Commit d0a18034 authored by Guoqing Jiang's avatar Guoqing Jiang Committed by Song Liu
Browse files

Revert "md: don't unregister sync_thread with reconfig_mutex held" 



The 07reshape5intr test is broke because of below path.

    md_reap_sync_thread
            -> mddev_unlock
            -> md_unregister_thread(&mddev->sync_thread)

And md_check_recovery is triggered by,

mddev_unlock -> md_wakeup_thread(mddev->thread)

then mddev->reshape_position is set to MaxSector in raid5_finish_reshape
since MD_RECOVERY_INTR is cleared in md_check_recovery, which means
feature_map is not set with MD_FEATURE_RESHAPE_ACTIVE and superblock's
reshape_position can't be updated accordingly.

Fixes: 8b48ec23 ("md: don't unregister sync_thread with reconfig_mutex held")
Reported-by: default avatarLogan Gunthorpe <logang@deltatee.com>
Signed-off-by: default avatarGuoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: default avatarSong Liu <song@kernel.org>
parent 2396e958

drivers/md/dm-raid.c

+1 −1
Original line number Diff line number Diff line
@@ -3725,7 +3725,7 @@ static int raid_message(struct dm_target *ti, unsigned int argc, char **argv, 
	if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {

		if (mddev->sync_thread) {

			set_bit(MD_RECOVERY_INTR, &mddev->recovery);

			md_reap_sync_thread(mddev, false);

			md_reap_sync_thread(mddev);

		}

	} else if (decipher_sync_action(mddev, mddev->recovery) != st_idle)

		return -EBUSY;

drivers/md/md.c

+5 −9
Original line number Diff line number Diff line
@@ -4831,7 +4831,7 @@ action_store(struct mddev *mddev, const char *page, size_t len) 
				flush_workqueue(md_misc_wq);

			if (mddev->sync_thread) {

				set_bit(MD_RECOVERY_INTR, &mddev->recovery);

				md_reap_sync_thread(mddev, true);

				md_reap_sync_thread(mddev);

			}

			mddev_unlock(mddev);

		}
@@ -6197,7 +6197,7 @@ static void __md_stop_writes(struct mddev *mddev) 
		flush_workqueue(md_misc_wq);

	if (mddev->sync_thread) {

		set_bit(MD_RECOVERY_INTR, &mddev->recovery);

		md_reap_sync_thread(mddev, true);

		md_reap_sync_thread(mddev);

	}



	del_timer_sync(&mddev->safemode_timer);
@@ -9303,7 +9303,7 @@ void md_check_recovery(struct mddev *mddev) 
			 * ->spare_active and clear saved_raid_disk

			 */

			set_bit(MD_RECOVERY_INTR, &mddev->recovery);

			md_reap_sync_thread(mddev, true);

			md_reap_sync_thread(mddev);

			clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);

			clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);

			clear_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags);
@@ -9338,7 +9338,7 @@ void md_check_recovery(struct mddev *mddev) 
			goto unlock;

		}

		if (mddev->sync_thread) {

			md_reap_sync_thread(mddev, true);

			md_reap_sync_thread(mddev);

			goto unlock;

		}

		/* Set RUNNING before clearing NEEDED to avoid
@@ -9411,18 +9411,14 @@ void md_check_recovery(struct mddev *mddev) 
}

EXPORT_SYMBOL(md_check_recovery);



void md_reap_sync_thread(struct mddev *mddev, bool reconfig_mutex_held)

void md_reap_sync_thread(struct mddev *mddev)

{

	struct md_rdev *rdev;

	sector_t old_dev_sectors = mddev->dev_sectors;

	bool is_reshaped = false;



	if (reconfig_mutex_held)

		mddev_unlock(mddev);

	/* resync has finished, collect result */

	md_unregister_thread(&mddev->sync_thread);

	if (reconfig_mutex_held)

		mddev_lock_nointr(mddev);

	if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) &&

	    !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&

	    mddev->degraded != mddev->raid_disks) {

drivers/md/md.h

+1 −1
Original line number Diff line number Diff line
@@ -719,7 +719,7 @@ extern struct md_thread *md_register_thread( 
extern void md_unregister_thread(struct md_thread **threadp);

extern void md_wakeup_thread(struct md_thread *thread);

extern void md_check_recovery(struct mddev *mddev);

extern void md_reap_sync_thread(struct mddev *mddev, bool reconfig_mutex_held);

extern void md_reap_sync_thread(struct mddev *mddev);

extern int mddev_init_writes_pending(struct mddev *mddev);

extern bool md_write_start(struct mddev *mddev, struct bio *bi);

extern void md_write_inc(struct mddev *mddev, struct bio *bi);