syzbot


WARNING in btrfs_chunk_alloc (2)

Status: upstream: reported C repro on 2025/10/24 07:19
Reported-by: syzbot+59b486de080dec668a26@syzkaller.appspotmail.com
First crash: 1d19h, last: 7h01m
Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in btrfs_chunk_alloc -1 6 864d 947d 0/3 auto-obsoleted due to no activity on 2023/09/22 15:34
linux-6.1 WARNING in btrfs_chunk_alloc (2) origin:lts-only -1 C done 55 43d 710d 0/3 upstream: reported C repro on 2023/11/15 16:30
linux-6.1 WARNING in btrfs_chunk_alloc -1 1 942d 942d 0/3 auto-obsoleted due to no activity on 2023/07/26 13:54
upstream WARNING in btrfs_chunk_alloc btrfs -1 C inconclusive done 637 6h25m 1068d 0/29 upstream: reported C repro on 2022/11/22 11:56
linux-6.6 WARNING in btrfs_chunk_alloc -1 1 116d 116d 0/2 auto-obsoleted due to no activity on 2025/10/09 03:44
linux-5.15 WARNING in btrfs_chunk_alloc (2) origin:lts-only -1 C 46 33d 761d 0/3 upstream: reported C repro on 2023/09/25 19:35

Sample crash report:
------------[ cut here ]------------
BTRFS: Transaction aborted (error -28)
WARNING: CPU: 0 PID: 42 at fs/btrfs/block-group.c:3947 do_chunk_alloc fs/btrfs/block-group.c:3947 [inline]
WARNING: CPU: 0 PID: 42 at fs/btrfs/block-group.c:3947 btrfs_chunk_alloc+0xe42/0xfe0 fs/btrfs/block-group.c:4189
Modules linked in:
CPU: 0 PID: 42 Comm: kworker/u4:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound btrfs_async_reclaim_data_space
RIP: 0010:do_chunk_alloc fs/btrfs/block-group.c:3947 [inline]
RIP: 0010:btrfs_chunk_alloc+0xe42/0xfe0 fs/btrfs/block-group.c:4189
Code: c7 40 f7 ee 8a 89 ee e8 4c fc b7 fd 0f 0b 4c 89 fb e9 2f fe ff ff e8 cd 7e ed fd 48 c7 c7 40 f7 ee 8a 44 89 f6 e8 2e fc b7 fd <0f> 0b 4c 89 fb e9 7c fe ff ff e8 af 7e ed fd 48 c7 c7 40 f7 ee 8a
RSP: 0018:ffffc90000b37918 EFLAGS: 00010246
RAX: 7850eb74c2146200 RBX: ffff88805ea44001 RCX: ffff8880192a9e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: 0000000000000000 R08: ffffc90000b37527 R09: 1ffff92000166ea4
R10: dffffc0000000000 R11: fffff52000166ea5 R12: ffff888023a66800
R13: dffffc0000000000 R14: ffffffffffffffe4 R15: ffff88806e308800
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000717000 CR3: 000000000cb30000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 flush_space+0x516/0xd10 fs/btrfs/space-info.c:764
 btrfs_async_reclaim_data_space+0x12a/0x530 fs/btrfs/space-info.c:1283
 process_one_work kernel/workqueue.c:2634 [inline]
 process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/25 16:21 linux-6.6.y 4a243110dc88 c0460fcd .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (clean fs)] ci2-linux-6-6-kasan WARNING in btrfs_chunk_alloc
2025/10/25 19:55 linux-6.6.y 4a243110dc88 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in btrfs_chunk_alloc
2025/10/25 18:52 linux-6.6.y 4a243110dc88 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in btrfs_chunk_alloc
2025/10/25 18:49 linux-6.6.y 4a243110dc88 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in btrfs_chunk_alloc
2025/10/25 18:43 linux-6.6.y 4a243110dc88 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in btrfs_chunk_alloc
2025/10/25 14:29 linux-6.6.y 4a243110dc88 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in btrfs_chunk_alloc
2025/10/25 14:23 linux-6.6.y 4a243110dc88 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in btrfs_chunk_alloc
2025/10/24 07:19 linux-6.6.y 4a243110dc88 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in btrfs_chunk_alloc
* Struck through repros no longer work on HEAD.