BTRFS info (device loop1): has skinny extents
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WARNING: CPU: 1 PID: 21243 at fs/btrfs/volumes.c:1172 close_fs_devices+0x715/0x930 fs/btrfs/volumes.c:1172
Modules linked in:
CPU: 1 PID: 21243 Comm: syz-executor.4 Not tainted 5.9.0-rc6-next-20200924-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:close_fs_devices+0x715/0x930 fs/btrfs/volumes.c:1172
Code: e8 40 bc 4c fe 85 db 0f 85 65 f9 ff ff e8 d3 bf 4c fe 0f 0b e9 59 f9 ff ff e8 c7 bf 4c fe 0f 0b e9 c0 fe ff ff e8 bb bf 4c fe <0f> 0b e9 f9 fe ff ff 48 c7 c7 3c eb b4 8b e8 78 30 8e fe e9 19 f9
RSP: 0018:ffffc90013297758 EFLAGS: 00010212
RAX: 000000000003448b RBX: ffffffffffffffff RCX: ffffc9000cd1b000
RDX: 0000000000040000 RSI: ffffffff832871b5 RDI: 0000000000000007
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffff8880964e4933
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880964e4930
R13: ffff8880964e49ec R14: ffff88808fbfd908 R15: ffff8880964e4850
FS:  00007f74ed202700(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2b44201000 CR3: 00000000944b7000 CR4: 00000000001506e0
Call Trace:
 btrfs_close_devices+0x8e/0x4b0 fs/btrfs/volumes.c:1184
 open_ctree+0x41cf/0x4274 fs/btrfs/disk-io.c:3398
 btrfs_fill_super fs/btrfs/super.c:1315 [inline]
 btrfs_mount_root.cold+0x14/0x165 fs/btrfs/super.c:1671
 legacy_get_tree+0x105/0x220 fs/fs_context.c:592
 vfs_get_tree+0x89/0x2f0 fs/super.c:1547
 fc_mount fs/namespace.c:983 [inline]
 vfs_kern_mount.part.0+0xd3/0x170 fs/namespace.c:1013
 vfs_kern_mount+0x3c/0x60 fs/namespace.c:1000
 btrfs_mount+0x234/0xa60 fs/btrfs/super.c:1731
 legacy_get_tree+0x105/0x220 fs/fs_context.c:592
 vfs_get_tree+0x89/0x2f0 fs/super.c:1547
 do_new_mount fs/namespace.c:2896 [inline]
 path_mount+0x12ae/0x1e70 fs/namespace.c:3227
 __do_sys_mount fs/namespace.c:3438 [inline]
 __se_sys_mount fs/namespace.c:3411 [inline]
 __x64_sys_mount+0x278/0x2f0 fs/namespace.c:3411
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x460bca
Code: b8 a6 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 dd 87 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 ba 87 fb ff c3 66 0f 1f 84 00 00 00 00 00
RSP: 002b:00007f74ed201a88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f74ed201b20 RCX: 0000000000460bca
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f74ed201ae0
RBP: 00007f74ed201ae0 R08: 00007f74ed201b20 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000
R13: 0000000020000100 R14: 0000000020000200 R15: 0000000020000040