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DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff888044cfbb18, owner = 0x0, curr 0xffff88803b670000, list not empty
WARNING: kernel/locking/rwsem.c:1413 at __up_write kernel/locking/rwsem.c:1412 [inline], CPU#0: syz.0.0/5313
WARNING: kernel/locking/rwsem.c:1413 at up_write+0x35c/0x4a0 kernel/locking/rwsem.c:1688, CPU#0: syz.0.0/5313
Modules linked in:
CPU: 0 UID: 0 PID: 5313 Comm: syz.0.0 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:1412 [inline]
RIP: 0010:up_write+0x40f/0x4a0 kernel/locking/rwsem.c:1688
Code: ed 8b 49 c7 c2 60 08 ed 8b 4c 0f 44 d0 48 8b 7c 24 10 48 c7 c6 00 0b ed 8b 48 8b 14 24 48 8b 4c 24 08 4d 89 e0 4d 89 f9 41 52 <67> 48 0f b9 3a 48 83 c4 08 e8 e3 69 30 03 e9 d6 fc ff ff 48 c7 c1
RSP: 0018:ffffc9000dbbfc60 EFLAGS: 00010246
RAX: ffffffff8bed0880 RBX: ffff888044cfbb18 RCX: ffff888044cfbb18
RDX: 0000000000000000 RSI: ffffffff8bed0b00 RDI: ffffffff905be270
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffff88803b670000
R10: ffffffff8bed0880 R11: ffffed100899f765 R12: 0000000000000000
R13: ffff888044cfbb20 R14: ffff888044cfbb70 R15: ffff88803b670000
FS:  00007f9b2b20e6c0(0000) GS:ffff88808c526000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fac4d393000 CR3: 0000000012bb9000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 inode_unlock include/linux/fs.h:1035 [inline]
 __unlock_mount fs/namespace.c:2808 [inline]
 unlock_mount fs/namespace.c:2818 [inline]
 do_new_mount_fc fs/namespace.c:3795 [inline]
 do_new_mount+0x82d/0xdc0 fs/namespace.c:3848
 do_mount fs/namespace.c:4181 [inline]
 __do_sys_mount fs/namespace.c:4397 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4374
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9b2a39e0d9
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:00007f9b2b20dfe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f9b2a626090 RCX: 00007f9b2a39e0d9
RDX: 00002000000000c0 RSI: 0000200000000080 RDI: 0000000000000000
RBP: 00007f9b2a435024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9b2a626128 R14: 00007f9b2a626090 R15: 00007ffd924d68d8
 </TASK>
----------------
Code disassembly (best guess):
   0:	ed                   	in     (%dx),%eax
   1:	8b 49 c7             	mov    -0x39(%rcx),%ecx
   4:	c2 60 08             	ret    $0x860
   7:	ed                   	in     (%dx),%eax
   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:	10 48 c7             	adc    %cl,-0x39(%rax)
  14:	c6 00 0b             	movb   $0xb,(%rax)
  17:	ed                   	in     (%dx),%eax
  18:	8b 48 8b             	mov    -0x75(%rax),%ecx
  1b:	14 24                	adc    $0x24,%al
  1d:	48 8b 4c 24 08       	mov    0x8(%rsp),%rcx
  22:	4d 89 e0             	mov    %r12,%r8
  25:	4d 89 f9             	mov    %r15,%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 e3 69 30 03       	call   0x3306a1b
  38:	e9 d6 fc ff ff       	jmp    0xfffffd13
  3d:	48                   	rex.W
  3e:	c7                   	.byte 0xc7
  3f:	c1                   	.byte 0xc1