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kernel BUG at lib/lockref.c:189!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 9350 Comm: syz-executor444 Not tainted 5.2.0-next-20190708 #33
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:lockref_mark_dead lib/lockref.c:189 [inline]
RIP: 0010:lockref_mark_dead+0x8b/0xa0 lib/lockref.c:187
Code: 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 04 3c 03 7e 1d c7 43 38 80 ff ff ff 5b 41 5c 5d c3 e8 75 19 38 fe <0f> 0b 48 89 df e8 0b 59 72 fe eb ab e8 a4 59 72 fe eb dc 90 90 55
RSP: 0018:ffff88809004fc90 EFLAGS: 00010293
RAX: ffff88808bcc0300 RBX: ffff8880a69b0520 RCX: ffffffff833a3abf
RDX: 0000000000000000 RSI: ffffffff833a3afb RDI: 0000000000000005
RBP: ffff88809004fca0 R08: ffff88808bcc0300 R09: ffffed1014d360a5
R10: ffffed1014d360a4 R11: ffff8880a69b0523 R12: 0000000000000000
R13: ffff8880a69b0520 R14: ffff8880a69b04a0 R15: 0000000000000000
FS:  000055555571f880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555555738938 CR3: 0000000091be1000 CR4: 00000000001406f0
Call Trace:
 __dentry_kill+0x5f/0x600 fs/dcache.c:560
 shrink_dcache_parent+0x2c9/0x3d0 fs/dcache.c:1565
 vfs_rmdir fs/namei.c:3882 [inline]
 vfs_rmdir+0x26f/0x4f0 fs/namei.c:3857
 do_rmdir+0x39e/0x420 fs/namei.c:3940
 __do_sys_rmdir fs/namei.c:3958 [inline]
 __se_sys_rmdir fs/namei.c:3956 [inline]
 __x64_sys_rmdir+0x36/0x40 fs/namei.c:3956
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x441917
Code: 0f 1f 00 b8 57 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 ad 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 54 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 8d 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffe53fc08f8 EFLAGS: 00000207 ORIG_RAX: 0000000000000054
RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 0000000000441917
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007ffe53fc1a90
RBP: 00000000000024ef R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000005 R11: 0000000000000207 R12: 00007ffe53fc1a90
R13: 00005555557288c0 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 407254279c8c4b61 ]---
RIP: 0010:lockref_mark_dead lib/lockref.c:189 [inline]
RIP: 0010:lockref_mark_dead+0x8b/0xa0 lib/lockref.c:187
Code: 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 04 3c 03 7e 1d c7 43 38 80 ff ff ff 5b 41 5c 5d c3 e8 75 19 38 fe <0f> 0b 48 89 df e8 0b 59 72 fe eb ab e8 a4 59 72 fe eb dc 90 90 55
RSP: 0018:ffff88809004fc90 EFLAGS: 00010293
RAX: ffff88808bcc0300 RBX: ffff8880a69b0520 RCX: ffffffff833a3abf
RDX: 0000000000000000 RSI: ffffffff833a3afb RDI: 0000000000000005
RBP: ffff88809004fca0 R08: ffff88808bcc0300 R09: ffffed1014d360a5
R10: ffffed1014d360a4 R11: ffff8880a69b0523 R12: 0000000000000000
R13: ffff8880a69b0520 R14: ffff8880a69b04a0 R15: 0000000000000000
FS:  000055555571f880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555555738938 CR3: 0000000091be1000 CR4: 00000000001406f0