From: Yu Kuai <yukuai3@xxxxxxxxxx> stop_sync_thread() will interrupt md_do_sync(), and md_do_sync() must set MD_RECOVERY_DONE, so that follow up md_check_recovery() will unregister sync_thread, clear MD_RECOVERY_RUNNING and wake up stop_sync_thread(). If MD_RECOVERY_WAIT is set or the array is read-only, md_do_sync() will return without setting MD_RECOVERY_DONE, and after commit f52f5c71f3d4 ("md: fix stopping sync thread"), dm-raid switch from md_reap_sync_thread() to stop_sync_thread() to unregister sync_thread from md_stop() and md_stop_writes(), causing the test shell/lvconvert-raid-reshape.sh hang. We shouldn't switch back to md_reap_sync_thread() because it's problematic in the first place. Fix the problem by making sure md_do_sync() will set MD_RECOVERY_DONE. Reported-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> Closes: https://lore.kernel.org/all/ece2b06f-d647-6613-a534-ff4c9bec1142@xxxxxxxxxx/ Fixes: d5d885fd514f ("md: introduce new personality funciton start()") Fixes: 5fd6c1dce06e ("[PATCH] md: allow checkpoint of recovery with version-1 superblock") Fixes: f52f5c71f3d4 ("md: fix stopping sync thread") Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx> --- drivers/md/md.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 6906d023f1d6..c65dfd156090 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -8788,12 +8788,16 @@ void md_do_sync(struct md_thread *thread) int ret; /* just incase thread restarts... */ - if (test_bit(MD_RECOVERY_DONE, &mddev->recovery) || - test_bit(MD_RECOVERY_WAIT, &mddev->recovery)) + if (test_bit(MD_RECOVERY_DONE, &mddev->recovery)) return; - if (!md_is_rdwr(mddev)) {/* never try to sync a read-only array */ + + if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) + goto skip; + + if (test_bit(MD_RECOVERY_WAIT, &mddev->recovery) || + !md_is_rdwr(mddev)) {/* never try to sync a read-only array */ set_bit(MD_RECOVERY_INTR, &mddev->recovery); - return; + goto skip; } if (mddev_is_clustered(mddev)) { -- 2.39.2