ocfs2: fix deadlock caused by recursive locking in xattr
commit 8818efaa upstream. Another deadlock path caused by recursive locking is reported. This kind of issue was introduced since commit 743b5f14 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()"). Two deadlock paths have been fixed by commit b891fa50 ("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 439a36b8 ("ocfs2/dlmglue: prepare tracking logic to avoid recursive cluster lock"). Link: http://lkml.kernel.org/r/20170622014746.5815-1-zren@suse.com Fixes: 743b5f14 ("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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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