------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(lock->magic != lock)
WARNING: CPU: 0 PID: 7975 at kernel/locking/mutex.c:582 __mutex_lock_common kernel/locking/mutex.c:582 [inline]
WARNING: CPU: 0 PID: 7975 at kernel/locking/mutex.c:582 __mutex_lock+0x9f8/0x1350 kernel/locking/mutex.c:747
Modules linked in:
CPU: 0 PID: 7975 Comm: syz-executor.2 Not tainted 6.4.0-syzkaller-11989-g6843306689af #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:582 [inline]
RIP: 0010:__mutex_lock+0x9f8/0x1350 kernel/locking/mutex.c:747
Code: 08 84 d2 0f 85 7e 08 00 00 8b 05 1f fe 87 04 85 c0 0f 85 1b f7 ff ff 48 c7 c6 c0 5d 6c 8a 48 c7 c7 80 5b 6c 8a e8 08 92 29 f7 <0f> 0b e9 01 f7 ff ff 48 8b 7c 24 30 be 08 00 00 00 e8 b2 74 b5 f7
RSP: 0018:ffffc900075e7610 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc90004d79000
RDX: 0000000000040000 RSI: ffffffff814c34f7 RDI: 0000000000000001
RBP: ffff88802ab8c028 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 4f4c5f4755424544 R12: 0000000000000000
R13: dffffc0000000000 R14: ffffc900075e7850 R15: ffff888029d90ef8
FS:  0000000000000000(0000) GS:ffff88802c600000(0063) knlGS:00000000f7f6eb40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000eda7ec00 CR3: 0000000057d17000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 reiserfs_write_lock+0x79/0x100 fs/reiserfs/lock.c:27
 reiserfs_lookup+0x175/0x610 fs/reiserfs/namei.c:364
 lookup_open.isra.0+0x93b/0x1400 fs/namei.c:3470
 open_last_lookups fs/namei.c:3560 [inline]
 path_openat+0x969/0x2710 fs/namei.c:3790
 do_filp_open+0x1ba/0x410 fs/namei.c:3820
 do_sys_openat2+0x160/0x1c0 fs/open.c:1407
 do_sys_open fs/open.c:1422 [inline]
 __do_compat_sys_openat fs/open.c:1482 [inline]
 __se_compat_sys_openat fs/open.c:1480 [inline]
 __ia32_compat_sys_openat+0x143/0x1f0 fs/open.c:1480
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 entry_SYSENTER_compat_after_hwframe+0x70/0x82
RIP: 0023:0xf7f73579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f7f6e5cc EFLAGS: 00000296 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 0000000020000140
RDX: 0000000000141842 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	10 06                	adc    %al,(%rsi)
   2:	03 74 b4 01          	add    0x1(%rsp,%rsi,4),%esi
   6:	10 07                	adc    %al,(%rdi)
   8:	03 74 b0 01          	add    0x1(%rax,%rsi,4),%esi
   c:	10 08                	adc    %cl,(%rax)
   e:	03 74 d8 01          	add    0x1(%rax,%rbx,8),%esi
  1e:	00 51 52             	add    %dl,0x52(%rcx)
  21:	55                   	push   %rbp
  22:	89 e5                	mov    %esp,%ebp
  24:	0f 34                	sysenter
  26:	cd 80                	int    $0x80
* 28:	5d                   	pop    %rbp <-- trapping instruction
  29:	5a                   	pop    %rdx
  2a:	59                   	pop    %rcx
  2b:	c3                   	retq
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	90                   	nop
  2f:	90                   	nop
  30:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi
  37:	8d b4 26 00 00 00 00 	lea    0x0(%rsi,%riz,1),%esi