diff options
author | Eric Ren <zren@suse.com> | 2017-06-23 15:08:55 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-06-23 16:15:55 -0700 |
commit | 8818efaaacb78c60a9d90c5705b6c99b75d7d442 (patch) | |
tree | e56111444a5fe6af40154a0e3cfd0a82518f564a /fs/ocfs2/dlmglue.c | |
parent | 3b7b314053d021601940c50b07f5f1423ae67e21 (diff) |
ocfs2: fix deadlock caused by recursive locking in xattr
Another deadlock path caused by recursive locking is reported. This
kind of issue was introduced since commit 743b5f1434f5 ("ocfs2: take
inode lock in ocfs2_iop_set/get_acl()"). Two deadlock paths have been
fixed by commit b891fa5024a9 ("ocfs2: fix deadlock issue when taking
inode lock at vfs entry points"). Yes, we intend to fix this kind of
case in incremental way, because it's hard to find out all possible
paths at once.
This one can be reproduced like this. On node1, cp a large file from
home directory to ocfs2 mountpoint. While on node2, run
setfacl/getfacl. Both nodes will hang up there. The backtraces:
On node1:
__ocfs2_cluster_lock.isra.39+0x357/0x740 [ocfs2]
ocfs2_inode_lock_full_nested+0x17d/0x840 [ocfs2]
ocfs2_write_begin+0x43/0x1a0 [ocfs2]
generic_perform_write+0xa9/0x180
__generic_file_write_iter+0x1aa/0x1d0
ocfs2_file_write_iter+0x4f4/0xb40 [ocfs2]
__vfs_write+0xc3/0x130
vfs_write+0xb1/0x1a0
SyS_write+0x46/0xa0
On node2:
__ocfs2_cluster_lock.isra.39+0x357/0x740 [ocfs2]
ocfs2_inode_lock_full_nested+0x17d/0x840 [ocfs2]
ocfs2_xattr_set+0x12e/0xe80 [ocfs2]
ocfs2_set_acl+0x22d/0x260 [ocfs2]
ocfs2_iop_set_acl+0x65/0xb0 [ocfs2]
set_posix_acl+0x75/0xb0
posix_acl_xattr_set+0x49/0xa0
__vfs_setxattr+0x69/0x80
__vfs_setxattr_noperm+0x72/0x1a0
vfs_setxattr+0xa7/0xb0
setxattr+0x12d/0x190
path_setxattr+0x9f/0xb0
SyS_setxattr+0x14/0x20
Fix this one by using ocfs2_inode_{lock|unlock}_tracker, which is
exported by commit 439a36b8ef38 ("ocfs2/dlmglue: prepare tracking logic
to avoid recursive cluster lock").
Link: http://lkml.kernel.org/r/20170622014746.5815-1-zren@suse.com
Fixes: 743b5f1434f5 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()")
Signed-off-by: Eric Ren <zren@suse.com>
Reported-by: Thomas Voegtle <tv@lio96.de>
Tested-by: Thomas Voegtle <tv@lio96.de>
Reviewed-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mfasheh@versity.com>
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>
Diffstat (limited to 'fs/ocfs2/dlmglue.c')
-rw-r--r-- | fs/ocfs2/dlmglue.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c index 3b7c937a36b5..4689940a953c 100644 --- a/fs/ocfs2/dlmglue.c +++ b/fs/ocfs2/dlmglue.c @@ -2591,6 +2591,10 @@ void ocfs2_inode_unlock_tracker(struct inode *inode, struct ocfs2_lock_res *lockres; lockres = &OCFS2_I(inode)->ip_inode_lockres; + /* had_lock means that the currect process already takes the cluster + * lock previously. If had_lock is 1, we have nothing to do here, and + * it will get unlocked where we got the lock. + */ if (!had_lock) { ocfs2_remove_holder(lockres, oh); ocfs2_inode_unlock(inode, ex); |