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

[ 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: Dan 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: Song Liu <song@kernel.org>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240125082131.788600-1-song@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Song Liu 2024-01-25 00:21:31 -08:00 committed by Greg Kroah-Hartman
parent be7f399e3f
commit b073267479

View File

@ -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>
@ -6519,7 +6520,18 @@ 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);