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DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff888046a449b8, owner = 0x0, curr 0xffff888035fb8000, list empty
WARNING: kernel/locking/rwsem.c:1381 at __up_write kernel/locking/rwsem.c:1380 [inline], CPU#0: syz.0.25/5584
WARNING: kernel/locking/rwsem.c:1381 at up_write+0x2d6/0x410 kernel/locking/rwsem.c:1643, CPU#0: syz.0.25/5584
Modules linked in:
CPU: 0 UID: 0 PID: 5584 Comm: syz.0.25 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:__up_write kernel/locking/rwsem.c:1380 [inline]
RIP: 0010:up_write+0x388/0x410 kernel/locking/rwsem.c:1643
Code: ac 8b 49 c7 c2 a0 e6 ac 8b 4c 0f 44 d0 48 8b 7c 24 08 48 c7 c6 00 e9 ac 8b 48 8b 14 24 4c 89 f1 4d 89 e0 4c 8b 4c 24 10 41 52 <67> 48 0f b9 3a 48 83 c4 08 e8 9a 16 ff 02 e9 67 fd ff ff 48 c7 c1
RSP: 0018:ffffc90002cd7d80 EFLAGS: 00010246
RAX: ffffffff8bace680 RBX: ffff888046a449b8 RCX: ffff888046a449b8
RDX: 0000000000000000 RSI: ffffffff8bace900 RDI: ffffffff8ff28780
RBP: ffff888046a44a10 R08: 0000000000000000 R09: ffff888035fb8000
R10: ffffffff8bace680 R11: ffffed1008d48939 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff888046a449b8 R15: 1ffff11008d48938
FS:  00007f62d55fe6c0(0000) GS:ffff88808cce8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f62d55fdff8 CR3: 0000000055677000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 inode_unlock include/linux/fs.h:1037 [inline]
 end_dirop fs/namei.c:2897 [inline]
 end_creating include/linux/namei.h:126 [inline]
 end_creating_path fs/namei.c:4931 [inline]
 do_mkdirat+0x2fb/0x4b0 fs/namei.c:5178
 __do_sys_mkdir fs/namei.c:5200 [inline]
 __se_sys_mkdir fs/namei.c:5198 [inline]
 __x64_sys_mkdir+0x6c/0x80 fs/namei.c:5198
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f62d5f9af79
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:00007f62d55fe028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f62d6216090 RCX: 00007f62d5f9af79
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000040
RBP: 00007f62d60316e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f62d6216128 R14: 00007f62d6216090 R15: 00007fffbed45998
 </TASK>
----------------
Code disassembly (best guess):
   0:	ac                   	lods   %ds:(%rsi),%al
   1:	8b 49 c7             	mov    -0x39(%rcx),%ecx
   4:	c2 a0 e6             	ret    $0xe6a0
   7:	ac                   	lods   %ds:(%rsi),%al
   8:	8b 4c 0f 44          	mov    0x44(%rdi,%rcx,1),%ecx
   c:	d0 48 8b             	rorb   $1,-0x75(%rax)
   f:	7c 24                	jl     0x35
  11:	08 48 c7             	or     %cl,-0x39(%rax)
  14:	c6 00 e9             	movb   $0xe9,(%rax)
  17:	ac                   	lods   %ds:(%rsi),%al
  18:	8b 48 8b             	mov    -0x75(%rax),%ecx
  1b:	14 24                	adc    $0x24,%al
  1d:	4c 89 f1             	mov    %r14,%rcx
  20:	4d 89 e0             	mov    %r12,%r8
  23:	4c 8b 4c 24 10       	mov    0x10(%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 9a 16 ff 02       	call   0x2ff16d2
  38:	e9 67 fd ff ff       	jmp    0xfffffda4
  3d:	48                   	rex.W
  3e:	c7                   	.byte 0xc7
  3f:	c1                   	.byte 0xc1