md-cluster: protect md_find_rdev_nr_rcu with rcu lock

We need to use rcu_read_lock/unlock to avoid potential
race.

Reported-by: Shaohua Li <shli@fb.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This commit is contained in:
Guoqing Jiang 2016-08-12 13:42:39 +08:00 committed by Shaohua Li
parent c20c33f0e2
commit 5f0aa21da6

View File

@ -489,9 +489,10 @@ static void process_metadata_update(struct mddev *mddev, struct cluster_msg *msg
static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
{
struct md_rdev *rdev = md_find_rdev_nr_rcu(mddev,
le32_to_cpu(msg->raid_slot));
struct md_rdev *rdev;
rcu_read_lock();
rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
if (rdev) {
set_bit(ClusterRemove, &rdev->flags);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
@ -500,18 +501,21 @@ static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
else
pr_warn("%s: %d Could not find disk(%d) to REMOVE\n",
__func__, __LINE__, le32_to_cpu(msg->raid_slot));
rcu_read_unlock();
}
static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg)
{
struct md_rdev *rdev = md_find_rdev_nr_rcu(mddev,
le32_to_cpu(msg->raid_slot));
struct md_rdev *rdev;
rcu_read_lock();
rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
if (rdev && test_bit(Faulty, &rdev->flags))
clear_bit(Faulty, &rdev->flags);
else
pr_warn("%s: %d Could not find disk(%d) which is faulty",
__func__, __LINE__, le32_to_cpu(msg->raid_slot));
rcu_read_unlock();
}
static int process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)