From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xue jiufei Date: Fri, 18 Dec 2015 11:26:45 +0800 Subject: [Ocfs2-devel] [PATCH] ocfs2/dlm: return appropriate value when dlm_grab() returns NULL Message-ID: <56737CF5.8070304@huawei.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com Function 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 Reviewed-by: Joseph Qi Reviewed-by: Yiwen Jiang --- fs/ocfs2/dlm/dlmmaster.c | 2 +- fs/ocfs2/dlm/dlmunlock.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c index ce38b4c..c43da7f 100644 --- a/fs/ocfs2/dlm/dlmmaster.c +++ b/fs/ocfs2/dlm/dlmmaster.c @@ -3048,7 +3048,7 @@ int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data, int ret = 0; if (!dlm_grab(dlm)) - return -EINVAL; + return 0; name = migrate->name; namelen = migrate->namelen; diff --git a/fs/ocfs2/dlm/dlmunlock.c b/fs/ocfs2/dlm/dlmunlock.c index 2e3c9db..1082b2c 100644 --- a/fs/ocfs2/dlm/dlmunlock.c +++ b/fs/ocfs2/dlm/dlmunlock.c @@ -421,7 +421,7 @@ int dlm_unlock_lock_handler(struct o2net_msg *msg, u32 len, void *data, } if (!dlm_grab(dlm)) - return DLM_REJECTED; + return DLM_FORWARD; mlog_bug_on_msg(!dlm_domain_fully_joined(dlm), "Domain %s not fully joined!\n", dlm->name); -- 1.8.4.3