Re: [PATCH -next] md:ensure mddev->reconfig_mutex is hold when try to get mddev->sync_thread
From: Li Lingfeng
Date: Thu Aug 03 2023 - 02:49:30 EST
Thanks for your advice, I will send a new patch soon.
在 2023/7/28 15:21, Paul Menzel 写道:
Dear Li,
Thank you for your patch.
I notice two minor things in the summary:
1. Please add a space after the colon
2. “is hold” should be “is held”.
Maybe even shorter:
md: Hold mddev->reconfig_mutex when trying to get mddev->sync_thread
Am 27.07.23 um 09:20 schrieb Li Lingfeng:
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.
Maybe also mention, that this is done by passing `mdev` to
`md_unregister_thread()`.
Plesae add a Fixes: tag.
This is not a bugfix patch , so I don't think it's necessary to add a
fix tag.
Signed-off-by: Li Lingfeng <lilingfeng@xxxxxxxxxxxxxxx>
---
drivers/md/md-cluster.c | 8 ++++----
drivers/md/md.c | 9 +++++----
drivers/md/md.h | 2 +-
drivers/md/raid1.c | 4 ++--
drivers/md/raid10.c | 2 +-
drivers/md/raid5-cache.c | 2 +-
drivers/md/raid5.c | 2 +-
7 files changed, 15 insertions(+), 14 deletions(-)
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 3d9fd74233df..1e26eb223349 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -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);
diff --git a/drivers/md/md.c b/drivers/md/md.c
index a3d98273b295..5c3c19b8d509 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -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) &&
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 8ae957480976..9bcb77bca963 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -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);
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 23d211969565..581dfbdfca89 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -3152,7 +3152,7 @@ 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;
}
@@ -3179,7 +3179,7 @@ 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;
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 16aa9d735880..6188b71186f4 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -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:
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index 47ba7d9e81e1..ce9b42fd54b9 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -3171,7 +3171,7 @@ void r5l_exit_log(struct r5conf *conf)
/* Ensure disable_writeback_work wakes up and exits */
wake_up(&conf->mddev->sb_wait);
flush_work(&log->disable_writeback_work);
- md_unregister_thread(&log->reclaim_thread);
+ md_unregister_thread(conf->mddev, &log->reclaim_thread);
conf->log = NULL;
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 4cdb35e54251..f41f9b712d3d 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -8107,7 +8107,7 @@ static int raid5_run(struct mddev *mddev)
return 0;
abort:
- md_unregister_thread(&mddev->thread);
+ md_unregister_thread(mddev, &mddev->thread);
print_raid5_conf(conf);
free_conf(conf);
mddev->private = NULL;