengths well within int range.
This just removes a gratuitous truncation point and keeps the type
consistent end to end.
Signed-off-by: Hiroshi Nishida <nishidafmly@gmail.com>
Link: https://patch.msgid.link/20260710132329.7273-3-nishidafmly@gmail.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
raid10_write_request() drops the barrier before calling
bio_submit_split_bioset() and reacquires it afterwards. This is no
longer necessary because the split bio cannot re-enter
raid10_write_request() while the barrier is held.
The allow_barrier()/wait_barrier() pair was introduced by commit
e820d55cb9 ("md: fix raid10 hang issue caused by barrier") when
submit_flushes() called md_handle_request() directly, allowing re-entry
into raid10_write_request(). Since v5.2, submit_flushes() has instead
gone through submit_bio(), eliminating that recursion. submit_flushes()
was later removed entirely by commit b75197e86e ("md: Remove flush
handling").
Currently, raid10_write_request() is only entered from the bio
submission path, so the split bio submitted by bio_submit_split_bioset()
cannot recurse back into wait_barrier().
Remove the redundant allow_barrier()/wait_barrier() pair around
bio_submit_split_bioset().
Signed-off-by: Abd-Alrhman Masalkhi <abd.masalkhi@gmail.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260710101521.1714-5-abd.masalkhi@gmail.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
RAID10 currently handles one badblock path explicitly by failing atomic
writes with EIO. However, another badblock path can also reduce the
writable range and force the bio through bio_submit_split_bioset(),
which implicitly completes the bio with EINVAL.
Fix this by handling atomic writes in the common split check. If RAID10
determines that an atomic write would require splitting, complete the
bio with EIO.
Fixes: a1d9b4fd42 ("md/raid10: Atomic write support")
Signed-off-by: Abd-Alrhman Masalkhi <abd.masalkhi@gmail.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://patch.msgid.link/20260710101521.1714-4-abd.masalkhi@gmail.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
Restrict the RAID1 atomic write limits by setting chunk_sectors to
BARRIER_UNIT_SECTOR_SIZE so that atomic writes never straddle a barrier
unit.
A bio that passes block-layer validation may still become unserviceable
within RAID1 due to bad blocks or write-behind constraints. In the former
case, complete the bio with EIO. In the latter case, disable
write-behind rather than failing the bio with EIO.
Fixes: f2a38abf5f ("md/raid1: Atomic write support")
Fixes: a4c55c9026 ("md/raid1: simplify raid1_write_request() error handling")
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Abd-Alrhman Masalkhi <abd.masalkhi@gmail.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260710101521.1714-3-abd.masalkhi@gmail.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
remove_spares() and remove_and_add_spares() modify the array's rdev
configuration. These operations are only safe after the array has been
suspended.
md_start_sync() checks whether spare configuration changes are needed
before taking reconfig_mutex. However, the rdev state can change before
the mutex is acquired, so the initial check can become stale. In that
case, md_choose_sync_action() may remove or replace rdevs while normal
I/O is still accessing them.
The race can occur as follows:
raid10d Worker Normal IO
____________ _______________________ ______________________
raid10_write_request()
wait_blocked_dev()
set Blocked
set Faulty
Skip Faulty rdev
rrdev->nr_pending++
.repl_bio = bio
removeable_rdev = false .
array not suspended .
lock mddev goto err_handle
lock mddev (wait)
.
update sb .
clear Blocked .
.
unlock mddev .
lock mddev (acquires)
remove_spares()
removeable_rdev = true
raid10_remove_disk()
rdev = replacement
replacement = NULL
rdev_dec_pending(NULL)
unlock mddev (NULL)->nr_pending--
In this case, rdev_dec_pending() is called with a NULL pointer,
resulting in a NULL pointer dereference when attempting to decrement
nr_pending.
Fix this by suspending the array when spare configuration changes are
needed, including for non-read-write arrays, and checking again after
taking reconfig_mutex. If the array was not already suspended and a
change is now needed, release the mutex, suspend the array, and
reacquire the mutex before continuing.
Fixes: bc08041b32 ("md: suspend array in md_start_sync() if array need reconfiguration")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260628142420.1051027-1-abd.masalkhi@gmail.com?part=3
Signed-off-by: Abd-Alrhman Masalkhi <abd.masalkhi@gmail.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260708112003.474537-1-abd.masalkhi@gmail.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
REQ_NOWAIT support in md personalities that can block internally is
fundamentally incomplete. While reads can avoid some blocking paths,
write requests can still encounter cases where one mirror succeeds while
another returns -EAGAIN. At that point md cannot distinguish queue
pressure from a real device failure, so it can neither record a bad
block nor safely retry the write without REQ_NOWAIT, leaving mirrors
with divergent data.
Rather than continue advertising REQ_NOWAIT support for personalities
that cannot implement it correctly, remove it from raid1, raid10 and
raid456. Keep REQ_NOWAIT for linear and raid0, which only remap bios to
their underlying devices; stacked limits will still clear the feature if
any component device lacks REQ_NOWAIT support.
Fixes: bf2c411bb1 ("md: raid456 add nowait support")
Fixes: c9aa889b03 ("md: raid10 add nowait support")
Fixes: 5aa705039c ("md: raid1 add nowait support")
Fixes: f51d46d0e7 ("md: add support for REQ_NOWAIT")
Suggested-by: Yu Kuai <yukuai@fygo.io>
Signed-off-by: Abd-Alrhman Masalkhi <abd.masalkhi@gmail.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260628142737.1051059-1-abd.masalkhi@gmail.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
During reshape:
- reshape_request() advances rdev->recovery_offset for non-In_sync
devices locklessly.
- analyse_stripe() reads rdev->recovery_offset locklessly to decide:
a. use a replacement device to read ?
b. a device can already be treated as in-sync for the current
stripe ?
one possible scenario is:
CPU1 CPU2
reshape_request()
-> mddev->curr_resync_completed = sector_nr
-> if (!mddev->reshape_backwards)
-> rdev->recovery_offset = sector_nr
analyse_stripe(sh)
-> rdev = conf->disks[i].replacement
-> if (rdev->recovery_offset >=
sh->sector + stripe_sectors)
set_bit(R5_ReadRepl)
-> or
-> if (sh->sector + stripe_sectors <=
rdev->recovery_offset)
set_bit(R5_Insync)
And it could be:
- reading from a replacement before it is recovered far enough; or
- treating a not-yet-recovered device as in-sync for the current stripe.
Fixes: db0505d320 ("md: be cautious about using ->curr_resync_completed for ->recovery_offset")
The race report:
==================================================================
BUG: KCSAN: data-race in ops_run_io / reshape_request
write to 0xffff8bdee168b270 of 8 bytes by task 1704 on cpu 10:
reshape_request+0x1292/0x17b0
raid5_sync_request+0x815/0xa00
md_do_sync.cold+0xf8d/0x1516
[......]
read to 0xffff8bdee168b270 of 8 bytes by task 1696 on cpu 9:
ops_run_io+0xc25/0x1960
handle_stripe+0x2273/0x4570
handle_active_stripes.isra.0+0x6e0/0xa50
raid5d+0x7d5/0xb90
[......]
value changed: 0x0000000000091a00 -> 0x0000000000091b00
==================================================================
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260627102519.136940-1-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
reshape stripe lifetime:
- start reshape ==> reshape_request():
* get destination stripe,
- if need to copy source data chunks, set STRIPE_EXPANDING;
- or, if new regions past the old end of the array, zero-filled,
no need source data, set STRIPE_EXPANDING | STRIPE_READY
* get source stripe,
- set STRIPE_EXPAND_SOURCE
- handle expand stripe ==> handle_stripe():
reshape use reconstruct-write to construct stripe,
four stages:
1. prepare source data chunks for old geometry stripe
- fill source stripe data by read or compute
2. move data from old geometry source stripe to new geometry
destination stripe
- source stripe clear STRIPE_EXPAND_SOURCE
- drain data from source to destination stripe
- mark stripe chunk as R5_Expanded|R5_UPTODATE when the
drain from source chunk to destination chunk is completed
- all stripe chunks drain are completed, then mark
STRIPE_EXPAND_READY
3. calculate p/q chunks for destination stripe
- if destination stripe doesn't depends on source dstripe,
then we can clear STRIPE_EXPANDING
4. write-out to disks and release
- set R5_Wantwrite|R5_Locked, writeout to disk
- if write-out succeeded, clear STRIPE_EXPAND_READY, and
decrement reshape_stripe, call md_done_sync() to report
reshape progress.
1. cleanup the following kinds of **destination stripe**
when failed device more than max degraded:
- new regions past the old end of the array, zero-filled in place,
requires no source data.
(STRIPE_EXPANDING | STRIPE_EXPAND_READY)
- prepare source data chunks already done, and writeout failed
(STRIPE_EXPAND_READY)
2. destination stripes that need source data
(STRIPE_EXPANDING, no STRIPE_HANDLE)
- these kind of stripes sit idle in the stripe cache and are never seen
by handle_stripe(). So clean up indirectly when their source stripe
(type 3) is processed.
3. source stripes (STRIPE_EXPAND_SOURCE)
- hit handle_stripe() after their member disks are marked Faulty.
- clear STRIPE_EXPAND_SOURCE, finds and cleanup all dependent destination
stripes that were waiting for data.
- walks the source's data disks, compute the corresponding destination
sector, looks up the destination stripe, and do cleanup(clear flags,
dec counters, call md_done_sync())
Reproducer:
- Create a 4-disk RAID5 with mdadm on top of 5 disposable test disks
wrapped by dm targets.
- Add the 5th device as a spare and start a 4 -> 5 reshape.
- Wait until /sys/block/mdX/md/sync_action reports "reshape".
- Inject failures on two members so reshape exceeds max_degraded.
- After a few seconds, write "frozen" to /sys/block/mdX/md/sync_action.
Before this fix, the write blocks indefinitely.
Read-error variant:
- Use dm-dust on /dev/sd[b-f].
- Preload bad blocks on two source members, e.g. dust0 and dust1:
dmsetup message dust0 0 addbadblock <range>
dmsetup message dust1 0 addbadblock <range>
- Start reshape:
mdadm -C /dev/mdX -e 1.2 -l 5 -n 4 -c 64 \
--assume-clean /dev/mapper/dust{0..3}
mdadm --manage /dev/mdX --add /dev/mapper/dust4
mdadm --grow /dev/mdX -n 5 --backup-file=/tmp/grow.backup &
- Once reshape starts, enable the injected read failures:
dmsetup message dust0 0 enable
dmsetup message dust1 0 enable
- Then:
echo frozen > /sys/block/mdX/md/sync_action
hangs forever before the fix.
Write-error variant:
- Use dm-flakey on /dev/sd[b-f].
- Start the same 4 -> 5 reshape on flakey0..flakey4.
- Once reshape starts, switch two members, e.g. flakey3 and flakey4,
to error_writes.
- Then:
echo frozen > /sys/block/mdX/md/sync_action
hangs forever before the fix.
md_do_sync() exits its main loop on MD_RECOVERY_INTR but then blocks
forever at:
wait_event(mddev->recovery_wait,
!atomic_read(&mddev->recovery_active));
After the fix recovery_active drains to zero, md_do_sync() prints
md/raid:md0: Cannot continue operation (2/5 failed).
md: md0: reshape interrupted.
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260624075824.2601110-1-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
max_nr_stripes is updated under cache_size_mutex in the stripe cache
grow/shrink paths, while is_inactive_blocked() and
raid5_end_read_request() read it without that lock.
Use READ_ONCE() for those reads in lockless path to match the WRITE_ONCE()
updates and avoid KCSAN data race reports.
A similar issue was previously fixed in commit-id:
dfd2bf4367.
Fixes: 0009fad033 ("raid5 improve too many read errors msg by adding limits")
Fixes: 3514da58be ("md/raid5: Make is_inactive_blocked() helper")
KCSAN report:
=================
BUG: KCSAN: data-race in grow_one_stripe / is_inactive_blocked
write (marked) to 0xffff8f01f0b5a268 of 4 bytes by task 12616 on cpu 9:
grow_one_stripe+0x2d8/0x320
raid5d+0xb57/0xba0
md_thread+0x15a/0x2d0
[..........]
read to 0xffff8f01f0b5a268 of 4 bytes by task 12670 on cpu 11:
is_inactive_blocked+0x97/0xc0
raid5_get_active_stripe+0x2fd/0xa70
raid5_make_request+0x4aa/0x2940
[..........]
value changed: 0x000003b9 -> 0x000003ba
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260624024042.2561803-1-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
The patch just suppress KCSAN noise. No functional change.
KCSAN reports a race, point to update_read_sectors() update next_seq_sect vs.
read next_seq_sect.
Protect next_seq_sect and seq_start with READ_ONCE/WRITE_ONCE, otherwise,
read balance see stale sequential-read hints.
KCSAN report:
==============
BUG: KCSAN: data-race in raid1_read_request / raid1_read_request
write to 0xffff8e3a2d6736d0 of 8 bytes by task 593784 on cpu 10:
raid1_read_request+0xe5a/0x19f0
raid1_make_request+0xdf/0x1990
md_handle_request+0x4a2/0xa40
[...]
read to 0xffff8e3a2d6736d0 of 8 bytes by task 593776 on cpu 11:
raid1_read_request+0xe3f/0x19f0
raid1_make_request+0xdf/0x1990
md_handle_request+0x4a2/0xa40
[...]
value changed: 0x0000000000356368 -> 0x0000000000356370
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260623075940.2476255-1-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
kcsan detect race :
- raid5d() closes the current bitmap batch by updating
conf->seq_flush under conf->device_lock.
- __add_stripe_bio() read conf->seq_flush without that
lock when assigning sh->bm_seq.
so, protect seq_flush/seq_write consistency for multiple CPUs by
READ_ONCE()/WRITE_ONCE() under the path without held device_lock.
re-explain the stripe batch sequence number update flow:
1. sh->bm_seq declare which batch number the stripe belongs to
when perform bitmap-related write.
==> bm_seq = seq_flush+1
2. stripe be handled,
* if sh->bm_seq - conf->seq_write > 0, means the
batch stripes **newer than** the last written
batch, it cannot proceed yet, queued on bitmap_list.
* otherwise , has already proceed.
3. raid5d() `++seq_flush` to closes the current batch, means
* no more stripes join that old batch
* just-closed batch ready to write-out to disk
4. raid5d() calls bitmap hooks unplug() or writeout, then,
`++seq_write` to the same as bm_seq.
- seq_flush - for producer, to close batches.
- seq_write - for consumer, the checkpoint number.
the report:
====================================
BUG: KCSAN: data-race in __add_stripe_bio / raid5d
write to 0xffff88ba5625d470 of 4 bytes by task 82401 on cpu 0:
raid5d+0x1d9/0xba0
[.....]
read to 0xffff88ba5625d470 of 4 bytes by task 82421 on cpu 8:
__add_stripe_bio+0x332/0x400
raid5_make_request+0x6ac/0x2930
md_handle_request+0x4a2/0xa40
md_submit_bio+0x109/0x1a0
__submit_bio+0x2ec/0x390
[.....]
Fixes: 7c13edc875 ("md: incorporate new plugging into raid5.")
v1 -> v2:
- remove WRITE_ONCE(conf->seq_write) in held device_lock path.
- remove READ_ONCE(conf->seq_flush) in held device_lock path.
Signed-off-by: Chen Cheng <chencheng@fnnas.com>
Reviewed-by: Yu Kuai <yukuai@fygo.io>
Link: https://patch.msgid.link/20260622124649.1780233-1-chencheng@fnnas.com
Signed-off-by: Yu Kuai <yukuai@fygo.io>
Pull vfs fixes from Christian Brauner:
- vfs: Preserve the ACL_DONT_CACHE state in forget_cached_acl().
ACL_DONT_CACHE is meant to be a permanent opt-out from ACL caching
which FUSE relies on for servers that don't negotiate FUSE_POSIX_ACL.
The helper replaced it with ACL_NOT_CACHED, silently re-enabling the
cache, and as fuse doesn't invalidate the cache for such servers a
properly timed get_acl() returned stale ACLs. Comes with a fuse
selftest reproducing this.
- pidfs:
- Preserve PIDFD_THREAD when a thread pidfd is reopened via
open_by_handle_at(). PIDFD_THREAD shares the O_EXCL bit which
do_dentry_open() strips after the flags have been validated, so
the reopened pidfd silently became a process pidfd. Comes with a
selftest.
- Add a pidfs_dentry_open() helper so the regular pidfd allocation
path and the file handle path share the code that forces O_RDWR
and reapplies the pidfd flags that do_dentry_open() strips.
- Handle FS_IOC32_GETVERSION in the compat ioctl path.
- Make pidfs_ino_lock static.
- iomap:
- Fix the block range calculation in ifs_clear_range_dirty() so a
partial clear doesn't drop the dirty state of blocks the range
only partially covers.
- Support invalidating partial folios so a partial truncate or hole
punch with blocksize < foliosize doesn't leave stale dirty bits
behind.
- Only set did_zero when iomap_zero_iter() actually zeroed
something.
- Guard ifs_set_range_dirty() and ifs_set_range_uptodate() against
zero-length ranges where the unsigned last-block calculation
underflows and bitmap_set() writes far beyond the ifs->state
allocation.
- Don't merge ioends with different io_private values as the merge
could leak or corrupt the private data of the individual ioends.
- exec:
- Raise bprm->have_execfd only once the binfmt_misc interpreter has
actually been opened. The flag was set as soon as a matching 'O'
or 'C' entry was found. If the interpreter open failed with
ENOEXEC the exec fell through to the next binary format with
have_execfd raised but no executable staged and begin_new_exec()
NULL derefed past the point of no return.
- Fix an unsigned loop counter wrap in transfer_args_to_stack() on
nommu. An overlong argument or environment string pushes bprm->p
below PAGE_SIZE, the stop index becomes zero, and the loop never
terminates, wrapping its counter and copying garbage from in
front of the page array into the new process stack.
- Make binfmt_elf_fdpic only honour the first PT_INTERP like
binfmt_elf does. Each additional PT_INTERP overwrote the previous
interpreter, leaking the name allocation and the interpreter file
reference together with the write denial open_exec() took,
leaving the file unwritable for as long as the system runs.
- overlayfs:
- Compare the full escaped xattr prefix including the trailing dot.
An xattr like "trusted.overlay.overlayfoo" was misclassified as
an escaped overlay xattr.
- Check read access to the copy_file_range() source with the
source's mounter credentials.
- super: Thawing a filesystem whose block device was frozen with
bdev_freeze() deadlocked. Dropping the last block layer freeze
reference from under s_umount ends up in fs_bdev_thaw() which
reacquires s_umount on the same task. Pin the superblock with an
active reference instead and call bdev_thaw() without holding
s_umount.
- procfs: Return EACCES instead of success when the ptrace access check
for namespace links fails.
- afs: Use afs_dir_get_block() rather than afs_dir_find_block() for
block 0 in afs_edit_dir_remove(), matching afs_edit_dir_add().
- Push the memcg gating of ->nr_cached_objects() down into the btrfs
and shmem callbacks instead of skipping every callback during
non-root memcg reclaim. The blanket check short-circuited XFS whose
inode reclaim hook is intentionally driven from per-memcg contexts to
free memcg-charged slab.
- eventpoll: Pin files while checking reverse paths.
Since struct file became SLAB_TYPESAFE_BY_RCU a concurrent close
could free and recycle the file under the check which then took and
dropped the f_lock of whatever live file now occupies that slot.
* tag 'vfs-7.2-rc5.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (24 commits)
super: fix emergency thaw deadlock on frozen block devices
pidfs: make pidfs_ino_lock static
eventpoll: pin files while checking reverse paths
fs: push nr_cached_objects memcg gating into individual filesystems
afs: Fix afs_edit_dir_remove() to get, not find, block 0
iomap: prevent ioend merge when io_private differs
iomap: add comments for ifs_clear/set_range_dirty()
iomap: fix out-of-bounds bitmap_set() with zero-length range
iomap: fix incorrect did_zero setting in iomap_zero_iter()
iomap: support invalidating partial folios
iomap: correct the range of a partial dirty clear
fs/super: fix emergency thaw double-unlock of s_umount
pidfs: handle FS_IOC32_GETVERSION in compat ioctl
ovl: check access to copy_file_range source with src mounter creds
proc: Fix broken error paths for namespace links
pidfs: add pidfs_dentry_open() helper
selftests/pidfd: check PIDFD_THREAD survives open_by_handle_at()
pidfs: preserve thread pidfds reopened by file handle
ovl: fix trusted xattr escape prefix matching
selftests/fuse: add ACL_DONT_CACHE regression test
...
Pull spi fixes from Mark Brown:
"Just a couple of small bits for the SpacemiT driver - one small fix,
and a new compatible in the DT binding"
* tag 'spi-fix-v7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
spi: dt-bindings: spacemit: add K3 SPI compatible
spi: spacemit: Correct TX FIFO slot calculation
Pull regulator fixes from Mark Brown:
"One driver specific fix where one of the MediaTek drivers duplicated
some core code buggily, and a core fix for an ordering issue on
startup where we could end up configuring a voltage outside of
constraints due to the order in which we applied constraints"
* tag 'regulator-fix-v7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: core: clamp voltage constraints before applying apply_uV
regulator: mt6358: use regmap helper to read fixed LDO calibration
Pull char/misc driver fixes from Greg KH:
"Here are a number of small char/misc/etc driver fixes for 7.2-rc5 that
resolve a bunch of different reported issues. Included in here are:
- rust_binder error message reporting fix
- stratix10-svc firmware driver fixes
- mei driver fix
- intel_th hardware tracing driver fix
- comedi driver fix
- uio_hv_generic driver fix
- ntsync selftest fix
- nsm misc driver fix
- some MAINTAINER file updates
All of these have been in linux-next for over a week with no reported
issues"
* tag 'char-misc-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
MAINTAINERS: Update wine-devel list address
rust_binder: only print failure if error has source
intel_th: fix MSC output device reference leak
misc: nsm: pin the module while the device is open
mei: bus: access mei_device under device_lock on cleanup
misc: nsm: only unlock nsm_dev on post-lock error paths
selftests: ntsync: correct CONFIG_NTSYNC name
comedi: comedi_parport: deal with premature interrupt
uio_hv_generic: Bind to FCopy device by default
MAINTAINERS: Add Greg Kroah-Hartman to GPIB
firmware: stratix10-svc: fix teardown order in remove to prevent race
firmware: stratix10-svc: handle NO_RESPONSE in async poll
firmware: stratix10-svc: fix FCS SMC call kernel-doc
firmware: stratix10-svc: fix memory leaks and list corruption bugs
Pull staging driver fixes from Greg KH:
"Here are two small staging driver fixes for 7.2-rc5. They both resolve
some reported bugs in the rtl8723bs staging driver and have been in
linux-next for over a week with no reported issues"
* tag 'staging-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: rtl8723bs: fix OOB reads in rtw_get_wps_ie()
staging: rtl8723bs: fix inverted HT40 secondary channel offset
Pull serial driver fixes from Greg KH:
"Here are two small serial driver fixes for 7.2-rc5. They are:
- sc16is7xx get_direction() callback fix, which resolves a
user-triggerable warning in the driver
- NULL pointer dereference on some platforms using the 8250_mid
serial driver
Both have been in linux-next for over a week with no reported issues"
* tag 'tty-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: sc16is7xx: implement gpio get_direction() callback
serial: 8250_mid: Fix NULL function pointer dereference on DNV/ICX-D/SNR platforms
Pull USB fixes from Greg KH:
"Here are some small USB fixes and new device quirks and ids:
- usb storage quirk added
- new usb serial device ids added
- usb-serial device name leak and other bug fixes
- small xhci driver fixes
- normal batch of typec driver fixes for reported issues
- usb-atm much-reported-by-syzbot fix for firmware download races
- sysfs BOS device removal race fix
- lots of usb gadget driver fixes for reported issues
- other small USB driver fixes for other reported problems
All of these have been in linux-next this past week, many of them much
longer"
* tag 'usb-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (30 commits)
usb: typec: ucsi: Correct teardown ordering in ucsi_init() error path
USB: serial: io_edgeport: cap received transmit credits
USB: serial: option: add TDTECH MT5710-CN
USB: serial: io_ti: reject oversized boot-mode firmware
USB: serial: mxuport: validate firmware header size
usb: atm: ueagle-atm: reject descriptors that confuse probe and disconnect
usb: typec: ucsi: yoga_c630: Remove redundant duplicate altmode handling
usb: typec: ucsi: Add duplicate detection to nvidia registration path
usb: typec: ucsi: Detect and skip duplicate altmodes from buggy firmware
usb: gadget: dummy_hcd: prevent fifo_req reuse during giveback
usb: chipidea: fix usage_count leak when autosuspend_delay is negative
usb: core: sysfs: add lock to bos_descriptors_read()
usb: musb: omap2430: Do not put borrowed of_node in probe
usb: core: port: Deattach Type-C connector on component unbind
USB: storage: add NO_ATA_1X quirk for Longmai USB Key
USB: serial: ftdi_sio: add support for E+H FXA291
USB: serial: keyspan_pda: fix data loss on receive throttling
usb: gadget: printer: fix infinite loop in printer_read()
usb: gadget: f_midi: cancel pending IN work before freeing the midi object
usb: gadget: udc: bdc: free IRQ and drain func_wake_notify before teardown
...
Pull tracing fixes from Steven Rostedt:
- Move rb_desc->nr_page_va before updating dynamic array
The rb_descr->page_va is a dynamic array counted by nr_page_va. But
the updating of the page_va[] is done before the nr_page_va is
incremented causing a build with CONFIG_UBSAN_BOUNDS to flag it as an
overflow.
Move the increment of the counted by value before the array element
is updated.
- Propagate errors from remote event bulk updates
The return value of trace_remote_enable_event() was not being checked
by remote_events_dir_enable_write() where it would silently fail.
Have it check the return value and propagate that back up to user
space.
- Fix resource leak on mmiotrace trace_pipe close
The mmiotrace tracer was created in 2008 before the trace_pipe had a
close callback to allow tracers to do clean up from trace_pipe open.
The trace_pipe close cleanup callback was added in 2009 but the
mmiotrace tracer was not updated. It had a hack to do the cleanup in
the read call, where it may leak if user space did not read the
entire buffer.
Add a callback to mmiotrace trace_pipe close do to the cleanup
properly.
- Fix a possible NULL pointer dereference in the mmiotrace tracer
If the mmio_pipe_open() fails to find a PCI device, it will set the
hiter->dev pointer to NULL. The read function will blindly
dereference that pointer. Fix the read call to check to see if that
pointer is populated before dereferencing it.
- Fix union collision of module and refcnt for dynamic events
In 'struct trace_event_call', the 'module' pointer and the 'refcnt'
atomic variable share the same memory space in a union. The filter on
module logic only checked if the 'module' was set to determine if the
event belonged to the module. As dynamic events are always builtin,
it doesn't need the 'module' field of the structure and used a
refcount. But the module filtering logic would then mistaken these
dynamic events as a module and call module_name(event->module) on it.
Add a check to see if the event is a dynamic event and if so, do not
check it for being part of the given module.
- Reset the top level buffer in selftests before running instances
The ftracetest selftest initializes each instance before executing
the tests. But it does not reset the top level buffer. Dynamic events
are only added and removed by the top level so any left over dynamic
events will not be removed by the reset in the instances.
Left over dynamic events can cause the tests to incorrectly fail.
Reset the top level buffer before running the instances.
- Make the context_switch counter 64 bit
The code to read user space for a system call trace event or for a
trace_marker will disable migration, enable preemption, read user
space into a per CPU buffer, disable preemption and enable migration
again. It checks if the per CPU context switch counter to see if it
changed, and if it did not, it would know that the per CPU buffer was
not touched by another task.
But the save counter was 32 bit and it would compare it to the 64 bit
context_switch variable. A long running system could have the
context_switch variable greater that 1<<32 in which case the compare
will always fail. The compare will promote the 32 bit int saved value
to 64 bit and compare it to the full 64 bit counter. Since the top 32
bits of the saved value was zero, it would never match.
- Fix a use-after-free of the event_enable trigger
The event_enable trigger allows for enabling one event when another
event is triggered. When the trigger is removed, it must go through a
synchronization phase to make sure it is not triggered again. The
trigger itself is delayed by the "bulk delay" logic that was recently
added. But the code that frees the event_enable data used to rely on
the trigger code to do the synchronization. Now that the code uses
the call RCU functions (and a workqueue), that delay no longer is
there.
Add a callback private_data_free() function that allows triggers to
clean up data after the synchronization phase has completed.
- Move the module_ref counter into the delay callback
Since an event of the event_enable trigger can enable an event for a
module, it ups the module ref count for that event's module. This
prevents the event from trying to enable an event that no longer
exists and cause a use-after-free bug.
The ref counter was set back down when the trigger was removed but
not after thy synchronization phase. This could lead to the module
data being accessed after module was unloaded.
Move the module ref decrement into the private_data_free() callback
of the event_enable trigger.
- Add mutex to protect parser in ftrace filtering
The set_ftrace_filter file uses a parsing descriptor that is
allocated at open and modified by writes. If multiple threads were to
write to the descriptor at the same time, it can corrupt the parser.
Add a mutex around the modifications of the parser descriptor.
- Fix possible corruption in perf syscall tracing
The perf system call trace events can now read user space. To do so,
the reads of user space enable preemption and disables it again.
During this time that preemption is enabled, the task can migrate.
The perf event list head is assigned via a per CPU pointer. It is
done before the user space part is called. If the user space reading
migrates the task to another CPU, then the head pointer is no longer
valid.
Re-assign the head pointer after the reading of user space to keep it
using the correct data.
* tag 'trace-v7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: perf: Fix stale head for perf syscall tracing
ftrace: Add global mutex to serialize trace_parser access
tracing: Delay module ref count for "enable_event" trigger
tracing: Fix use-after-free freeing trigger private data
tracing: Fix context switch counter truncation
selftests/ftrace: Reset triggers at top level before instance loop
tracing: Fix union collision of module and refcnt for dynamic events
tracing: Fix mmiotrace possible NULL dereferencing of hiter->dev
tracing: Fix resource leak on mmiotrace trace_pipe close
tracing: Propagate errors from remote event bulk updates
tracing/remotes: Fix page_va[] access before counter update in trace_remote_alloc_buffer()
Pull m68knommu fix from Greg Ungerer:
- fix broken local SoC IO accesses for ColdFire
* tag 'm68knommu-fixes-on-top-off-7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68k: coldfire: fix breakage of missed IO access update
Pull x86 fix from Ingo Molnar:
- Disable jump/lookup tables in the x86 boot decompressor code
a bit more widely, because newer versions of LLVM started
optimizing it a bit better and introduced run-time relocations
in PIE code (Nathan Chancellor)
* tag 'x86-urgent-2026-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot/compressed: Disable jump tables
do_thaw_all_callback() calls bdev_thaw() while holding sb->s_umount
exclusively. If the block device was frozen via bdev_freeze() dropping
the last block layer freeze reference calls fs_bdev_thaw() which
reacquires s_umount:
do_thaw_all_callback(sb)
super_lock_excl(sb) # holds sb->s_umount
bdev_thaw(sb->s_bdev)
mutex_lock(&bdev->bd_fsfreeze_mutex)
# bd_fsfreeze_count drops 1 -> 0
bd_holder_ops->thaw == fs_bdev_thaw
get_bdev_super(bdev)
bdev_super_lock(bdev, true)
super_lock(sb, true)
down_write(&sb->s_umount) # same task: deadlock
The emergency thaw worker deadlocks against itself holding both
s_umount and bd_fsfreeze_mutex. That fscks any subsequent unmount,
freeze, or thaw of that filesystem and block device.
[ 81.878470] sysrq: Show Blocked State
[ 81.880140] task:kworker/0:1 state:D stack:0 pid:11 tgid:11 ppid:2 task_flags:0x4208060 flags:0x00080000
[ 81.884876] Workqueue: events do_thaw_all
[ 81.886656] Call Trace:
[ 81.887759] <TASK>
[ 81.888763] __schedule+0x579/0x1420
[ 81.890372] schedule+0x3a/0x100
[ 81.891794] schedule_preempt_disabled+0x15/0x30
[ 81.893848] rwsem_down_write_slowpath+0x1ea/0x900
[ 81.895191] ? __pfx_do_thaw_all_callback+0x10/0x10
[ 81.896528] down_write+0xbd/0xc0
[ 81.897505] super_lock+0x91/0x180
[ 81.898457] ? __mutex_lock+0xa99/0x1140
[ 81.900748] ? __mutex_unlock_slowpath+0x1f/0x400
[ 81.902069] bdev_super_lock+0x5b/0x150
[ 81.903132] get_bdev_super+0x10/0x60
[ 81.904042] fs_bdev_thaw+0x23/0xf0
[ 81.904755] bdev_thaw+0x82/0x100
[ 81.905484] do_thaw_all_callback+0x2c/0x50
[ 81.906298] __iterate_supers+0x5d/0x130
[ 81.907067] do_thaw_all+0x20/0x40
[ 81.907739] process_one_work+0x206/0x5e0
[ 81.908545] worker_thread+0x1e2/0x3c0
[ 81.909339] ? __pfx_worker_thread+0x10/0x10
[ 81.910171] kthread+0xf4/0x130
[ 81.910799] ? __pfx_kthread+0x10/0x10
[ 81.911528] ret_from_fork+0x2e2/0x3b0
[ 81.912259] ? __pfx_kthread+0x10/0x10
[ 81.913010] ret_from_fork_asm+0x1a/0x30
[ 81.913806] </TASK>
bdev_super_lock() even documents the violated requirement with
lockdep_assert_not_held(&sb->s_umount).
Acquiring bd_fsfreeze_mutex under s_umount also inverts the
bd_fsfreeze_mutex vs. s_umount ordering established by
bdev_{freeze,thaw}() and can thus ABBA against a concurrent block-layer
freeze even when the recursive path isn't hit.
Fix this by not holding s_umount around the bdev_thaw() loop at all. Pin
the superblock with an active reference instead as
filesystems_freeze_callback() does. The active reference keeps the
superblock from being shut down and so ->s_bdev stays valid without
holding s_umount. The block-layer-held freeze is dropped by
fs_bdev_thaw() with FREEZE_MAY_NEST | FREEZE_HOLDER_USERSPACE exactly as
a regular unfreeze would and thaw_super_locked() handles
filesystem-level freezes as before.
The emergency thaw path has deadlocked like this in one form or
another for a long long time but the current exclusively-held
shape dates back to commit [1] where thaw_bdev() already ended in
thaw_super() with s_umount held by do_thaw_all_callback().
Fixes: 08fdc8a013 ("buffer.c: call thaw_super during emergency thaw") [1]
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260723-work-super-emergency_thaw-v1-1-7c315c600245@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Pull rust fixes from Miguel Ojeda:
"Toolchain and infrastructure:
- 'zerocopy' crates: update to v0.8.54 to fix a modpost error under
'CONFIG_CC_OPTIMIZE_FOR_SIZE=y'.
There are actually two updates in the PR: the one to v0.8.52 is
fairly large and was originally not intended for a fixes PR, but the
actual fix landed in the v0.8.54 one. Thus I included both here.
The v0.8.52 update includes two things upstream added for us:
'--cfg no_fp_fmt_parse' to avoid a local workaround, and the new
'most_traits' feature.
The good news is that, after these updates, the delta with upstream
is now trivial: only an identifier prefix change and the SPDX
parentheses.
- Fix an objtool warning by adding one more 'noreturn' function for
Rust 1.99.0 (expected 2026-10-01).
- Clean up new 'semicolon_in_expressions_from_macros' lint errors for
Rust 1.99.0 (expected 2026-10-01). The lint can be allowed, but it
will be a hard error at some point in the future anyway, so clean it
up now.
- Locally allow new 'suspicious_runtime_symbol_definitions' lint for
Rust 1.98.0 (expected 2026-08-20).
- Globally allow 'clippy::unwrap_or_default' lint since it relies on
optimizations -- under 'CONFIG_CC_OPTIMIZE_FOR_SIZE=y' it does not
work well.
'kernel' crate:
- 'time' module: fix 'Delta::as_micros_ceil()' to round negative values
correctly"
* tag 'rust-fixes-7.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
rust: time: fix as_micros_ceil() to round correctly for negative Delta
rust: device: avoid trailing ; in printing macros
objtool/rust: add one more `noreturn` Rust function for Rust 1.99.0
rust: zerocopy: update to v0.8.54
rust: zerocopy: update to v0.8.52
rust: allow `clippy::unwrap_or_default` globally
rust: allow `suspicious_runtime_symbol_definitions` lint for Rust >= 1.98
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Update header copies of kernel headers, including const.h, fs.h,
perf_event.h, gfp_types.h, kvm.h, cpufeatures.h, rtnetlink.hp,
msr-index.h, drm.h and socket.h
- Add some build files related to BPF skels to .gitignore
* tag 'perf-tools-fixes-for-v7.2-1-2026-07-25' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools:
tools headers: Sync KVM headers with the kernel sources
tools headers: Sync UAPI linux/fs.h with the kernel sources
perf beauty: Update copy of linux/socket.h with the kernel sources
tools headers: Sync UAPI drm/drm.h with kernel sources
tools arch x86: Sync the msr-index.h copy with the kernel sources
tools headers x86 cpufeatures: Sync with the kernel sources
tools headers: Sync linux/gfp_types.h with the kernel sources
tools headers UAPI: Sync linux/rtnetlink.h with the kernel sources
tools headers UAPI: Sync linux/const.h with the kernel sources
perf bench bpf: Add missing .gitignore file
Pull firewire fix from Takashi Sakamoto:
"Fix a bug in unit driver for RFC 2734 IPv4 over IEEE 1394.
The driver failed to reassemble a complete datagram when it was stored
across multiple buffer ranges in the list. Ruoyu Wang reported and
fixed it"
* tag 'firewire-fixes-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
firewire: net: Fix fragmented datagram reassembly
Pull LoongArch fixes from Huacai Chen:
- fix build warnings and errors
- move jump_label_init() before parse_early_param()
- retrieve CPU package ID from PPTT when available
- fix some bugs kgdb, BPF JIT and laptop platform driver bugs
* tag 'loongarch-fixes-7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
platform/loongarch: laptop: Explicitly reset bl_powered state when suspend
platform/loongarch: laptop: Stop setting acpi_device_class()
LoongArch: BPF: Fix memory leak in bpf_jit_free()
LoongArch: BPF: Zero-extend signed ALU32 div/mod results
LoongArch: Fix oops during single-step debugging
LoongArch: Fix address space mismatch in kexec command line lookup
LoongArch: Retrieve CPU package ID from PPTT when available
LoongArch: Move jump_label_init() before parse_early_param()
LoongArch: Fix build errors due to wrong instructions for 32BIT
LoongArch: Increase TASK_STRUCT_OFFSET up to 2040 for 32BIT
Pull block fixes from Jens Axboe:
- Fix a ublk recovery hang, where END_USER_RECOVERY without a
successful START_USER_RECOVERY could be satisfied by a stale
completion latch
- Fix a stack out-of-bounds read in the CDROMVOLCTRL ioctl
- MAINTAINERS email address update for Roger Pau Monne
* tag 'block-7.2-20260724' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
MAINTAINERS: update my email address
cdrom: fix stack out-of-bounds read in CDROMVOLCTRL
ublk: wait on ublk_dev_ready() instead of ub->completion
Pull io_uring fixes from Jens Axboe:
- Fix a missing ERESTARTSYS conversion in the read paths, which got
messed up back when some code consolidation was done for read
multishot support
- zcrx UAPI rename, dropping the abbreviated "notif" naming in favor of
"event" for consistency and to be less ambiguous for users. This was
added for 7.2, so let's rename it while we still can. No functional
or code changes, just a strict rename
* tag 'io_uring-7.2-20260724' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
io_uring/zcrx: rename notif to event
io_uring/zcrx: rename ZCRX_NOTIF_NO_BUFFERS
io_uring/zcrx: drop "notif" from stats struct names
io_uring/rw: fix missing ERESTARTSYS conversion in read paths
In ftrace, the trace_parser structure is allocated and initialized when
a trace file is opened, and is subsequently used across write and release
handlers to parse user input.
The affected handler paths and their specific functions are:
- Open paths: ftrace_regex_open(), ftrace_graph_open()
- Write paths: ftrace_regex_write(), ftrace_graph_write()
- Release paths: ftrace_regex_release(), ftrace_graph_release()
If userspace opens a trace file descriptor and shares it across multiple
threads, concurrent write calls will race on the parser's internal state,
specifically the 'idx', 'cont', and 'buffer' fields, leading to corrupted
input or undefined behavior.
Fix this by adding a global mutex, parser_lock, to serialize all access
to trace_parser across write and release paths, preventing concurrent
corruption of parser state.
Fixes: e704eff3ff ("ftrace: Have set_graph_function handle multiple functions in one write")
Fixes: 689fd8b65d ("tracing: trace parser support for function and graph")
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260725024721.1983675-1-wutengda@huaweicloud.com
Signed-off-by: Tengda Wu <wutengda@huaweicloud.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull smb server fixes from Steve French:
"This contains eight ksmbd fixes covering POSIX ACL handling, SMB
signing enforcement, DACL parsing and construction hardening, session
lifetime handling, and validation of malformed transform and
compressed SMB2 requests:
- preserve inherited POSIX ACL mask when creating objects.
- enforce the session signing requirement for plaintext SMB requests.
- harden DACL/ACE processing against size overflows, incomplete ACE
copies, and undersized SIDs.
- defer teardown of a previous session until NTLM authentication
succeeds.
- reject undersized encryption-transform and decompressed SMB2
requests before they can reach normal SMB2 request processing"
* tag 'v7.2-rc4-smb3-server-fixes' of git://git.samba.org/ksmbd:
ksmbd: reject undersized decompressed SMB2 requests
ksmbd: validate minimum PDU size for transform requests
ksmbd: defer destroy_previous_session() until after NTLM authentication
ksmbd: validate ACE size against SID sub-authorities
ksmbd: restore DACL size on check_add_overflow() to avoid malformed ACL
ksmbd: bound DACL dedup walk to copied ACEs
ksmbd: enforce signing required by the session
ksmbd: preserve VFS inherited POSIX ACL mask
Pull bpf fixes from Eduard Zingerman:
- Fix tcp_bpf_sendmsg() error path mistaking a concurrently-freed
sk_psock->cork for the local temporary message and freeing it again
(Chengfeng Ye)
- Reject passing scalar NULL to nonnull arg of a global subprog.
Previously the verifier did not account for the cases directly
passing scalars to a global subprog, e.g.: 'global_func(0);' would
pass even if 'global_func' argument was marked nonnull (Amery Hung)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf, sockmap: Fix cork use-after-free in tcp_bpf_sendmsg()
selftests/bpf: Test passing scalar NULL to nonnull global subprog
bpf: Reject passing scalar NULL to nonnull arg of a global subprog
Triggers are now delayed from freeing, but can still be triggered until
after the RCU grace period has ended. The freeing of the enable_event data
is put into the private_data_free() callback, but the put of the module
refcount is done immediately.
It is possible that if a module is removed that has an event that would
enable (or disable) it is still active, it can read the data of the module
after it is removed causing a use-after-free bug.
Move the trace_event_put_ref() that releases the module into the delayed
callback so that the module can not be removed until any reference to its
events are finished.
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260724132415.1b5005db@gandalf.local.home
Reported-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260724030523.19081-1-devnexen%40gmail.com
Fixes: 61d445af0a ("tracing: Add bulk garbage collection of freeing event_trigger_data")
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Commit 61d445af0a ("tracing: Add bulk garbage collection of freeing
event_trigger_data") moved the kfree() of event_trigger_data to a kthread
that runs tracepoint_synchronize_unregister() before freeing. That removed
the synchronization the trigger .free callbacks used to get implicitly and
inline from trigger_data_free().
event_hist_trigger_free(), event_hist_trigger_named_free() and
event_enable_trigger_free() free their satellite data (hist_data, cmd_ops,
enable_data) right after trigger_data_free() returns. With the
synchronization now deferred to the kthread, a concurrent tracepoint
handler can still reach that data through the list_del_rcu()'d trigger,
causing a use-after-free.
The histogram teardown must stay synchronous: remove_hist_vars() and
unregister_field_var_hists() have to detach a synthetic event from the
histogram before the trigger-removal write returns, otherwise a following
command races in and the synthetic-event removal fails with -EBUSY, as the
trigger-synthetic-eprobe.tc selftest catches. Make those callbacks wait
with the correct barrier - tracepoint_synchronize_unregister(), matching
the free kthread - before freeing.
The enable trigger has no such synchronous requirement, and a blocking
synchronize there would re-serialize the path that commit deliberately
deferred. Give it an optional private_data_free() callback that the free
kthread runs after its grace period, and free enable_data from there.
Link: https://patch.msgid.link/20260724030523.19081-1-devnexen@gmail.com
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Fixes: 61d445af0a ("tracing: Add bulk garbage collection of freeing event_trigger_data")
Signed-off-by: David Carlier <devnexen@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
tcp_bpf_sendmsg() keeps msg_tx across sk_stream_wait_memory(), which
drops and reacquires the socket lock. Its error path tries to decide
whether msg_tx names the local temporary message by comparing it with
the current value of psock->cork.
This comparison is unsafe when two threads send on the same socket:
Thread A Thread B
msg_tx = psock->cork
sk_msg_alloc() fails
sk_stream_wait_memory()
releases the socket lock acquires the socket lock
completes the cork
psock->cork = NULL
frees the cork
reacquires the socket lock
msg_tx != psock->cork
sk_msg_free(msg_tx)
The stale cork is therefore mistaken for the local temporary message
and freed again. KASAN reported:
BUG: KASAN: slab-use-after-free in sk_msg_free+0x49/0x50
Read of size 4 at addr ffff88810c908800 by task poc/90
Call Trace:
sk_msg_free+0x49/0x50
tcp_bpf_sendmsg+0x14f5/0x1cc0
__sys_sendto+0x32c/0x3a0
__x64_sys_sendto+0xdb/0x1b0
Allocated by task 89:
__kasan_kmalloc+0x8f/0xa0
tcp_bpf_sendmsg+0x16b3/0x1cc0
Freed by task 91:
__kasan_slab_free+0x43/0x70
kfree+0x131/0x3c0
tcp_bpf_sendmsg+0xec3/0x1cc0
msg_tx can only name the stack-local tmp or the shared cork. Check for
tmp directly so a changed psock->cork cannot turn a shared message into
an apparent local one.
Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/87fr18lmzo.fsf%40cloudflare.com/
Link: https://lore.kernel.org/netdev/20260719161630.2901208-1-nicoyip.dev%40gmail.com/ [v1]
Link: https://patch.msgid.link/20260724103856.3399001-1-nicoyip.dev@gmail.com
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Pull drm fixes from Dave Airlie:
"Weekly drm pull request, small and scattered seems to be the new
normal, the ttm change is probably the largest, with xe being the
most. Alex was out this week so amdgpu is smaller and only has some
urgent fixes.
MAINTAINERS:
- update mailmap address
ttm:
- backup pages using correct order
gpusvm:
- fix mm leak on eviction
- properly zero page array in mm scanning
tests:
- fix dma mask errors in tests
panel:
- fix dependency issues
- ilitek-ili9881c - fix probing
i915:
- Remove DP_EDP_BACKLIGHT_AUX_ENABLE_CAP check for DPCD backlight
xe:
- Skip invalidation for purgeable state updates
- Add drm_dev guards when detaching CCS read / write buffers
- Alloc per domain unique i2c id
- Fix SVM leak on resv obj alloc failure in xe_vm_create
amdgpu:
- Fix a backport mistake for dm_gpureset_toggle_interrupts()
- Fix a failure on flip-done timeouts for mode1 reset
appletbdrm:
- fix issue in damage handling
amdxdna:
- fix command timeout race
imagination:
- fix gpu vm locking
vc4:
- prevent trusted bo from being mapped again
- prevent timer rearm on shutdown
v3d:
- fix NULL deref in unbind
- idle AXI before clock disable on suspend
- use proper GMP access for newer hw
vmwgfx:
- validate shader array size
ethosu:
- fix length calculations
- handle internal chaining buffers
gma500:
- return errors from HDMI i2c reads"
* tag 'drm-fixes-2026-07-25' of https://gitlab.freedesktop.org/drm/kernel: (31 commits)
drm/amd/display: Fix missing DCE check in dm_gpureset_toggle_interrupts()
drm/amd/display: Fix flip-done timeouts on mode1 reset
Revert "drm/pagemap: Guard HPAGE_PMD_ORDER use with CONFIG_ARCH_ENABLE_THP_MIGRATION"
drm/vc4: Shut down BO cache timer before teardown
drm/tests: shmem: Set DMA mask to 64-bit in drm_gem_shmem
drm/xe/vm: Fix SVM leak on resv obj alloc failure in xe_vm_create()
drm/xe/i2c: Allow per domain unique id
drm/gma500: return errors from Oaktrail HDMI I2C reads
drm/vc4: hvs/v3d: Fix null dereference in unbind
drm/panel: fix unmet dependency bug for DRM_PANEL_HIMAX_HX83121A
drm/panel: s6e3ha8: fix unmet dependency on DRM_DISPLAY_HELPER
drm/panel: ilitek-ili9882t: fix unmet dependency for DRM_PANEL_ILITEK_ILI9882T
drm/panel: ilitek-ili9881c: do not fail probe if iovcc is absent
drm/v3d: Idle AXI transactions before disabling the clock on suspend
drm/v3d: Reach the GMP through the hub registers on V3D 7.x
mailmap: Update Maíra Canal's email address
drm/pagemap: Guard HPAGE_PMD_ORDER use with CONFIG_ARCH_ENABLE_THP_MIGRATION
drm/pagemap: Clear driver-provided PFNs from migration PFN array
drm/xe/vf: Add drm_dev guards when detaching CCS read/write buffers
accel: ethosu: Handle U85 internal chaining buffer
...
