WARNING in btrfs_run_delayed_refs

Status: upstream: reported C repro on 2023/04/02 18:59
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+7e32a3da87c746be16c0@syzkaller.appspotmail.com
First crash: 1229d, last: 16d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2023/05/16 linux-5.15.y (ToT) b0ece631f84a C [report] WARNING in btrfs_run_delayed_refs
2023/05/16 upstream (ToT) f1fcbaa18b28 C Didn't crash
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 WARNING in btrfs_run_delayed_refs btrfs -1 syz, C error 9 1262d 1641d 0/1 upstream: reported C repro on 2022/02/14 22:12
upstream WARNING in btrfs_run_delayed_refs (2) prio:high btrfs -1 syz, C done error 189 7d03h 1149d 0/29 upstream: reported C repro on 2023/06/22 14:13
linux-6.1 WARNING in btrfs_run_delayed_refs -1 1 588d 588d 0/3 auto-obsoleted due to no activity on 2025/04/13 14:47
linux-6.1 WARNING in btrfs_run_delayed_refs (2) -1 1 448d 448d 0/3 auto-obsoleted due to no activity on 2025/08/31 03:17
upstream WARNING in btrfs_run_delayed_refs btrfs -1 syz, C error done 15 1284d 1397d 22/29 fixed on 2023/03/15 11:57
linux-4.14 WARNING in btrfs_run_delayed_refs btrfs -1 syz, C 1 1283d 1283d 0/1 upstream: reported C repro on 2023/02/08 10:50
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/07/20 19:06 21m retest repro linux-5.15.y report log
2026/07/20 19:06 18m retest repro linux-5.15.y report log
2026/07/20 19:06 20m retest repro linux-5.15.y report log
2026/07/20 19:06 16m retest repro linux-5.15.y report log
2026/05/05 12:18 15m retest repro linux-5.15.y error
2026/05/05 12:18 16m retest repro linux-5.15.y report log
2026/05/05 12:18 24m retest repro linux-5.15.y report log
2026/05/05 12:18 39m retest repro linux-5.15.y report log
2026/02/22 20:22 42m retest repro linux-5.15.y report log
2026/02/22 20:22 45m retest repro linux-5.15.y report log
▶ ▼ Fix bisection attempts (14)
Created Duration User Patch Repo Result
2026/03/25 07:32 1m fix candidate upstream error job log
2026/02/23 00:44 0m fix candidate upstream error job log
2026/01/23 12:05 0m fix candidate upstream error job log
2025/12/19 13:44 3m fix candidate upstream error job log
2024/12/22 14:10 6m fix candidate upstream error job log
2024/10/15 03:51 0m fix candidate upstream error job log
2024/09/02 05:13 3m fix candidate upstream error job log
2024/07/09 05:48 1m fix candidate upstream error job log
2024/03/08 00:14 0m fix candidate upstream error job log
2024/02/02 20:08 0m fix candidate upstream error job log
2023/12/17 13:53 1m fix candidate upstream error job log
2023/11/16 03:03 1m fix candidate upstream error job log
2023/10/11 17:05 0m fix candidate upstream error job log
2023/10/07 10:15 0m bisect fix linux-5.15.y error job log

Sample crash report:
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
BTRFS error (device loop0): failed to run delayed ref for logical 5255168 num_bytes 4096 type 176 action 2 ref_mod 1: -12
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4021 at fs/btrfs/extent-tree.c:2158 btrfs_run_delayed_refs+0x408/0x47c fs/btrfs/extent-tree.c:2158
Modules linked in:
CPU: 0 PID: 4021 Comm: syz-executor900 Not tainted 5.15.176-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : btrfs_run_delayed_refs+0x408/0x47c fs/btrfs/extent-tree.c:2158
lr : btrfs_run_delayed_refs+0x408/0x47c fs/btrfs/extent-tree.c:2158
sp : ffff80001fb177b0
x29: ffff80001fb177c0 x28: dfff800000000000 x27: ffff0000d1e1f024
x26: 00000000fffffff4 x25: ffff0000dbfaf1b8 x24: 1fffe0001b7f5e37
x23: ffff0000dbfaf1b8 x22: 0000000000000000 x21: 0000000000000006
x20: ffff0000d1e1f000 x19: ffff0000dbfaf160 x18: 0000000000000001
x17: 0000000000000000 x16: ffff800011b4c240 x15: 00000000ffffffff
x14: ffff0000dce8d1c0 x13: 0000000000000001 x12: 0000000000000001
x11: 0000000000000000 x10: 0000000000000000 x9 : b95b5cd9c334b500
x8 : b95b5cd9c334b500 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff80001fb16f18 x4 : ffff800014c40660 x3 : ffff8000085567f8
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000026
Call trace:
 btrfs_run_delayed_refs+0x408/0x47c fs/btrfs/extent-tree.c:2158
 btrfs_commit_transaction+0x1b8/0x30f0 fs/btrfs/transaction.c:2166
 btrfs_ioctl_set_fslabel+0x2e8/0x39c fs/btrfs/ioctl.c:4706
 btrfs_ioctl+0x50c/0xa5c fs/btrfs/ioctl.c:4933
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
irq event stamp: 86880
hardirqs last  enabled at (86879): [<ffff80000832c1a4>] __up_console_sem+0xb4/0x100 kernel/printk/printk.c:257
hardirqs last disabled at (86880): [<ffff800011b478f4>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:396
softirqs last  enabled at (86868): [<ffff8000081b691c>] softirq_handle_end kernel/softirq.c:401 [inline]
softirqs last  enabled at (86868): [<ffff8000081b691c>] handle_softirqs+0xb88/0xdbc kernel/softirq.c:586
softirqs last disabled at (86837): [<ffff8000081b6fb4>] __do_softirq kernel/softirq.c:592 [inline]
softirqs last disabled at (86837): [<ffff8000081b6fb4>] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline]
softirqs last disabled at (86837): [<ffff8000081b6fb4>] invoke_softirq kernel/softirq.c:439 [inline]
softirqs last disabled at (86837): [<ffff8000081b6fb4>] __irq_exit_rcu+0x268/0x4d8 kernel/softirq.c:641
---[ end trace fe84c1a861b679c8 ]---
BTRFS: error (device loop0) in btrfs_run_delayed_refs:2158: errno=-12 Out of memory
BTRFS info (device loop0): forced readonly

Crashes (26):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/23 08:14 linux-5.15.y 4735586da88e a44b0418 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2024/08/24 20:04 linux-5.15.y fa93fa65db6e d7d32352 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2024/01/21 19:02 linux-5.15.y ddcaf4999061 9bd8dcda .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2023/04/02 19:34 linux-5.15.y c957cbb87315 f325deb0 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2026/07/28 21:33 linux-5.15.y 674f684f7c61 edc8a875 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in btrfs_run_delayed_refs
2025/11/17 02:46 linux-5.15.y cc5ec8769306 f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in btrfs_run_delayed_refs
2025/10/25 04:46 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in btrfs_run_delayed_refs
2025/02/19 01:18 linux-5.15.y c16c81c81336 9a14138f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in btrfs_run_delayed_refs
2025/02/15 08:51 linux-5.15.y c16c81c81336 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in btrfs_run_delayed_refs
2025/04/29 06:58 linux-5.15.y f7347f400572 aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2025/04/24 07:50 linux-5.15.y f7347f400572 9882047a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2025/04/14 23:39 linux-5.15.y f7347f400572 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2025/03/16 06:39 linux-5.15.y 0c935c049b5c e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2025/01/23 07:44 linux-5.15.y 4735586da88e a44b0418 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2024/08/24 19:16 linux-5.15.y fa93fa65db6e d7d32352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2024/07/26 15:12 linux-5.15.y 7c6d66f0266f 3f86dfed .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2024/01/21 18:34 linux-5.15.y ddcaf4999061 9bd8dcda .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2023/07/16 22:59 linux-5.15.y d54cfc420586 35d9ecc5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in btrfs_run_delayed_refs
2023/08/14 04:40 linux-5.15.y 24c4de4069cb 39990d51 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2023/07/09 10:09 linux-5.15.y d54cfc420586 668cb1fa .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2023/07/08 12:33 linux-5.15.y d54cfc420586 668cb1fa .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2023/06/23 12:15 linux-5.15.y f67653019430 79782afc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2023/06/02 19:03 linux-5.15.y 0ab06468cbd1 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2023/04/27 20:04 linux-5.15.y f48aeeaaa64c 6f3d6fa7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2023/04/08 23:51 linux-5.15.y d86dfc4d95cd 71147e29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
2023/04/02 18:59 linux-5.15.y c957cbb87315 f325deb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in btrfs_run_delayed_refs
* Struck through repros no longer work on HEAD.