------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff88804675a898, owner = 0x0, curr 0xffff88801f924980, list empty
WARNING: kernel/locking/rwsem.c:1381 at 0x0, CPU#0: syz.0.18/5550
Modules linked in:
CPU: 0 UID: 0 PID: 5550 Comm: syz.0.18 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__up_write kernel/locking/rwsem.c:1380 [inline]
RIP: 0010:up_write+0x38a/0x410 kernel/locking/rwsem.c:1643
Code: 6b 8b 49 c7 c2 00 24 6b 8b 4c 0f 44 d0 48 8b 7c 24 08 48 c7 c6 20 25 6b 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 98 a0 eb 02 e9 66 fd ff ff 48 c7 c1
RSP: 0018:ffffc9000cbd7d80 EFLAGS: 00010246
RAX: ffffffff8b6b23e0 RBX: ffff88804675a898 RCX: ffff88804675a898
RDX: 0000000000000000 RSI: ffffffff8b6b2520 RDI: ffffffff8f848bb0
RBP: ffff88804675a8f0 R08: 0000000000000000 R09: ffff88801f924980
R10: ffffffff8b6b23e0 R11: ffffed1008ceb515 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff88804675a898 R15: 1ffff11008ceb514
FS:  00007fc9ccb4c6c0(0000) GS:ffff88808d683000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc9ccb4bfc8 CR3: 0000000058fc6000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 inode_unlock include/linux/fs.h:1037 [inline]
 end_dirop fs/namei.c:2888 [inline]
 end_creating include/linux/namei.h:126 [inline]
 end_creating_path fs/namei.c:4922 [inline]
 do_mkdirat+0x2f4/0x4b0 fs/namei.c:5169
 __do_sys_mkdir fs/namei.c:5191 [inline]
 __se_sys_mkdir fs/namei.c:5189 [inline]
 __x64_sys_mkdir+0x6c/0x80 fs/namei.c:5189
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc9cbd8f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc9ccb4c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007fc9cbfe6090 RCX: 00007fc9cbd8f7c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000040
RBP: 00007fc9cbe13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc9cbfe6128 R14: 00007fc9cbfe6090 R15: 00007ffe60b03128
 </TASK>
----------------
Code disassembly (best guess):
   0:	6b 8b 49 c7 c2 00 24 	imul   $0x24,0xc2c749(%rbx),%ecx
   7:	6b 8b 4c 0f 44 d0 48 	imul   $0x48,-0x2fbbf0b4(%rbx),%ecx
   e:	8b 7c 24 08          	mov    0x8(%rsp),%edi
  12:	48 c7 c6 20 25 6b 8b 	mov    $0xffffffff8b6b2520,%rsi
  19:	48 8b 14 24          	mov    (%rsp),%rdx
  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 98 a0 eb 02       	call   0x2eba0d0
  38:	e9 66 fd ff ff       	jmp    0xfffffda3
  3d:	48                   	rex.W
  3e:	c7                   	.byte 0xc7
  3f:	c1                   	.byte 0xc1