BUG: Dentry 000000009aada1a5{i=6d48,n=#27976}  still in use (1) [unmount of hugetlbfs hugetlbfs]
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WARNING: CPU: 1 PID: 7561 at fs/dcache.c:1595 umount_check.cold.53+0xd2/0x13f fs/dcache.c:1586
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 7561 Comm: syz-executor.2 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x12d/0x187 lib/dump_stack.c:118
 panic+0x22a/0x4e3 kernel/panic.c:221
 __warn.cold.11+0x25/0x30 kernel/panic.c:582
 report_bug+0x1b0/0x270 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:291
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028
RIP: 0010:umount_check.cold.53+0xd2/0x13f fs/dcache.c:1595
Code: c1 ea 03 80 3c 02 00 75 79 49 81 c4 88 06 00 00 41 89 d8 48 89 f1 41 54 4d 8b 0e 4c 89 ea 48 c7 c7 20 90 35 87 e8 5b d9 aa ff <0f> 0b 58 e9 b0 3b ff ff 48 89 75 d8 e8 7b ff f1 ff 48 8b 75 d8 e9
RSP: 0018:ffff888098e8fbf8 EFLAGS: 00010282
RAX: 0000000000000060 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff89fe01a0
RBP: ffff888098e8fc28 R08: ffffed1015d66159 R09: ffffed1015d66159
R10: ffffed1015d66158 R11: ffff8880aeb30ac7 R12: ffff88807ffe8688
R13: 0000000000006d48 R14: ffffffff886f3de0 R15: ffff88808983a930
 d_walk+0x257/0x6b0 fs/dcache.c:1305
 do_one_tree+0x1f/0x40 fs/dcache.c:1602
 shrink_dcache_for_umount+0x56/0x120 fs/dcache.c:1618
 generic_shutdown_super+0x61/0x330 fs/super.c:447
 kill_anon_super+0x38/0x60 fs/super.c:1106
 kill_litter_super+0x39/0x50 fs/super.c:1115
 deactivate_locked_super+0x77/0xd0 fs/super.c:335
 deactivate_super+0x136/0x150 fs/super.c:366
 cleanup_mnt+0x204/0x440 fs/namespace.c:1102
 __cleanup_mnt+0xd/0x10 fs/namespace.c:1109
 task_work_run+0x108/0x180 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x24e/0x2e0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x4e8/0x5d0 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45cc47
Code: 64 89 04 25 d0 02 00 00 58 5f ff d0 48 89 c7 e8 2f be ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 4d 8c fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffe3ecc3768 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000045cc47
RDX: 0000000000403a90 RSI: 0000000000000002 RDI: 00007ffe3ecc3810
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000009
R10: 0000000000000005 R11: 0000000000000202 R12: 00007ffe3ecc48a0
R13: 0000000001b1d940 R14: 0000000000000000 R15: 00007ffe3ecc48a0
Kernel Offset: disabled
Rebooting in 86400 seconds..