Patch fixes a race that can result in an oops while adding a
lockres to the dlm lockres tracking list.
Bug introduced by mainline commit 
29576f8bb54045be944ba809d4fca1ad77c94165.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
 
        res->last_used = 0;
 
+       spin_lock(&dlm->spinlock);
        list_add_tail(&res->tracking, &dlm->tracking_list);
+       spin_unlock(&dlm->spinlock);
 
        memset(res->lvb, 0, DLM_LVB_LEN);
        memset(res->refmap, 0, sizeof(res->refmap));