WARNING in btrfs_commit_transaction

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: a35d65bedfbc Linux 4.14.267
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13fd16fa700000
kernel config: https://syzkaller.appspot.com/x/.config?x=8535d773e783c59a
dashboard link: https://syzkaller.appspot.com/bug?extid=8e8818a1efc5f1b96f96
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=170dcba4700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14be09ca700000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8e8818...@syzkaller.appspotmail.com

should_failslab+0xd6/0x130 mm/failslab.c:32
slab_pre_alloc_hook mm/slab.h:421 [inline]
slab_alloc mm/slab.c:3376 [inline]
kmem_cache_alloc+0x40/0x3c0 mm/slab.c:3550
mempool_alloc+0x10e/0x2d0 mm/mempool.c:330
------------[ cut here ]------------
bio_alloc_bioset+0x41b/0x830 block/bio.c:486
WARNING: CPU: 0 PID: 13000 at fs/btrfs/transaction.c:1883 cleanup_transaction.cold+0x14/0x7ab fs/btrfs/transaction.c:1883
Kernel panic - not syncing: panic_on_warn set ...

bio_alloc include/linux/bio.h:422 [inline]
blkdev_issue_flush+0xeb/0x320 block/blk-flush.c:527
ext4_sync_fs+0x46f/0x7e0 fs/ext4/super.c:5066
sync_fs_one_sb fs/sync.c:80 [inline]
sync_fs_one_sb+0xb1/0xe0 fs/sync.c:77
iterate_supers+0x124/0x490 fs/super.c:613
sys_sync+0x9a/0x130 fs/sync.c:115
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f3c6be997c9
RSP: 002b:00007fffd4e68c18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f3c6be997c9
RDX: 0000000000000c20 RSI: 000000000000fefe RDI: 00007fffd4e68c20
RBP: 00007fffd4e68c20 R08: 0000000000000001 R09: 0000000000000034
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fffd4e68cc0 R14: 00007fffd4e68c80 R15: 0000000000000066
CPU: 0 PID: 13000 Comm: syz-executor793 Not tainted 4.14.267-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x281 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
__warn.cold+0x20/0x44 kernel/panic.c:547
report_bug+0x208/0x250 lib/bug.c:183
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:cleanup_transaction.cold+0x14/0x7ab fs/btrfs/transaction.c:1883
RSP: 0018:ffff88809ee7fb98 EFLAGS: 00010286
RAX: 0000000000000026 RBX: ffff8880b50bed80 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff878bbcc0 RDI: ffffed1013dcff69
RBP: ffff88808bf9ba10 R08: 0000000000000026 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff11013dcff7a
R13: 00000000fffffff4 R14: ffff88808bf9ba70 R15: ffff88808bf9ba40
btrfs_commit_transaction+0x1735/0x2210 fs/btrfs/transaction.c:2341
btrfs_sync_fs+0xe9/0x430 fs/btrfs/super.c:1217
sync_fs_one_sb fs/sync.c:80 [inline]
sync_fs_one_sb+0xb1/0xe0 fs/sync.c:77
iterate_supers+0x124/0x490 fs/super.c:613
sys_sync+0x9a/0x130 fs/sync.c:115
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f3c6be997c9
RSP: 002b:00007fffd4e68c18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f3c6be997c9
RDX: 0000000000000c20 RSI: 000000000000fefe RDI: 00007fffd4e68c20
RBP: 00007fffd4e68c20 R08: 0000000000000001 R09: 0000000000000034
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fffd4e68cc0 R14: 00007fffd4e68c80 R15: 0000000000000061
Kernel Offset: disabled
Rebooting in 86400 seconds..


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