syzbot

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DEBUG_RWSEMS_WARN_ON(tmp < 0): count = 0xffffffffffffff00, magic = 0xffff888075e92d18, owner = 0x1, curr 0xffff88802c369f00, list not empty
WARNING: kernel/locking/rwsem.c:1389 at __up_read+0x307/0x6b0 kernel/locking/rwsem.c:1389, CPU#0: syz.0.351/7414
Modules linked in:
CPU: 0 UID: 0 PID: 7414 Comm: syz.0.351 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:__up_read+0x3f5/0x6b0 kernel/locking/rwsem.c:1389
Code: 8b 49 c7 c2 40 e6 cc 8b 4c 0f 44 d0 48 8b 7c 24 38 48 c7 c6 c0 e8 cc 8b 48 8b 54 24 30 4c 89 f1 4d 89 f8 4c 8b 4c 24 28 41 52 <67> 48 0f b9 3a 48 83 c4 08 e8 dd 32 0d 03 e9 72 fe ff ff 48 8d 1d
RSP: 0018:ffffc90005857918 EFLAGS: 00010246
RAX: ffffffff8bcce660 RBX: ffff888075e92d70 RCX: ffff888075e92d18
RDX: ffffffffffffff00 RSI: ffffffff8bcce8c0 RDI: ffffffff90338f60
RBP: ffffc900058579e8 R08: 0000000000000001 R09: ffff88802c369f00
R10: ffffffff8bcce660 R11: ffffed100ebd25a5 R12: ffffffffffffff00
R13: 1ffff92000b0af2c R14: ffff888075e92d18 R15: 0000000000000001
FS:  00007fb9e28966c0(0000) GS:ffff8881252a0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efe8ff5f000 CR3: 0000000055c70000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 inode_unlock_shared include/linux/fs.h:1054 [inline]
 lookup_slow+0x5e/0x70 fs/namei.c:1933
 walk_component fs/namei.c:2278 [inline]
 link_path_walk+0xd1e/0x18d0 fs/namei.c:2652
 path_parentat fs/namei.c:2856 [inline]
 __filename_parentat+0x27f/0x6f0 fs/namei.c:2880
 filename_parentat fs/namei.c:2898 [inline]
 filename_create+0xd9/0x370 fs/namei.c:4931
 filename_mkdirat+0xd2/0x510 fs/namei.c:5297
 __do_sys_mkdirat fs/namei.c:5325 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb9e199ce59
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:00007fb9e2896028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fb9e1c16180 RCX: 00007fb9e199ce59
RDX: 00000000000001c0 RSI: 0000200000000240 RDI: ffffffffffffff9c
RBP: 00007fb9e1a32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb9e1c16218 R14: 00007fb9e1c16180 R15: 00007ffd41f5c7f8
 </TASK>
----------------
Code disassembly (best guess):
   0:	8b 49 c7             	mov    -0x39(%rcx),%ecx
   3:	c2 40 e6             	ret    $0xe640
   6:	cc                   	int3
   7:	8b 4c 0f 44          	mov    0x44(%rdi,%rcx,1),%ecx
   b:	d0 48 8b             	rorb   $1,-0x75(%rax)
   e:	7c 24                	jl     0x34
  10:	38 48 c7             	cmp    %cl,-0x39(%rax)
  13:	c6 c0 e8             	mov    $0xe8,%al
  16:	cc                   	int3
  17:	8b 48 8b             	mov    -0x75(%rax),%ecx
  1a:	54                   	push   %rsp
  1b:	24 30                	and    $0x30,%al
  1d:	4c 89 f1             	mov    %r14,%rcx
  20:	4d 89 f8             	mov    %r15,%r8
  23:	4c 8b 4c 24 28       	mov    0x28(%rsp),%r9
  28:	41 52                	push   %r10
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	48 83 c4 08          	add    $0x8,%rsp
  33:	e8 dd 32 0d 03       	call   0x30d3315
  38:	e9 72 fe ff ff       	jmp    0xfffffeaf
  3d:	48                   	rex.W
  3e:	8d                   	.byte 0x8d
  3f:	1d                   	.byte 0x1d