loop0: detected capacity change from 0 to 32768
BTRFS: device fsid 395ef67a-297e-477c-816d-cd80a5b93e5d devid 1 transid 8 /dev/loop0 (7:0) scanned by syz.0.0 (5314)
BTRFS info (device loop0): first mount of filesystem 395ef67a-297e-477c-816d-cd80a5b93e5d
BTRFS info (device loop0): using sha256 checksum algorithm
BTRFS info (device loop0): enabling ssd optimizations
BTRFS info (device loop0): turning on async discard
BTRFS info (device loop0): enabling free space tree
------------[ cut here ]------------
ret
WARNING: fs/btrfs/extent-tree.c:837 at lookup_inline_extent_backref+0x143e/0x1980 fs/btrfs/extent-tree.c:837, CPU#0: syz.0.0/5314
Modules linked in:
CPU: 0 UID: 0 PID: 5314 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:lookup_inline_extent_backref+0x143e/0x1980 fs/btrfs/extent-tree.c:837
Code: d8 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 58 53 c4 07 cc e8 a2 66 e5 fd bb fe ff ff ff 4c 8b 74 24 50 e9 af fe ff ff 90 <0f> 0b 90 48 8b 84 24 88 00 00 00 48 b9 00 00 00 00 00 fc ff df 80
RSP: 0018:ffffc9000fb6edc0 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000002
RDX: ffff8880367b4900 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000fb6efe8 R08: 0000000000000000 R09: 1ffffd4000095338
R10: dffffc0000000000 R11: fffff94000095339 R12: 0000000000510000
R13: ffff888012682840 R14: 0000000000000009 R15: ffff888036c34000
FS:  00007f0f546a06c0(0000) GS:ffff88808caa3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000336e7000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 insert_inline_extent_backref+0xa8/0x300 fs/btrfs/extent-tree.c:1206
 __btrfs_inc_extent_ref+0x271/0xa00 fs/btrfs/extent-tree.c:1505
 run_delayed_tree_ref fs/btrfs/extent-tree.c:1771 [inline]
 run_one_delayed_ref fs/btrfs/extent-tree.c:1803 [inline]
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:2003 [inline]
 __btrfs_run_delayed_refs+0xf82/0x4170 fs/btrfs/extent-tree.c:2078
 btrfs_run_delayed_refs+0x191/0x3b0 fs/btrfs/extent-tree.c:2190
 qgroup_account_snapshot fs/btrfs/transaction.c:1589 [inline]
 create_pending_snapshot+0x1141/0x3ac0 fs/btrfs/transaction.c:1872
 create_pending_snapshots+0x17c/0x1c0 fs/btrfs/transaction.c:1942
 btrfs_commit_transaction+0xf75/0x31a0 fs/btrfs/transaction.c:2439
 create_snapshot fs/btrfs/ioctl.c:779 [inline]
 btrfs_mksubvol+0x9bc/0x10a0 fs/btrfs/ioctl.c:857
 btrfs_mksnapshot+0xab/0xf0 fs/btrfs/ioctl.c:899
 __btrfs_ioctl_snap_create+0x52e/0x750 fs/btrfs/ioctl.c:1163
 btrfs_ioctl_snap_create_v2+0x1f8/0x3b0 fs/btrfs/ioctl.c:1242
 btrfs_ioctl+0xa62/0xd00 fs/btrfs/ioctl.c:-1
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0f5379bf79
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0f546a0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f0f53a15fa0 RCX: 00007f0f5379bf79
RDX: 0000200000001480 RSI: 0000000050009417 RDI: 0000000000000006
RBP: 00007f0f538327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0f53a16038 R14: 00007f0f53a15fa0 R15: 00007ffd0b8a9258
 </TASK>