WARNING in btrfs_run_delayed_refs

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=124686f8700000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=4b2b69a259af6f44dc9e
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1449ab9c700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1425305a700000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4b2b69...@syzkaller.appspotmail.com

fail_dump lib/fault-inject.c:51 [inline]
should_fail.cold+0xa/0xf lib/fault-inject.c:149
__should_failslab+0x115/0x180 mm/failslab.c:32
should_failslab+0x5/0x10 mm/slab_common.c:1590
slab_pre_alloc_hook mm/slab.h:424 [inline]
slab_alloc mm/slab.c:3383 [inline]
kmem_cache_alloc+0x277/0x370 mm/slab.c:3557
kmem_cache_zalloc include/linux/slab.h:699 [inline]
start_transaction+0x2cd/0xf90 fs/btrfs/transaction.c:511
WARNING: CPU: 1 PID: 8174 at fs/btrfs/extent-tree.c:2938 btrfs_run_delayed_refs.part.0+0x2b7/0x310 fs/btrfs/extent-tree.c:2938
btrfs_attach_transaction_barrier+0x22/0x80 fs/btrfs/transaction.c:704
Kernel panic - not syncing: panic_on_warn set ...

btrfs_sync_fs+0xf4/0x490 fs/btrfs/super.c:1254
sync_fs_one_sb fs/sync.c:80 [inline]
sync_fs_one_sb+0xbe/0xf0 fs/sync.c:77
iterate_supers+0x13c/0x290 fs/super.c:633
ksys_sync+0xa8/0x150 fs/sync.c:115
__ia32_sys_sync+0xa/0x10 fs/sync.c:124
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f5468950019
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc17e619a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5468950019
RDX: 00000000000009c0 RSI: 000000000000fbfe RDI: 00007ffc17e619c0
RBP: 00007ffc17e619c0 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007ffc17e619e0 R14: 00007ffc17e619bc R15: 00007ffc17e619d0
CPU: 1 PID: 8174 Comm: syz-executor692 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
BTRFS warning (device <unknown>): duplicate device /dev/loop3 devid 1 generation 7 scanned by syz-executor692 (8157)
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
panic+0x26a/0x50e kernel/panic.c:186
cifs_request 67KB 67KB
cifs_mpx_ids 0KB 7KB
nfs_commit_data 3KB 14KB
nfs_write_data 34KB 44KB
ext4_system_zone 1KB 7KB
bio-1 1KB 7KB
__warn.cold+0x20/0x5a kernel/panic.c:541
rpc_buffers 17KB 25KB
rpc_tasks 2KB 7KB
report_bug+0x262/0x2b0 lib/bug.c:183
UNIX 420KB 420KB
fixup_bug arch/x86/kernel/traps.c:178 [inline]
fixup_bug arch/x86/kernel/traps.c:173 [inline]
do_error_trap+0x1d7/0x310 arch/x86/kernel/traps.c:296
tcp_bind_bucket 0KB 4KB
ip_fib_trie 0KB 3KB
ip_fib_alias 0KB 3KB
invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038
RIP: 0010:btrfs_run_delayed_refs.part.0+0x2b7/0x310 fs/btrfs/extent-tree.c:2938
Code: 89 e6 bf fb ff ff ff e8 37 f1 7e fe 41 83 fc fb 0f 84 e7 8a 16 05 e8 b8 ef 7e fe 44 89 e6 48 c7 c7 40 23 a4 88 e8 8e 27 0f 05 <0f> 0b e8 a2 ef 7e fe 44 89 e1 ba 7a 0b 00 00 48 89 ef 48 c7 c6 80
RSP: 0018:ffff888095267c40 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff814dff01 RDI: ffffed1012a4cf7a
ip_dst_cache 3KB 8KB
RBP: ffff88808dbab738 R08: 0000000000000001 R09: 0000000000000000
RAW 6KB 15KB
R10: 0000000000000005 R11: 0000000000000000 R12: 00000000fffffff4
UDP 25KB 40KB
R13: ffff88808dbab788 R14: ffff888096da2900 R15: 0000000000000008
tw_sock_TCP 0KB 3KB
btrfs_run_delayed_refs+0xad/0xf0 fs/btrfs/extent-tree.c:2925
btrfs_commit_transaction+0x173/0x2480 fs/btrfs/transaction.c:1972
btrfs_sync_fs+0x120/0x490 fs/btrfs/super.c:1279
request_sock_TCP 1KB 7KB
TCP 5KB 5KB
sync_fs_one_sb fs/sync.c:80 [inline]
sync_fs_one_sb+0xbe/0xf0 fs/sync.c:77
hugetlbfs_inode_cache 3KB 15KB
iterate_supers+0x13c/0x290 fs/super.c:633
ksys_sync+0xa8/0x150 fs/sync.c:115
fscache_cookie_jar 1KB 7KB
__ia32_sys_sync+0xa/0x10 fs/sync.c:124
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f5468950019
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc17e619a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5468950019
RDX: 00000000000009c0 RSI: 000000000000fbfe RDI: 00007ffc17e619c0
RBP: 00007ffc17e619c0 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
eventpoll_pwq 52KB 95KB
R13: 00007ffc17e619e0 R14: 00007ffc17e619bc R15: 00007ffc17e619d0
Kernel Offset: disabled
Rebooting in 86400 seconds..


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