From mboxrd@z Thu Jan 1 00:00:00 1970 From: alex chen Date: Tue, 21 Apr 2015 10:54:00 +0800 Subject: [Ocfs2-devel] [PATCH] ocfs2: check if the ocfs2 lock resource be initialized before calling ocfs2_dlm_lock In-Reply-To: <552F6487.4020707@oracle.com> References: <5518C165.10106@huawei.com> <552F6487.4020707@oracle.com> Message-ID: <5535BBC8.5030007@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 Hi Junxiao, On 2015/4/16 15:28, Junxiao Bi wrote: > Hi Alex, > > On 03/30/2015 11:22 AM, alex chen wrote: >> If ocfs2 lockres has not been initialized before calling ocfs2_dlm_lock, >> the lock won't be dropped and then will lead umount hung. The case is >> described below: >> >> ocfs2_mknod >> ocfs2_mknod_locked >> __ocfs2_mknod_locked >> ocfs2_journal_access_di >> Failed because of -ENOMEM or other reasons, the inode lockres >> has not been initialized yet. > > If failed here, is OCFS2_I(inode)->ip_inode_lockres initialized? If not The OCFS2_I(inode)->ip_inode_lockres is initialized as follows: __ocfs2_mknod_locked ocfs2_populate_inode ocfs2_inode_lock_res_init ocfs2_lock_res_init_common So if ocfs2_journal_access_di is failed, the ip_inode_lockres will not be initialized. In this situation, we should not allocate a new dlm lockres through calling ocfs2_dlm_lock() in __ocfs2_cluster_lock(), otherwise it will lead umount hung. So we need bread __ocfs2_cluster_lock() if the inode lockres is not be initialized, that is the condition (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED)) is TRUE. > how can you break __ocfs2_cluster_lock with the following condition? > > if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED)) > > Thanks, > Junxiao. > >> >> iput(inode) >> ocfs2_evict_inode >> ocfs2_delete_inode >> ocfs2_inode_lock >> ocfs2_inode_lock_full_nested >> __ocfs2_cluster_lock >> Succeeds and allocates a new dlm lockres. >> ocfs2_clear_inode >> ocfs2_open_unlock >> ocfs2_drop_inode_locks >> ocfs2_drop_lock >> Since lockres has not been initialized, the lock >> can't be dropped and the lockres can't be >> migrated, thus umount will hang forever. >> >> Signed-off-by: Alex Chen >> Reviewed-by: Joseph Qi >> Reviewed-by: joyce.xue >> >> --- >> fs/ocfs2/dlmglue.c | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c >> index 11849a4..8b23aa2 100644 >> --- a/fs/ocfs2/dlmglue.c >> +++ b/fs/ocfs2/dlmglue.c >> @@ -1391,6 +1391,11 @@ static int __ocfs2_cluster_lock(struct ocfs2_super *osb, >> int noqueue_attempted = 0; >> int dlm_locked = 0; >> >> + if (!(lockres->l_flags & OCFS2_LOCK_INITIALIZED)) { >> + mlog_errno(-EINVAL); >> + return -EINVAL; >> + } >> + >> ocfs2_init_mask_waiter(&mw); >> >> if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB) >> > > > . >