possible deadlock in ocfs2_xattr_set

Status: upstream: reported on 2024/09/25 09:02
Reported-by: syzbot+c0d46b51c54922dc038f@syzkaller.appspotmail.com
First crash: 684d, last: 4h34m
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 possible deadlock in ocfs2_xattr_set 4 485 2d08h 695d 0/3 upstream: reported on 2024/09/14 01:11
upstream possible deadlock in ocfs2_xattr_set prio:high ocfs2 4 9331 12h09m 699d 0/29 upstream: reported on 2024/09/10 05:07
linux-6.6 possible deadlock in ocfs2_xattr_set 4 447 4d19h 416d 0/2 upstream: reported on 2025/06/19 18:15

Sample crash report:
ocfs2: Mounting device (7,2) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.2.700/7223 is trying to acquire lock:
ffff88804b549808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
ffff88804b549808 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}, at: ocfs2_xattr_set+0xbe4/0x1390 fs/ocfs2/xattr.c:3626

but task is already holding lock:
ffff888054be06f8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_xattr_set+0x491/0x1390 fs/ocfs2/xattr.c:3587

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&oi->ip_xattr_sem){++++}-{3:3}:
       down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520
       ocfs2_init_acl+0x307/0x770 fs/ocfs2/acl.c:365
       ocfs2_mknod+0x18e0/0x2580 fs/ocfs2/namei.c:410
       ocfs2_create+0x1b6/0x4b0 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3490 [inline]
       open_last_lookups fs/namei.c:3558 [inline]
       path_openat+0x11b9/0x2f10 fs/namei.c:3788
       do_filp_open+0x1ee/0x420 fs/namei.c:3818
       do_sys_openat2+0x14b/0x4f0 fs/open.c:1320
       do_sys_open fs/open.c:1336 [inline]
       __do_sys_openat fs/open.c:1352 [inline]
       __se_sys_openat fs/open.c:1347 [inline]
       __x64_sys_openat+0x135/0x160 fs/open.c:1347
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #2 (&journal->j_trans_barrier){.+.+}-{3:3}:
       down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520
       ocfs2_start_trans+0x3a4/0x6f0 fs/ocfs2/journal.c:374
       ocfs2_modify_bh+0xe0/0x4c0 fs/ocfs2/quota_local.c:101
       ocfs2_local_read_info+0x1499/0x1820 fs/ocfs2/quota_local.c:764
       dquot_load_quota_sb+0x72f/0xa80 fs/quota/dquot.c:2495
       dquot_load_quota_inode+0x2d3/0x5c0 fs/quota/dquot.c:2532
       ocfs2_enable_quotas+0x1c0/0x4a0 fs/ocfs2/super.c:926
       ocfs2_fill_super+0x40fe/0x5010 fs/ocfs2/super.c:1139
       mount_bdev+0x28a/0x3c0 fs/super.c:1443
       legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
       vfs_get_tree+0x88/0x270 fs/super.c:1573
       do_new_mount+0x247/0xa40 fs/namespace.c:3078
       do_mount fs/namespace.c:3421 [inline]
       __do_sys_mount fs/namespace.c:3629 [inline]
       __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (sb_internal#5){.+.+}-{0:0}:
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1891 [inline]
       sb_start_intwrite include/linux/fs.h:2013 [inline]
       ocfs2_start_trans+0x2a5/0x6f0 fs/ocfs2/journal.c:372
       ocfs2_remove_btree_range+0x812/0x15e0 fs/ocfs2/alloc.c:5752
       ocfs2_commit_truncate+0xba2/0x1e00 fs/ocfs2/alloc.c:7353
       ocfs2_truncate_file+0xdf0/0x1660 fs/ocfs2/file.c:505
       ocfs2_setattr+0x16f8/0x1d90 fs/ocfs2/file.c:1212
       notify_change+0xca0/0xf90 fs/attr.c:499
       do_truncate+0x1ac/0x240 fs/open.c:65
       vfs_truncate+0x262/0x2f0 fs/open.c:111
       do_sys_truncate+0xf2/0x1c0 fs/open.c:134
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3095 [inline]
       check_prevs_add kernel/locking/lockdep.c:3214 [inline]
       validate_chain kernel/locking/lockdep.c:3830 [inline]
       __lock_acquire+0x2d18/0x7c40 kernel/locking/lockdep.c:5063
       lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676
       down_write+0x36/0x60 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:758 [inline]
       ocfs2_xattr_set+0xbe4/0x1390 fs/ocfs2/xattr.c:3626
       ocfs2_set_acl+0x4d4/0x580 fs/ocfs2/acl.c:254
       ocfs2_iop_set_acl+0x190/0x2b0 fs/ocfs2/acl.c:285
       set_posix_acl fs/posix_acl.c:1160 [inline]
       posix_acl_xattr_set+0x388/0x3f0 fs/posix_acl.c:1189
       __vfs_setxattr+0x3d8/0x410 fs/xattr.c:182
       __vfs_setxattr_noperm+0x126/0x5e0 fs/xattr.c:216
       vfs_setxattr+0x167/0x2e0 fs/xattr.c:309
       do_setxattr fs/xattr.c:594 [inline]
       setxattr+0x2a3/0x330 fs/xattr.c:617
       path_setxattr+0x147/0x290 fs/xattr.c:636
       __do_sys_setxattr fs/xattr.c:652 [inline]
       __se_sys_setxattr fs/xattr.c:648 [inline]
       __x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:648
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Chain exists of:
  &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8 --> &journal->j_trans_barrier --> &oi->ip_xattr_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_xattr_sem);
                               lock(&journal->j_trans_barrier);
                               lock(&oi->ip_xattr_sem);
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#8);

 *** DEADLOCK ***

3 locks held by syz.2.700/7223:
 #0: ffff88807955c460 (sb_writers#30){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402
 #1: ffff888054be09c8 (&type->i_mutex_dir_key#24){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff888054be09c8 (&type->i_mutex_dir_key#24){+.+.}-{3:3}, at: vfs_setxattr+0x140/0x2e0 fs/xattr.c:308
 #2: ffff888054be06f8 (&oi->ip_xattr_sem){++++}-{3:3}, at: ocfs2_xattr_set+0x491/0x1390 fs/ocfs2/xattr.c:3587

stack backtrace:
CPU: 0 PID: 7223 Comm: syz.2.700 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2170
 check_prev_add kernel/locking/lockdep.c:3095 [inline]
 check_prevs_add kernel/locking/lockdep.c:3214 [inline]
 validate_chain kernel/locking/lockdep.c:3830 [inline]
 __lock_acquire+0x2d18/0x7c40 kernel/locking/lockdep.c:5063
 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676
 down_write+0x36/0x60 kernel/locking/rwsem.c:1573
 inode_lock include/linux/fs.h:758 [inline]
 ocfs2_xattr_set+0xbe4/0x1390 fs/ocfs2/xattr.c:3626
 ocfs2_set_acl+0x4d4/0x580 fs/ocfs2/acl.c:254
 ocfs2_iop_set_acl+0x190/0x2b0 fs/ocfs2/acl.c:285
 set_posix_acl fs/posix_acl.c:1160 [inline]
 posix_acl_xattr_set+0x388/0x3f0 fs/posix_acl.c:1189
 __vfs_setxattr+0x3d8/0x410 fs/xattr.c:182
 __vfs_setxattr_noperm+0x126/0x5e0 fs/xattr.c:216
 vfs_setxattr+0x167/0x2e0 fs/xattr.c:309
 do_setxattr fs/xattr.c:594 [inline]
 setxattr+0x2a3/0x330 fs/xattr.c:617
 path_setxattr+0x147/0x290 fs/xattr.c:636
 __do_sys_setxattr fs/xattr.c:652 [inline]
 __se_sys_setxattr fs/xattr.c:648 [inline]
 __x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:648
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6bc819e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6bc90a4028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f6bc8425fa0 RCX: 00007f6bc819e0d9
RDX: 0000200000000100 RSI: 0000200000002a40 RDI: 0000200000002a00
RBP: 00007f6bc8235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000024 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6bc8426038 R14: 00007f6bc8425fa0 R15: 00007ffe58688468
 </TASK>
OCFS2: ERROR (device loop2): int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *, handle_t *, u32, u32, struct ocfs2_suballoc_result *): Chain allocator dinode 71 has 16777215 used bits but only 1024 total
On-disk corruption discovered. Please run fsck.ocfs2 once the filesystem is unmounted.
OCFS2: File system is now read-only.
(syz.2.700,7223,1):ocfs2_claim_suballoc_bits:2015 ERROR: status = -30
(syz.2.700,7223,1):__ocfs2_claim_clusters:2387 ERROR: status = -30
(syz.2.700,7223,1):__ocfs2_claim_clusters:2395 ERROR: status = -30
(syz.2.700,7223,1):ocfs2_block_group_alloc_contig:455 ERROR: status = -30
(syz.2.700,7223,0):ocfs2_block_group_alloc:727 ERROR: status = -30
(syz.2.700,7223,1):ocfs2_block_group_alloc:780 ERROR: status = -30
(syz.2.700,7223,0):ocfs2_reserve_suballoc_bits:855 ERROR: status = -30
(syz.2.700,7223,0):ocfs2_reserve_suballoc_bits:872 ERROR: status = -30
(syz.2.700,7223,0):ocfs2_reserve_new_metadata_blocks:1012 ERROR: status = -30
(syz.2.700,7223,0):ocfs2_reserve_new_metadata_blocks:1035 ERROR: status = -30
(syz.2.700,7223,1):ocfs2_init_xattr_set_ctxt:3284 ERROR: status = -30
(syz.2.700,7223,1):ocfs2_xattr_set:3641 ERROR: status = -30

Crashes (914):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/10 11:52 linux-6.1.y e4f7d8be268e 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/08/10 07:15 linux-6.1.y e4f7d8be268e 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/08/06 18:57 linux-6.1.y 03f3a99e8e93 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/27 12:32 linux-6.1.y dc5c83b7f5f8 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/20 11:25 linux-6.1.y 090666d3cc90 de6a700d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/15 17:07 linux-6.1.y 090666d3cc90 a4ed0f4f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/14 15:56 linux-6.1.y 090666d3cc90 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/14 00:46 linux-6.1.y 090666d3cc90 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/10 18:47 linux-6.1.y 090666d3cc90 99e64375 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/09 21:40 linux-6.1.y 090666d3cc90 a0c310a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/09 10:18 linux-6.1.y 090666d3cc90 b9f1ceaa .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/07 00:42 linux-6.1.y 090666d3cc90 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/04 14:47 linux-6.1.y 090666d3cc90 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/03 21:50 linux-6.1.y fdb6fcb41cc7 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/02 17:19 linux-6.1.y fdb6fcb41cc7 2b70b115 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/07/02 17:14 linux-6.1.y fdb6fcb41cc7 2b70b115 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/06/30 02:56 linux-6.1.y fdb6fcb41cc7 fff8d0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/06/25 05:39 linux-6.1.y fdb6fcb41cc7 cfa969bf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/06/23 04:00 linux-6.1.y fdb6fcb41cc7 5a630be6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/06/22 18:25 linux-6.1.y fdb6fcb41cc7 5a630be6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/06/18 11:08 linux-6.1.y 228da13e907e a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/06/17 23:15 linux-6.1.y 228da13e907e b62b3ded .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/06/16 04:35 linux-6.1.y 228da13e907e 50bb0618 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/06/12 17:02 linux-6.1.y 228da13e907e 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2024/09/25 09:02 linux-6.1.y e526b12bf916 349a68c4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan possible deadlock in ocfs2_xattr_set
2026/08/09 17:34 linux-6.1.y e4f7d8be268e 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/08/09 15:48 linux-6.1.y e4f7d8be268e 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/07/27 13:58 linux-6.1.y dc5c83b7f5f8 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/07/12 18:52 linux-6.1.y 090666d3cc90 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/07/11 18:36 linux-6.1.y 090666d3cc90 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/07/11 16:42 linux-6.1.y 090666d3cc90 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/07/11 07:03 linux-6.1.y 090666d3cc90 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/07/10 15:38 linux-6.1.y 090666d3cc90 99e64375 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/07/10 05:29 linux-6.1.y 090666d3cc90 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/07/01 05:03 linux-6.1.y fdb6fcb41cc7 00a5cf1c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/30 12:34 linux-6.1.y fdb6fcb41cc7 fff8d0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/30 03:59 linux-6.1.y fdb6fcb41cc7 fff8d0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/28 09:27 linux-6.1.y fdb6fcb41cc7 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/24 01:33 linux-6.1.y fdb6fcb41cc7 042555ff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/23 13:46 linux-6.1.y fdb6fcb41cc7 4b1d8f01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/22 20:06 linux-6.1.y fdb6fcb41cc7 5a630be6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/22 15:49 linux-6.1.y fdb6fcb41cc7 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/22 01:21 linux-6.1.y fdb6fcb41cc7 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/20 16:34 linux-6.1.y fdb6fcb41cc7 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/19 02:49 linux-6.1.y 228da13e907e a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/18 05:09 linux-6.1.y 228da13e907e b62b3ded .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
2026/06/14 20:27 linux-6.1.y 228da13e907e 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 possible deadlock in ocfs2_xattr_set
* Struck through repros no longer work on HEAD.