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BTRFS: Transaction aborted (error -28)
WARNING: fs/btrfs/block-group.c:4012 at do_chunk_alloc fs/btrfs/block-group.c:4012 [inline], CPU#0: syz.0.0/5339
WARNING: fs/btrfs/block-group.c:4012 at btrfs_chunk_alloc+0x101d/0x15d0 fs/btrfs/block-group.c:4253, CPU#0: syz.0.0/5339
Modules linked in:
CPU: 0 UID: 0 PID: 5339 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:do_chunk_alloc fs/btrfs/block-group.c:4012 [inline]
RIP: 0010:btrfs_chunk_alloc+0x101f/0x15d0 fs/btrfs/block-group.c:4253
Code: b7 de c1 fd e9 6d 01 00 00 e8 0d 8d a7 fd 84 c0 74 22 e8 a4 de c1 fd e9 5a 01 00 00 e8 9a de c1 fd 48 8d 3d 33 85 d7 0b 89 de <67> 48 0f b9 3a e9 b3 fc ff ff e8 b2 da 79 07 41 89 c6 31 ff 89 c6
RSP: 0018:ffffc9000bb773d8 EFLAGS: 00010283
RAX: ffffffff8400c9c6 RBX: ffffffffffffffe4 RCX: 0000000000100000
RDX: ffffc900218c3000 RSI: 00000000ffffffe4 RDI: ffffffff8fd84f00
RBP: 0000000000000000 R08: ffff88800036c980 R09: 0000000000000003
R10: 00000000fffffffb R11: 0000000000000002 R12: 1ffff110080bc616
R13: ffff8880470cd500 R14: ffff888042170001 R15: ffff88804214d000
FS:  00007f34824366c0(0000) GS:ffff88808cf1d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffce6ce8df0 CR3: 000000004391d000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 find_free_extent_update_loop fs/btrfs/extent-tree.c:4199 [inline]
 find_free_extent+0x45c3/0x5d00 fs/btrfs/extent-tree.c:4611
 btrfs_reserve_extent+0x30e/0x7f0 fs/btrfs/extent-tree.c:4705
 __btrfs_prealloc_file_range+0x2c1/0xd90 fs/btrfs/inode.c:9141
 btrfs_prealloc_file_range+0x40/0x60 fs/btrfs/inode.c:9234
 btrfs_fallocate+0x14ba/0x1c40 fs/btrfs/file.c:3250
 vfs_fallocate+0x669/0x7e0 fs/open.c:339
 ksys_fallocate fs/open.c:363 [inline]
 __do_sys_fallocate fs/open.c:368 [inline]
 __se_sys_fallocate fs/open.c:366 [inline]
 __x64_sys_fallocate+0xc0/0x110 fs/open.c:366
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f348159acb9
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:00007f3482436028 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f3481816090 RCX: 00007f348159acb9
RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 00007f3481608bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000000f4 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3481816128 R14: 00007f3481816090 R15: 00007ffe9cd76328
 </TASK>
----------------
Code disassembly (best guess):
   0:	b7 de                	mov    $0xde,%bh
   2:	c1 fd e9             	sar    $0xe9,%ebp
   5:	6d                   	insl   (%dx),%es:(%rdi)
   6:	01 00                	add    %eax,(%rax)
   8:	00 e8                	add    %ch,%al
   a:	0d 8d a7 fd 84       	or     $0x84fda78d,%eax
   f:	c0 74 22 e8 a4       	shlb   $0xa4,-0x18(%rdx,%riz,1)
  14:	de c1                	faddp  %st,%st(1)
  16:	fd                   	std
  17:	e9 5a 01 00 00       	jmp    0x176
  1c:	e8 9a de c1 fd       	call   0xfdc1debb
  21:	48 8d 3d 33 85 d7 0b 	lea    0xbd78533(%rip),%rdi        # 0xbd7855b
  28:	89 de                	mov    %ebx,%esi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	e9 b3 fc ff ff       	jmp    0xfffffce7
  34:	e8 b2 da 79 07       	call   0x779daeb
  39:	41 89 c6             	mov    %eax,%r14d
  3c:	31 ff                	xor    %edi,%edi
  3e:	89 c6                	mov    %eax,%esi