<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/md, branch v4.19.296</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>md/raid1: fix error: ISO C90 forbids mixed declarations</title>
<updated>2023-09-23T08:48:17+00:00</updated>
<author>
<name>Nigel Croxon</name>
<email>ncroxon@redhat.com</email>
</author>
<published>2023-09-11T21:25:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d9096f58481898f14481008251c86d1df1b780a7'/>
<id>d9096f58481898f14481008251c86d1df1b780a7</id>
<content type='text'>
[ Upstream commit df203da47f4428bc286fc99318936416253a321c ]

There is a compile error when this commit is added:
md: raid1: fix potential OOB in raid1_remove_disk()

drivers/md/raid1.c: In function 'raid1_remove_disk':
drivers/md/raid1.c:1844:9: error: ISO C90 forbids mixed declarations
and code [-Werror=declaration-after-statement]
1844 |         struct raid1_info *p = conf-&gt;mirrors + number;
     |         ^~~~~~

That's because the new code was inserted before the struct.
The change is move the struct command above this commit.

Fixes: 8b0472b50bcf ("md: raid1: fix potential OOB in raid1_remove_disk()")
Signed-off-by: Nigel Croxon &lt;ncroxon@redhat.com&gt;
Signed-off-by: Song Liu &lt;song@kernel.org&gt;
Link: https://lore.kernel.org/r/46d929d0-2aab-4cf2-b2bf-338963e8ba5a@redhat.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit df203da47f4428bc286fc99318936416253a321c ]

There is a compile error when this commit is added:
md: raid1: fix potential OOB in raid1_remove_disk()

drivers/md/raid1.c: In function 'raid1_remove_disk':
drivers/md/raid1.c:1844:9: error: ISO C90 forbids mixed declarations
and code [-Werror=declaration-after-statement]
1844 |         struct raid1_info *p = conf-&gt;mirrors + number;
     |         ^~~~~~

That's because the new code was inserted before the struct.
The change is move the struct command above this commit.

Fixes: 8b0472b50bcf ("md: raid1: fix potential OOB in raid1_remove_disk()")
Signed-off-by: Nigel Croxon &lt;ncroxon@redhat.com&gt;
Signed-off-by: Song Liu &lt;song@kernel.org&gt;
Link: https://lore.kernel.org/r/46d929d0-2aab-4cf2-b2bf-338963e8ba5a@redhat.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>md: raid1: fix potential OOB in raid1_remove_disk()</title>
<updated>2023-09-23T08:48:16+00:00</updated>
<author>
<name>Zhang Shurong</name>
<email>zhang_shurong@foxmail.com</email>
</author>
<published>2023-07-22T07:53:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=91fbd4e75cb573f44d2619a9dc2f9ba927040760'/>
<id>91fbd4e75cb573f44d2619a9dc2f9ba927040760</id>
<content type='text'>
[ Upstream commit 8b0472b50bcf0f19a5119b00a53b63579c8e1e4d ]

If rddev-&gt;raid_disk is greater than mddev-&gt;raid_disks, there will be
an out-of-bounds in raid1_remove_disk(). We have already found
similar reports as follows:

1) commit d17f744e883b ("md-raid10: fix KASAN warning")
2) commit 1ebc2cec0b7d ("dm raid: fix KASAN warning in raid5_remove_disk")

Fix this bug by checking whether the "number" variable is
valid.

Signed-off-by: Zhang Shurong &lt;zhang_shurong@foxmail.com&gt;
Reviewed-by: Yu Kuai &lt;yukuai3@huawei.com&gt;
Link: https://lore.kernel.org/r/tencent_0D24426FAC6A21B69AC0C03CE4143A508F09@qq.com
Signed-off-by: Song Liu &lt;song@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 8b0472b50bcf0f19a5119b00a53b63579c8e1e4d ]

If rddev-&gt;raid_disk is greater than mddev-&gt;raid_disks, there will be
an out-of-bounds in raid1_remove_disk(). We have already found
similar reports as follows:

1) commit d17f744e883b ("md-raid10: fix KASAN warning")
2) commit 1ebc2cec0b7d ("dm raid: fix KASAN warning in raid5_remove_disk")

Fix this bug by checking whether the "number" variable is
valid.

Signed-off-by: Zhang Shurong &lt;zhang_shurong@foxmail.com&gt;
Reviewed-by: Yu Kuai &lt;yukuai3@huawei.com&gt;
Link: https://lore.kernel.org/r/tencent_0D24426FAC6A21B69AC0C03CE4143A508F09@qq.com
Signed-off-by: Song Liu &lt;song@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>dm integrity: reduce vmalloc space footprint on 32-bit architectures</title>
<updated>2023-08-30T14:31:53+00:00</updated>
<author>
<name>Mikulas Patocka</name>
<email>mpatocka@redhat.com</email>
</author>
<published>2023-06-26T14:44:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=52f186f7db6af3ef51a8890fa05f96bfee7f5e41'/>
<id>52f186f7db6af3ef51a8890fa05f96bfee7f5e41</id>
<content type='text'>
[ Upstream commit 6d50eb4725934fd22f5eeccb401000687c790fd0 ]

It was reported that dm-integrity runs out of vmalloc space on 32-bit
architectures. On x86, there is only 128MiB vmalloc space and dm-integrity
consumes it quickly because it has a 64MiB journal and 8MiB recalculate
buffer.

Fix this by reducing the size of the journal to 4MiB and the size of
the recalculate buffer to 1MiB, so that multiple dm-integrity devices
can be created and activated on 32-bit architectures.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 6d50eb4725934fd22f5eeccb401000687c790fd0 ]

It was reported that dm-integrity runs out of vmalloc space on 32-bit
architectures. On x86, there is only 128MiB vmalloc space and dm-integrity
consumes it quickly because it has a 64MiB journal and 8MiB recalculate
buffer.

Fix this by reducing the size of the journal to 4MiB and the size of
the recalculate buffer to 1MiB, so that multiple dm-integrity devices
can be created and activated on 32-bit architectures.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>dm integrity: increase RECALC_SECTORS to improve recalculate speed</title>
<updated>2023-08-30T14:31:53+00:00</updated>
<author>
<name>Mikulas Patocka</name>
<email>mpatocka@redhat.com</email>
</author>
<published>2021-04-27T15:57:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=15569a09399ad24663310706da6f2208c34004ed'/>
<id>15569a09399ad24663310706da6f2208c34004ed</id>
<content type='text'>
[ Upstream commit b1a2b9332050c7ae32a22c2c74bc443e39f37b23 ]

Increase RECALC_SECTORS because it improves recalculate speed slightly
(from 390kiB/s to 410kiB/s).

Signed-off-by: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
Stable-dep-of: 6d50eb472593 ("dm integrity: reduce vmalloc space footprint on 32-bit architectures")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b1a2b9332050c7ae32a22c2c74bc443e39f37b23 ]

Increase RECALC_SECTORS because it improves recalculate speed slightly
(from 390kiB/s to 410kiB/s).

Signed-off-by: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@redhat.com&gt;
Stable-dep-of: 6d50eb472593 ("dm integrity: reduce vmalloc space footprint on 32-bit architectures")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>dm cache policy smq: ensure IO doesn't prevent cleaner policy progress</title>
<updated>2023-08-11T09:45:35+00:00</updated>
<author>
<name>Joe Thornber</name>
<email>ejt@redhat.com</email>
</author>
<published>2023-07-25T15:44:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=aecee8669ad3ba9adecc19c20c2f47509b81c70a'/>
<id>aecee8669ad3ba9adecc19c20c2f47509b81c70a</id>
<content type='text'>
commit 1e4ab7b4c881cf26c1c72b3f56519e03475486fb upstream.

When using the cleaner policy to decommission the cache, there is
never any writeback started from the cache as it is constantly delayed
due to normal I/O keeping the device busy. Meaning @idle=false was
always being passed to clean_target_met()

Fix this by adding a specific 'cleaner' flag that is set when the
cleaner policy is configured. This flag serves to always allow the
cleaner's writeback work to be queued until the cache is
decommissioned (even if the cache isn't idle).

Reported-by: David Jeffery &lt;djeffery@redhat.com&gt;
Fixes: b29d4986d0da ("dm cache: significant rework to leverage dm-bio-prison-v2")
Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber &lt;ejt@redhat.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 1e4ab7b4c881cf26c1c72b3f56519e03475486fb upstream.

When using the cleaner policy to decommission the cache, there is
never any writeback started from the cache as it is constantly delayed
due to normal I/O keeping the device busy. Meaning @idle=false was
always being passed to clean_target_met()

Fix this by adding a specific 'cleaner' flag that is set when the
cleaner policy is configured. This flag serves to always allow the
cleaner's writeback work to be queued until the cache is
decommissioned (even if the cache isn't idle).

Reported-by: David Jeffery &lt;djeffery@redhat.com&gt;
Fixes: b29d4986d0da ("dm cache: significant rework to leverage dm-bio-prison-v2")
Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber &lt;ejt@redhat.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>dm raid: fix missing reconfig_mutex unlock in raid_ctr() error paths</title>
<updated>2023-08-11T09:45:32+00:00</updated>
<author>
<name>Yu Kuai</name>
<email>yukuai3@huawei.com</email>
</author>
<published>2023-07-08T09:21:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2e687f8b5f4348a588cd5f456539eb27fcc2ebf1'/>
<id>2e687f8b5f4348a588cd5f456539eb27fcc2ebf1</id>
<content type='text'>
[ Upstream commit bae3028799dc4f1109acc4df37c8ff06f2d8f1a0 ]

In the error paths 'bad_stripe_cache' and 'bad_check_reshape',
'reconfig_mutex' is still held after raid_ctr() returns.

Fixes: 9dbd1aa3a81c ("dm raid: add reshaping support to the target")
Signed-off-by: Yu Kuai &lt;yukuai3@huawei.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit bae3028799dc4f1109acc4df37c8ff06f2d8f1a0 ]

In the error paths 'bad_stripe_cache' and 'bad_check_reshape',
'reconfig_mutex' is still held after raid_ctr() returns.

Fixes: 9dbd1aa3a81c ("dm raid: add reshaping support to the target")
Signed-off-by: Yu Kuai &lt;yukuai3@huawei.com&gt;
Signed-off-by: Mike Snitzer &lt;snitzer@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent</title>
<updated>2023-08-11T09:45:28+00:00</updated>
<author>
<name>Zheng Wang</name>
<email>zyytlz.wz@163.com</email>
</author>
<published>2023-06-15T12:12:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=587b4e8bb5dac682f09280ab35db4632b29d5ac4'/>
<id>587b4e8bb5dac682f09280ab35db4632b29d5ac4</id>
<content type='text'>
[ Upstream commit 80fca8a10b604afad6c14213fdfd816c4eda3ee4 ]

In some specific situations, the return value of __bch_btree_node_alloc
may be NULL. This may lead to a potential NULL pointer dereference in
caller function like a calling chain :
btree_split-&gt;bch_btree_node_alloc-&gt;__bch_btree_node_alloc.

Fix it by initializing the return value in __bch_btree_node_alloc.

Fixes: cafe56359144 ("bcache: A block layer cache")
Cc: stable@vger.kernel.org
Signed-off-by: Zheng Wang &lt;zyytlz.wz@163.com&gt;
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Link: https://lore.kernel.org/r/20230615121223.22502-6-colyli@suse.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 80fca8a10b604afad6c14213fdfd816c4eda3ee4 ]

In some specific situations, the return value of __bch_btree_node_alloc
may be NULL. This may lead to a potential NULL pointer dereference in
caller function like a calling chain :
btree_split-&gt;bch_btree_node_alloc-&gt;__bch_btree_node_alloc.

Fix it by initializing the return value in __bch_btree_node_alloc.

Fixes: cafe56359144 ("bcache: A block layer cache")
Cc: stable@vger.kernel.org
Signed-off-by: Zheng Wang &lt;zyytlz.wz@163.com&gt;
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Link: https://lore.kernel.org/r/20230615121223.22502-6-colyli@suse.de
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bcache: remove 'int n' from parameter list of bch_bucket_alloc_set()</title>
<updated>2023-08-11T09:45:28+00:00</updated>
<author>
<name>Coly Li</name>
<email>colyli@suse.de</email>
</author>
<published>2020-10-01T06:50:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=05ddb85c2bf21b3682f863688d2a3db27d9e6935'/>
<id>05ddb85c2bf21b3682f863688d2a3db27d9e6935</id>
<content type='text'>
[ Upstream commit 17e4aed8309ff28670271546c2c3263eb12f5eb6 ]

The parameter 'int n' from bch_bucket_alloc_set() is not cleared
defined. From the code comments n is the number of buckets to alloc, but
from the code itself 'n' is the maximum cache to iterate. Indeed all the
locations where bch_bucket_alloc_set() is called, 'n' is alwasy 1.

This patch removes the confused and unnecessary 'int n' from parameter
list of  bch_bucket_alloc_set(), and explicitly allocates only 1 bucket
for its caller.

Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Stable-dep-of: 80fca8a10b60 ("bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 17e4aed8309ff28670271546c2c3263eb12f5eb6 ]

The parameter 'int n' from bch_bucket_alloc_set() is not cleared
defined. From the code comments n is the number of buckets to alloc, but
from the code itself 'n' is the maximum cache to iterate. Indeed all the
locations where bch_bucket_alloc_set() is called, 'n' is alwasy 1.

This patch removes the confused and unnecessary 'int n' from parameter
list of  bch_bucket_alloc_set(), and explicitly allocates only 1 bucket
for its caller.

Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Stable-dep-of: 80fca8a10b60 ("bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bcache: use MAX_CACHES_PER_SET instead of magic number 8 in __bch_bucket_alloc_set</title>
<updated>2023-08-11T09:45:28+00:00</updated>
<author>
<name>Shenghui Wang</name>
<email>shhuiw@foxmail.com</email>
</author>
<published>2018-10-08T12:41:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=49041888d8c7d5476efa88266063a6b9104e4694'/>
<id>49041888d8c7d5476efa88266063a6b9104e4694</id>
<content type='text'>
[ Upstream commit 8792099f9ad487cf381f4e8199ff2158ba0f6eb5 ]

Current cache_set has MAX_CACHES_PER_SET caches most, and the macro
is used for
"
	struct cache *cache_by_alloc[MAX_CACHES_PER_SET];
"
in the define of struct cache_set.

Use MAX_CACHES_PER_SET instead of magic number 8 in
__bch_bucket_alloc_set.

Signed-off-by: Shenghui Wang &lt;shhuiw@foxmail.com&gt;
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Stable-dep-of: 80fca8a10b60 ("bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 8792099f9ad487cf381f4e8199ff2158ba0f6eb5 ]

Current cache_set has MAX_CACHES_PER_SET caches most, and the macro
is used for
"
	struct cache *cache_by_alloc[MAX_CACHES_PER_SET];
"
in the define of struct cache_set.

Use MAX_CACHES_PER_SET instead of magic number 8 in
__bch_bucket_alloc_set.

Signed-off-by: Shenghui Wang &lt;shhuiw@foxmail.com&gt;
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Stable-dep-of: 80fca8a10b60 ("bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>md/raid10: prevent soft lockup while flush writes</title>
<updated>2023-08-11T09:45:25+00:00</updated>
<author>
<name>Yu Kuai</name>
<email>yukuai3@huawei.com</email>
</author>
<published>2023-05-29T13:11:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=00ecb6fa67c0f772290c5ea5ae8b46eefd503b83'/>
<id>00ecb6fa67c0f772290c5ea5ae8b46eefd503b83</id>
<content type='text'>
[ Upstream commit 010444623e7f4da6b4a4dd603a7da7469981e293 ]

Currently, there is no limit for raid1/raid10 plugged bio. While flushing
writes, raid1 has cond_resched() while raid10 doesn't, and too many
writes can cause soft lockup.

Follow up soft lockup can be triggered easily with writeback test for
raid10 with ramdisks:

watchdog: BUG: soft lockup - CPU#10 stuck for 27s! [md0_raid10:1293]
Call Trace:
 &lt;TASK&gt;
 call_rcu+0x16/0x20
 put_object+0x41/0x80
 __delete_object+0x50/0x90
 delete_object_full+0x2b/0x40
 kmemleak_free+0x46/0xa0
 slab_free_freelist_hook.constprop.0+0xed/0x1a0
 kmem_cache_free+0xfd/0x300
 mempool_free_slab+0x1f/0x30
 mempool_free+0x3a/0x100
 bio_free+0x59/0x80
 bio_put+0xcf/0x2c0
 free_r10bio+0xbf/0xf0
 raid_end_bio_io+0x78/0xb0
 one_write_done+0x8a/0xa0
 raid10_end_write_request+0x1b4/0x430
 bio_endio+0x175/0x320
 brd_submit_bio+0x3b9/0x9b7 [brd]
 __submit_bio+0x69/0xe0
 submit_bio_noacct_nocheck+0x1e6/0x5a0
 submit_bio_noacct+0x38c/0x7e0
 flush_pending_writes+0xf0/0x240
 raid10d+0xac/0x1ed0

Fix the problem by adding cond_resched() to raid10 like what raid1 did.

Note that unlimited plugged bio still need to be optimized, for example,
in the case of lots of dirty pages writeback, this will take lots of
memory and io will spend a long time in plug, hence io latency is bad.

Signed-off-by: Yu Kuai &lt;yukuai3@huawei.com&gt;
Signed-off-by: Song Liu &lt;song@kernel.org&gt;
Link: https://lore.kernel.org/r/20230529131106.2123367-2-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
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[ Upstream commit 010444623e7f4da6b4a4dd603a7da7469981e293 ]

Currently, there is no limit for raid1/raid10 plugged bio. While flushing
writes, raid1 has cond_resched() while raid10 doesn't, and too many
writes can cause soft lockup.

Follow up soft lockup can be triggered easily with writeback test for
raid10 with ramdisks:

watchdog: BUG: soft lockup - CPU#10 stuck for 27s! [md0_raid10:1293]
Call Trace:
 &lt;TASK&gt;
 call_rcu+0x16/0x20
 put_object+0x41/0x80
 __delete_object+0x50/0x90
 delete_object_full+0x2b/0x40
 kmemleak_free+0x46/0xa0
 slab_free_freelist_hook.constprop.0+0xed/0x1a0
 kmem_cache_free+0xfd/0x300
 mempool_free_slab+0x1f/0x30
 mempool_free+0x3a/0x100
 bio_free+0x59/0x80
 bio_put+0xcf/0x2c0
 free_r10bio+0xbf/0xf0
 raid_end_bio_io+0x78/0xb0
 one_write_done+0x8a/0xa0
 raid10_end_write_request+0x1b4/0x430
 bio_endio+0x175/0x320
 brd_submit_bio+0x3b9/0x9b7 [brd]
 __submit_bio+0x69/0xe0
 submit_bio_noacct_nocheck+0x1e6/0x5a0
 submit_bio_noacct+0x38c/0x7e0
 flush_pending_writes+0xf0/0x240
 raid10d+0xac/0x1ed0

Fix the problem by adding cond_resched() to raid10 like what raid1 did.

Note that unlimited plugged bio still need to be optimized, for example,
in the case of lots of dirty pages writeback, this will take lots of
memory and io will spend a long time in plug, hence io latency is bad.

Signed-off-by: Yu Kuai &lt;yukuai3@huawei.com&gt;
Signed-off-by: Song Liu &lt;song@kernel.org&gt;
Link: https://lore.kernel.org/r/20230529131106.2123367-2-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
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