aboutsummaryrefslogtreecommitdiffstats
path: root/fs
diff options
context:
space:
mode:
authorWengang Wang <wen.gang.wang@oracle.com>2010-07-16 23:13:33 +0800
committerJoel Becker <joel.becker@oracle.com>2010-08-07 10:44:20 -0700
commit6d98c3ccb52f692f1a60339dde7c700686a5568b (patch)
treec43eabf9914d413d49d0bb650314295ac9e613c2 /fs
parent6eda3dd33f8a0ce58ee56a11351758643a698db4 (diff)
downloadmrst-s0i3-test-6d98c3ccb52f692f1a60339dde7c700686a5568b.tar.gz
mrst-s0i3-test-6d98c3ccb52f692f1a60339dde7c700686a5568b.tar.xz
mrst-s0i3-test-6d98c3ccb52f692f1a60339dde7c700686a5568b.zip
ocfs2/dlm: fix a dead lock
When we have to take both dlm->master_lock and lockres->spinlock, take them in order lockres->spinlock and then dlm->master_lock. The patch fixes a violation of the rule. We can simply move taking dlm->master_lock to where we have dropped res->spinlock since when we access res->state and free mle memory we don't need master_lock's protection. Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com> Cc: stable@kernel.org Signed-off-by: Joel Becker <joel.becker@oracle.com>
Diffstat (limited to 'fs')
-rw-r--r--fs/ocfs2/dlm/dlmmaster.c5
1 files changed, 2 insertions, 3 deletions
diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
index 94b97fc6a88..6d098b89d46 100644
--- a/fs/ocfs2/dlm/dlmmaster.c
+++ b/fs/ocfs2/dlm/dlmmaster.c
@@ -3050,8 +3050,6 @@ int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
/* check for pre-existing lock */
spin_lock(&dlm->spinlock);
res = __dlm_lookup_lockres(dlm, name, namelen, hash);
- spin_lock(&dlm->master_lock);
-
if (res) {
spin_lock(&res->spinlock);
if (res->state & DLM_LOCK_RES_RECOVERING) {
@@ -3069,14 +3067,15 @@ int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
spin_unlock(&res->spinlock);
}
+ spin_lock(&dlm->master_lock);
/* ignore status. only nonzero status would BUG. */
ret = dlm_add_migration_mle(dlm, res, mle, &oldmle,
name, namelen,
migrate->new_master,
migrate->master);
-unlock:
spin_unlock(&dlm->master_lock);
+unlock:
spin_unlock(&dlm->spinlock);
if (oldmle) {