[PATCH 4.9 21/25] ocfs2: fix cluster hang after a node dies

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Changwei Ge <ge.changwei@h3c.com>

commit 1c01967116a678fed8e2c68a6ab82abc8effeddc upstream.

When a node dies, other live nodes have to choose a new master for an
existed lock resource mastered by the dead node.

As for ocfs2/dlm implementation, this is done by function -
dlm_move_lockres_to_recovery_list which marks those lock rsources as
DLM_LOCK_RES_RECOVERING and manages them via a list from which DLM
changes lock resource's master later.

So without invoking dlm_move_lockres_to_recovery_list, no master will be
choosed after dlm recovery accomplishment since no lock resource can be
found through ::resource list.

What's worse is that if DLM_LOCK_RES_RECOVERING is not marked for lock
resources mastered a dead node, it will break up synchronization among
nodes.

So invoke dlm_move_lockres_to_recovery_list again.

Fixs: 'commit ee8f7fcbe638 ("ocfs2/dlm: continue to purge recovery lockres when recovery master goes down")'
Link: http://lkml.kernel.org/r/63ADC13FD55D6546B7DECE290D39E373CED6E0F9@H3CMLB14-EX.srv.huawei-3com.com
Signed-off-by: Changwei Ge <ge.changwei@h3c.com>
Reported-by: Vitaly Mayatskih <v.mayatskih@gmail.com>
Tested-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/ocfs2/dlm/dlmrecovery.c |    1 +
 1 file changed, 1 insertion(+)

--- a/fs/ocfs2/dlm/dlmrecovery.c
+++ b/fs/ocfs2/dlm/dlmrecovery.c
@@ -2419,6 +2419,7 @@ static void dlm_do_local_recovery_cleanu
 					dlm_lockres_put(res);
 					continue;
 				}
+				dlm_move_lockres_to_recovery_list(dlm, res);
 			} else if (res->owner == dlm->node_num) {
 				dlm_free_dead_locks(dlm, res, dead_node);
 				__dlm_lockres_calc_usage(dlm, res);