Commit 7eb8ff02 authored by Li Lingfeng's avatar Li Lingfeng Committed by Song Liu
Browse files

md: Hold mddev->reconfig_mutex when trying to get mddev->sync_thread 



Commit ba9d9f1a707f ("Revert "md: unlock mddev before reap sync_thread in
action_store"") removed the scenario of calling md_unregister_thread()
without holding mddev->reconfig_mutex, so add a lock holding check before
acquiring mddev->sync_thread by passing mdev to md_unregister_thread().

Signed-off-by: default avatarLi Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: default avatarYu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20230803071711.2546560-1-lilingfeng@huaweicloud.com


Signed-off-by: default avatarSong Liu <song@kernel.org>
parent 892da88d

drivers/md/md-cluster.c

+4 −4
Original line number Diff line number Diff line
@@ -952,8 +952,8 @@ static int join(struct mddev *mddev, int nodes) 
	return 0;

err:

	set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);

	md_unregister_thread(&cinfo->recovery_thread);

	md_unregister_thread(&cinfo->recv_thread);

	md_unregister_thread(mddev, &cinfo->recovery_thread);

	md_unregister_thread(mddev, &cinfo->recv_thread);

	lockres_free(cinfo->message_lockres);

	lockres_free(cinfo->token_lockres);

	lockres_free(cinfo->ack_lockres);
@@ -1015,8 +1015,8 @@ static int leave(struct mddev *mddev) 
		resync_bitmap(mddev);



	set_bit(MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD, &cinfo->state);

	md_unregister_thread(&cinfo->recovery_thread);

	md_unregister_thread(&cinfo->recv_thread);

	md_unregister_thread(mddev, &cinfo->recovery_thread);

	md_unregister_thread(mddev, &cinfo->recv_thread);

	lockres_free(cinfo->message_lockres);

	lockres_free(cinfo->token_lockres);

	lockres_free(cinfo->ack_lockres);

drivers/md/md.c

+5 −4
Original line number Diff line number Diff line
@@ -6258,7 +6258,7 @@ static void mddev_detach(struct mddev *mddev) 
		mddev->pers->quiesce(mddev, 1);

		mddev->pers->quiesce(mddev, 0);

	}

	md_unregister_thread(&mddev->thread);

	md_unregister_thread(mddev, &mddev->thread);

	if (mddev->queue)

		blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/

}
@@ -7990,9 +7990,10 @@ struct md_thread *md_register_thread(void (*run) (struct md_thread *), 
}

EXPORT_SYMBOL(md_register_thread);



void md_unregister_thread(struct md_thread __rcu **threadp)

void md_unregister_thread(struct mddev *mddev, struct md_thread __rcu **threadp)

{

	struct md_thread *thread = rcu_dereference_protected(*threadp, true);

	struct md_thread *thread = rcu_dereference_protected(*threadp,

					lockdep_is_held(&mddev->reconfig_mutex));



	if (!thread)

		return;
@@ -9484,7 +9485,7 @@ void md_reap_sync_thread(struct mddev *mddev) 
	bool is_reshaped = false;



	/* resync has finished, collect result */

	md_unregister_thread(&mddev->sync_thread);

	md_unregister_thread(mddev, &mddev->sync_thread);

	atomic_inc(&mddev->sync_seq);



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

drivers/md/md.h

+1 −1
Original line number Diff line number Diff line
@@ -761,7 +761,7 @@ extern struct md_thread *md_register_thread( 
	void (*run)(struct md_thread *thread),

	struct mddev *mddev,

	const char *name);

extern void md_unregister_thread(struct md_thread __rcu **threadp);

extern void md_unregister_thread(struct mddev *mddev, struct md_thread __rcu **threadp);

extern void md_wakeup_thread(struct md_thread __rcu *thread);

extern void md_check_recovery(struct mddev *mddev);

extern void md_reap_sync_thread(struct mddev *mddev);

drivers/md/raid1.c

+2 −2
Original line number Diff line number Diff line
@@ -3156,7 +3156,7 @@ static int raid1_run(struct mddev *mddev) 
	 * RAID1 needs at least one disk in active

	 */

	if (conf->raid_disks - mddev->degraded < 1) {

		md_unregister_thread(&conf->thread);

		md_unregister_thread(mddev, &conf->thread);

		ret = -EINVAL;

		goto abort;

	}
@@ -3183,7 +3183,7 @@ static int raid1_run(struct mddev *mddev) 


	ret = md_integrity_register(mddev);

	if (ret) {

		md_unregister_thread(&mddev->thread);

		md_unregister_thread(mddev, &mddev->thread);

		goto abort;

	}

	return 0;

drivers/md/raid10.c

+1 −1
Original line number Diff line number Diff line
@@ -4320,7 +4320,7 @@ static int raid10_run(struct mddev *mddev) 
	return 0;



out_free_conf:

	md_unregister_thread(&mddev->thread);

	md_unregister_thread(mddev, &mddev->thread);

	raid10_free_conf(conf);

	mddev->private = NULL;

out: