From aab69ef769707ad987ff905d79e0bd6591812580 Mon Sep 17 00:00:00 2001 From: Song Liu Date: Thu, 25 Jan 2024 00:21:31 -0800 Subject: [PATCH] Revert "Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"" 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 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 Cc: Yu Kuai Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman --- drivers/md/raid5.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 4bbd2a2..68d86db 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -36,6 +36,7 @@ */ #include +#include #include #include #include @@ -6842,7 +6843,18 @@ 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); -- 2.7.4