MD: fix sleep in atomic

bioset_free() will take a mutex, so can't get called with spinlock hold.

Fix: 5a85071c2cbc(md: use a separate bio_set for synchronous IO.)
Cc: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 092b48f8095e828cb387f805ea98150a32c5b674..66f6b928a80bc3025302b64cd9e1bd0f9a872b28 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -475,6 +475,8 @@ static void mddev_delayed_delete(struct work_struct *ws);
 
 static void mddev_put(struct mddev *mddev)
 {
+       struct bio_set *bs = NULL, *sync_bs = NULL;
+
        if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
                return;
        if (!mddev->raid_disks && list_empty(&mddev->disks) &&
@@ -482,10 +484,8 @@ static void mddev_put(struct mddev *mddev)
                /* Array is not configured at all, and not held active,
                 * so destroy it */
                list_del_init(&mddev->all_mddevs);
-               if (mddev->bio_set)
-                       bioset_free(mddev->bio_set);
-               if (mddev->sync_set)
-                       bioset_free(mddev->sync_set);
+               bs = mddev->bio_set;
+               sync_bs = mddev->sync_set;
                mddev->bio_set = NULL;
                mddev->sync_set = NULL;
                if (mddev->gendisk) {
@@ -500,6 +500,10 @@ static void mddev_put(struct mddev *mddev)
                        kfree(mddev);
        }
        spin_unlock(&all_mddevs_lock);
+       if (bs)
+               bioset_free(bs);
+       if (sync_bs)
+               bioset_free(sync_bs);
 }
 
 static void md_safemode_timeout(unsigned long data);