Commit 1e8a1349 authored by Song Liu's avatar Song Liu Committed by Li Nan
Browse files

Revert "Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"" 

stable inclusion
from stable-v5.10.215
commit b07326747952c6f109e4aa92801abac99e1a27fe
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAB04V
CVE: CVE-2024-39476

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b07326747952c6f109e4aa92801abac99e1a27fe



--------------------------------

[ Upstream commit 3445139e3a594be77eff48bc17eff67cf983daed ]

This reverts commit bed9e27baf52a09b7ba2a3714f1e24e17ced386d.

The original set [1][2] was expected to undo a suboptimal fix in [2], and
replace it with a better fix [1]. However, as reported by Dan Moulding [2]
causes an issue with raid5 with journal device.

Revert [2] for now to close the issue. We will follow up on another issue
reported by Juxiao Bi, as [2] is expected to fix it. We believe this is a
good trade-off, because the latter issue happens less freqently.

In the meanwhile, we will NOT revert [1], as it contains the right logic.

[1] commit d6e035aad6c0 ("md: bypass block throttle for superblock update")
[2] commit bed9e27baf52 ("Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"")

Reported-by: default avatarDan Moulding <dan@danm.net>
Closes: https://lore.kernel.org/linux-raid/20240123005700.9302-1-dan@danm.net/


Fixes: bed9e27baf52 ("Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"")
Cc: stable@vger.kernel.org # v5.19+
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: default avatarSong Liu <song@kernel.org>
Reviewed-by: default avatarYu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240125082131.788600-1-song@kernel.org


Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarWang Hai <wanghai38@huawei.com>
Signed-off-by: default avatarLi Nan <linan122@huawei.com>
parent 563a37de

drivers/md/raid5.c

+12 −0
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ 
 */



#include <linux/blkdev.h>

#include <linux/delay.h>

#include <linux/kthread.h>

#include <linux/raid/pq.h>

#include <linux/async_tx.h>
@@ -6511,7 +6512,18 @@ static void raid5d(struct md_thread *thread) 
			spin_unlock_irq(&conf->device_lock);

			md_check_recovery(mddev);

			spin_lock_irq(&conf->device_lock);



			/*

			 * Waiting on MD_SB_CHANGE_PENDING below may deadlock

			 * seeing md_check_recovery() is needed to clear

			 * the flag when using mdmon.

			 */

			continue;

		}



		wait_event_lock_irq(mddev->sb_wait,

			!test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags),

			conf->device_lock);

	}

	pr_debug("%d stripes handled\n", handled);