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kernel BUG at fs/btrfs/volumes.c:891!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 2318 Comm: syz-executor.5 Not tainted 4.14.213-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88809c82c1c0 task.stack: ffff88805a158000
RIP: 0010:btrfs_prepare_close_one_device fs/btrfs/volumes.c:891 [inline]
RIP: 0010:__btrfs_close_devices+0x86d/0xb20 fs/btrfs/volumes.c:916
RSP: 0018:ffff88805a15f820 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff8880a622fb40 RCX: ffffc900132ed000
RDX: 0000000000040000 RSI: ffffffff82ad702d RDI: 0000000000000286
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888099b9ac80
R13: ffff8880a622fc08 R14: fffffffffffffff4 R15: ffff88809b286d80
FS:  00007fe27cb50700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561d45421000 CR3: 0000000065d09000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 btrfs_close_devices+0x24/0x140 fs/btrfs/volumes.c:949
 btrfs_mount+0x1686/0x1fe0 fs/btrfs/super.c:1648
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
 vfs_kern_mount+0x3c/0x60 fs/namespace.c:1036
 mount_subvol fs/btrfs/super.c:1398 [inline]
 btrfs_mount+0x42a/0x1fe0 fs/btrfs/super.c:1569
 mount_fs+0x92/0x2a0 fs/super.c:1237
 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2549 [inline]
 do_mount+0xe53/0x2a00 fs/namespace.c:2879
 SYSC_mount fs/namespace.c:3095 [inline]
 SyS_mount+0xa8/0x120 fs/namespace.c:3072
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x460c6a
RSP: 002b:00007fe27cb4fa78 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fe27cb4fb10 RCX: 0000000000460c6a
RDX: 0000000020000000 RSI: 0000000020000040 RDI: 00007fe27cb4fad0
RBP: 00007fe27cb4fad0 R08: 00007fe27cb4fb10 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000
R13: 0000000020000040 R14: 0000000020000200 R15: 00000000200007c0
Code: ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e f0 01 00 00 48 8b 44 24 08 c7 80 10 01 00 00 00 00 00 00 e9 4f f8 ff ff e8 73 cf a9 fe <0f> 0b e8 6c cf a9 fe 0f 0b 48 89 cf e8 52 9f d3 fe e9 19 f8 ff 
RIP: btrfs_prepare_close_one_device fs/btrfs/volumes.c:891 [inline] RSP: ffff88805a15f820
RIP: __btrfs_close_devices+0x86d/0xb20 fs/btrfs/volumes.c:916 RSP: ffff88805a15f820
---[ end trace d3fbe2c492f13e48 ]---