------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON(tmp < 0): count = 0xffffffffffffff00, magic = 0xffff888042f8d058, owner = 0x0, curr 0xffff88801f9e8000, list empty
WARNING: CPU: 0 PID: 5324 at kernel/locking/rwsem.c:1359 __up_read+0x3ea/0x680 kernel/locking/rwsem.c:1359
Modules linked in:
CPU: 0 UID: 0 PID: 5324 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~bpo12+1 04/01/2014
RIP: 0010:__up_read+0x3ea/0x680 kernel/locking/rwsem.c:1359
Code: d0 48 c7 c7 20 ff 6a 8b 48 c7 c6 20 01 6b 8b 48 8b 54 24 08 48 8b 0c 24 4d 89 f8 4d 89 f1 41 52 e8 fb 3c e6 ff 48 83 c4 08 90 <0f> 0b 90 90 e9 71 fe ff ff c6 05 d4 18 eb 0d 01 90 48 89 df be 08
RSP: 0018:ffffc9000d57f940 EFLAGS: 00010292
RAX: cdf8f9fa1a8ff900 RBX: ffff888042f8d058 RCX: ffff88801f9e8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc9000d57f9f8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff1bfa650 R12: ffffffffffffff00
R13: ffff888042f8d0b0 R14: ffff88801f9e8000 R15: 0000000000000000
FS:  00007f6d8e65f6c0(0000) GS:ffff88808d301000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6d8e65efc8 CR3: 000000003e9f3000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 inode_unlock_shared include/linux/fs.h:1005 [inline]
 lookup_slow+0x5e/0x70 fs/namei.c:1834
 walk_component fs/namei.c:2151 [inline]
 link_path_walk+0x935/0xea0 fs/namei.c:2519
 path_parentat fs/namei.c:2723 [inline]
 __filename_parentat+0x246/0x670 fs/namei.c:2747
 filename_parentat fs/namei.c:2765 [inline]
 filename_create+0xd2/0x3c0 fs/namei.c:4207
 do_mkdirat+0xa0/0x590 fs/namei.c:4478
 __do_sys_mkdirat fs/namei.c:4503 [inline]
 __se_sys_mkdirat fs/namei.c:4501 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4501
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6d8d78eec9
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:00007f6d8e65f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f6d8d9e6180 RCX: 00007f6d8d78eec9
RDX: 0000000000000000 RSI: 0000200000000240 RDI: ffffffffffffff9c
RBP: 00007f6d8d811f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6d8d9e6218 R14: 00007f6d8d9e6180 R15: 00007fff9941e3b8
 </TASK>