From 9dfbdafda3b34e262e43e786077bab8e476a89d1 Mon Sep 17 00:00:00 2001 From: Guoqing Jiang Date: Tue, 21 Jun 2022 11:11:29 +0800 Subject: [PATCH] md: unlock mddev before reap sync_thread in action_store Since the bug which commit 8b48ec23cc51a ("md: don't unregister sync_thread with reconfig_mutex held") fixed is related with action_store path, other callers which reap sync_thread didn't need to be changed. Let's pull md_unregister_thread from md_reap_sync_thread, then fix previous bug with belows. 1. unlock mddev before md_reap_sync_thread in action_store. 2. save reshape_position before unlock, then restore it to ensure position not changed accidentally by others. Signed-off-by: Guoqing Jiang Signed-off-by: Song Liu Signed-off-by: Jens Axboe --- drivers/md/dm-raid.c | 1 + drivers/md/md.c | 19 +++++++++++++++++-- 2 files changed, 18 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index 1ec17c32867f..c640be453313 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -3728,6 +3728,7 @@ 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_unregister_thread(&mddev->sync_thread); md_reap_sync_thread(mddev); } } else if (decipher_sync_action(mddev, mddev->recovery) != st_idle) diff --git a/drivers/md/md.c b/drivers/md/md.c index f511f183aca6..7bc967131ac5 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -4830,6 +4830,19 @@ action_store(struct mddev *mddev, const char *page, size_t len) if (work_pending(&mddev->del_work)) flush_workqueue(md_misc_wq); if (mddev->sync_thread) { + sector_t save_rp = mddev->reshape_position; + + mddev_unlock(mddev); + set_bit(MD_RECOVERY_INTR, &mddev->recovery); + md_unregister_thread(&mddev->sync_thread); + mddev_lock_nointr(mddev); + /* + * set RECOVERY_INTR again and restore reshape + * position in case others changed them after + * got lock, eg, reshape_position_store and + * md_check_recovery. + */ + mddev->reshape_position = save_rp; set_bit(MD_RECOVERY_INTR, &mddev->recovery); md_reap_sync_thread(mddev); } @@ -6197,6 +6210,7 @@ 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_unregister_thread(&mddev->sync_thread); md_reap_sync_thread(mddev); } @@ -9309,6 +9323,7 @@ void md_check_recovery(struct mddev *mddev) * ->spare_active and clear saved_raid_disk */ set_bit(MD_RECOVERY_INTR, &mddev->recovery); + md_unregister_thread(&mddev->sync_thread); md_reap_sync_thread(mddev); clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery); clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery); @@ -9344,6 +9359,7 @@ void md_check_recovery(struct mddev *mddev) goto unlock; } if (mddev->sync_thread) { + md_unregister_thread(&mddev->sync_thread); md_reap_sync_thread(mddev); goto unlock; } @@ -9423,8 +9439,7 @@ void md_reap_sync_thread(struct mddev *mddev) sector_t old_dev_sectors = mddev->dev_sectors; bool is_reshaped = false; - /* resync has finished, collect result */ - md_unregister_thread(&mddev->sync_thread); + /* sync_thread should be unregistered, collect result */ if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery) && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && mddev->degraded != mddev->raid_disks) { -- 2.25.1