From c372f2193a2e73d5936bf37259ae63ca388b4cbc Mon Sep 17 00:00:00 2001 From: Xue jiufei Date: Thu, 14 Jan 2016 15:17:29 -0800 Subject: [PATCH] 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 Reviewed-by: Joseph Qi Reviewed-by: Yiwen Jiang Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- 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 1fc172f89872..6f0748122117 100644 --- a/fs/ocfs2/dlm/dlmmaster.c +++ b/fs/ocfs2/dlm/dlmmaster.c @@ -3050,7 +3050,7 @@ 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 2e3c9dbab68c..1082b2c3014b 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); -- 2.30.2