WARNING in btrfs_commit_transaction (2)

Status: upstream: reported on 2026/08/31 12:10
Reported-by: syzbot+e707c9861ba275a73c1e@syzkaller.appspotmail.com
First crash: 71d, last: 19h18m
▶ ▼ Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in btrfs_commit_transaction btrfs -1 syz, C inconclusive done 3 1375d 1469d 22/29 fixed on 2023/02/24 13:50
linux-4.19 WARNING in btrfs_commit_transaction (2) -1 1 1432d 1432d 0/1 auto-obsoleted due to no activity on 2023/04/08 10:50
linux-4.14 WARNING in btrfs_commit_transaction btrfs -1 syz, C 2 1351d 1723d 0/1 upstream: reported C repro on 2022/02/21 07:21
linux-6.1 WARNING in btrfs_commit_transaction origin:upstream -1 syz, C error 27 40d 1126d 0/3 upstream: reported C repro on 2023/10/11 08:58
linux-6.6 WARNING in btrfs_commit_transaction -1 13 291d 504d 0/2 auto-obsoleted due to no activity on 2026/05/03 02:57
linux-4.19 WARNING in btrfs_commit_transaction -1 1 2045d 2045d 0/1 auto-closed as invalid on 2021/08/03 10:34
linux-5.15 WARNING in btrfs_commit_transaction origin:lts-only -1 syz, C done 90 6h49m 1303d 0/3 upstream: reported C repro on 2023/04/17 01:21
upstream WARNING in btrfs_commit_transaction (2) prio:low btrfs -1 syz, C done error 1226 9d19h 1314d 0/29 upstream: reported C repro on 2023/04/06 02:24

Sample crash report:
BTRFS info (device loop9): relocating block group 5242880 flags data|metadata
BTRFS warning (device loop9): Skipping commit of aborted transaction.
------------[ cut here ]------------
BTRFS: Transaction aborted (error -28)
WARNING: CPU: 1 PID: 22563 at fs/btrfs/transaction.c:2039 cleanup_transaction fs/btrfs/transaction.c:2039 [inline]
WARNING: CPU: 1 PID: 22563 at fs/btrfs/transaction.c:2039 btrfs_commit_transaction+0x2b36/0x33a0 fs/btrfs/transaction.c:2621
Modules linked in:
CPU: 1 PID: 22563 Comm: syz.9.3441 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
RIP: 0010:cleanup_transaction fs/btrfs/transaction.c:2039 [inline]
RIP: 0010:btrfs_commit_transaction+0x2b36/0x33a0 fs/btrfs/transaction.c:2621
Code: 00 00 00 49 8d 7f e8 e8 e8 2c ac 00 e9 45 db ff ff e8 4e ea 04 fe 48 c7 c7 60 a2 2c 8b 44 8b 74 24 30 44 89 f6 e8 ea 8e ce fd <0f> 0b e9 d3 f9 ff ff 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c 00 d6
RSP: 0018:ffffc9000476f580 EFLAGS: 00010246
RAX: 5da16d5ca3a05400 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc90012077000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000476f850 R08: ffffc9000476f187 R09: 1ffff920008ede30
R10: dffffc0000000000 R11: fffff520008ede31 R12: ffff8880596b4000
R13: dffffc0000000000 R14: 00000000ffffffe4 R15: ffff88801a32b070
FS:  00007f1ee5ba26c0(0000) GS:ffff8880b8d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b350f9ff8 CR3: 0000000030c1c000 CR4: 00000000003506e0
DR0: 0000000000000008 DR1: 0000000000000007 DR2: 0000000000000004
DR3: 0000000000000034 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 prepare_to_relocate+0x392/0x480 fs/btrfs/relocation.c:3633
 relocate_block_group+0x14a/0xd00 fs/btrfs/relocation.c:3658
 btrfs_relocate_block_group+0x734/0xaa0 fs/btrfs/relocation.c:4119
 btrfs_relocate_chunk+0x12a/0x3b0 fs/btrfs/volumes.c:3447
 __btrfs_balance+0x1865/0x21e0 fs/btrfs/volumes.c:4203
 btrfs_balance+0xc57/0x1130 fs/btrfs/volumes.c:4580
 btrfs_ioctl_balance+0x48c/0x710 fs/btrfs/ioctl.c:3652
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1ee4da8f19
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:00007f1ee5ba2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1ee5025fa0 RCX: 00007f1ee4da8f19
RDX: 00002000000059c0 RSI: 00000000c4009420 RDI: 0000000000000004
RBP: 00007f1ee4e37f6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1ee5026038 R14: 00007f1ee5025fa0 R15: 00007ffcdfe74ce8
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/11/10 05:42 linux-6.6.y 5139929c698c 70ec0380 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in btrfs_commit_transaction
2026/10/15 20:37 linux-6.6.y cecd39af8a1a 3f2522c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in btrfs_commit_transaction
2026/08/31 12:09 linux-6.6.y a4a971135a2f 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in btrfs_commit_transaction
* Struck through repros no longer work on HEAD.