From 9dfbdafda3b34e262e43e786077bab8e476a89d1 Mon Sep 17 00:00:00 2001
From: Guoqing Jiang <guoqing.jiang@linux.dev>
Date: Tue, 21 Jun 2022 11:11:29 +0800
Subject: [PATCH] md: unlock mddev before reap sync_thread in action_store
Git-commit: 9dfbdafda3b34e262e43e786077bab8e476a89d1
Patch-mainline: v6.0-rc1
References: bsc#1197659
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 <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Coly Li <colyli@suse.de>
---
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) {
--
2.35.3