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WARNING: CPU: 0 PID: 8148 at fs/btrfs/volumes.c:1086 close_fs_devices.part.0.cold+0x11/0x30 fs/btrfs/volumes.c:1086
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 8148 Comm: syz-executor.1 Not tainted 4.19.165-syzkaller #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+0x1fc/0x2fe lib/dump_stack.c:118
 panic+0x26a/0x50e kernel/panic.c:186
 __warn.cold+0x20/0x61 kernel/panic.c:541
 report_bug+0x262/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 fixup_bug arch/x86/kernel/traps.c:173 [inline]
 do_error_trap+0x1d7/0x310 arch/x86/kernel/traps.c:296
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038
RIP: 0010:close_fs_devices.part.0.cold+0x11/0x30 fs/btrfs/volumes.c:1086
Code: c7 c7 e0 f7 a4 88 e8 fa a5 56 fe 0f 0b 49 c7 c4 ea ff ff ff e9 d7 06 ff ff e8 f8 ab 6b fe 48 c7 c7 e0 f7 a4 88 e8 db a5 56 fe <0f> 0b e9 b4 0e ff ff e8 e0 ab 6b fe 48 c7 c7 e0 f7 a4 88 e8 c3 a5
RSP: 0018:ffff88809bc97b68 EFLAGS: 00010286
RAX: 0000000000000024 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff814fdd11 RDI: ffffed1013792f5f
RBP: ffff8880b3d06a40 R08: 0000000000000024 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8880b28a9040 R14: ffff888094602960 R15: ffff888091de7200
 close_fs_devices fs/btrfs/volumes.c:1113 [inline]
 btrfs_close_devices+0x95/0x1f0 fs/btrfs/volumes.c:1099
 close_ctree+0x3c8/0x850 fs/btrfs/disk-io.c:4047
 generic_shutdown_super+0x144/0x370 fs/super.c:456
 kill_anon_super+0x36/0x60 fs/super.c:1032
 btrfs_kill_super+0x49/0x550 fs/btrfs/super.c:2213
 deactivate_locked_super+0x94/0x160 fs/super.c:329
 deactivate_super+0x174/0x1a0 fs/super.c:360
 cleanup_mnt+0x1a8/0x290 fs/namespace.c:1098
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x460c47
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 ad 89 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff07ff9fa8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000460c47
RDX: 00000000004033a8 RSI: 0000000000000002 RDI: 00007fff07ffa050
RBP: 00000000000d12cb R08: 0000000000000000 R09: 000000000000000c
R10: 0000000000000005 R11: 0000000000000246 R12: 00007fff07ffb100
R13: 0000000003360a60 R14: 0000000000000000 R15: 00000000000d0fcf
Kernel Offset: disabled
Rebooting in 86400 seconds..