ocfs2: fix BUG when o2hb_register_callback fails

In dlm_register_domain_handlers, if o2hb_register_callback fails, it
will call dlm_unregister_domain_handlers to unregister.  This will
trigger the BUG_ON in o2hb_unregister_callback because hc_magic is 0.
So we should call o2hb_setup_callback to initialize hc first.

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

diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 7df88a6dd6260ce3741aa27aa28facfa73c1cba7..4f750701bd9a493d483822564b939bb83684b344 100644 (file)
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -1725,12 +1725,13 @@ static int dlm_register_domain_handlers(struct dlm_ctxt *dlm)
 
        o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB,
                            dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI);
+       o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB,
+                           dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI);
+
        status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_down);
        if (status)
                goto bail;
 
-       o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB,
-                           dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI);
        status = o2hb_register_callback(dlm->name, &dlm->dlm_hb_up);
        if (status)
                goto bail;