ocfs2/dlm: unlock lockres spinlock before dlm_lockres_put
authorJoseph Qi <joseph.qi@huawei.com>
Thu, 22 Oct 2015 20:32:29 +0000 (13:32 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 23 Oct 2015 08:55:10 +0000 (17:55 +0900)
dlm_lockres_put will call dlm_lockres_release if it is the last
reference, and then it may call dlm_print_one_lock_resource and
take lockres spinlock.

So unlock lockres spinlock before dlm_lockres_put to avoid deadlock.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/ocfs2/dlm/dlmmaster.c
fs/ocfs2/dlm/dlmrecovery.c

index ee5aa4d..ce38b4c 100644 (file)
@@ -1658,12 +1658,13 @@ send_response:
                if (ret < 0) {
                        mlog(ML_ERROR, "failed to dispatch assert master work\n");
                        response = DLM_MASTER_RESP_ERROR;
+                       spin_unlock(&res->spinlock);
                        dlm_lockres_put(res);
                } else {
                        dispatched = 1;
                        __dlm_lockres_grab_inflight_worker(dlm, res);
+                       spin_unlock(&res->spinlock);
                }
-               spin_unlock(&res->spinlock);
        } else {
                if (res)
                        dlm_lockres_put(res);
index 3d90ad7..58eaa5c 100644 (file)
@@ -1723,8 +1723,8 @@ int dlm_master_requery_handler(struct o2net_msg *msg, u32 len, void *data,
                        } else {
                                dispatched = 1;
                                __dlm_lockres_grab_inflight_worker(dlm, res);
+                               spin_unlock(&res->spinlock);
                        }
-                       spin_unlock(&res->spinlock);
                } else {
                        /* put.. incase we are not the master */
                        spin_unlock(&res->spinlock);