Commits
Xue jiufei committed c372f2193a2
ocfs2/dlm: return appropriate value when dlm_grab() returns NULL
dlm_grab() may return NULL when the node is doing unmount. When doing
code review, we found that some dlm handlers may return error to caller
when dlm_grab() returns NULL and make caller BUG or other problems.
Here is an example:
Node 1 Node 2
receives migration message
from node 3, and send
migrate request to others
start unmounting
receives migrate request
from node 1 and call
dlm_migrate_request_handler()
unmount thread unregisters
domain handlers and removes
dlm_context from dlm_domains
dlm_migrate_request_handlers()
returns -EINVAL to node 1
Exit migration neither clearing the
migration state nor sending
assert master message to node 3 which
cause node 3 hung.
Signed-off-by: Jiufei Xue <xuejiufei@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>