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INFO: rcu detected stall in batadv_nc_worker

Status: upstream: reported C repro on 2023/06/13 20:27
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+42b636738d776704a740@syzkaller.appspotmail.com
First crash: 923d, last: 2d10h
Fix commit to backport (bisect log) :
tree: upstream
commit 5f6bd380c7bdbe10f7b4e8ddcceed60ce0714c6d
Author: Peter Zijlstra <peterz@infradead.org>
Date: Mon May 27 12:06:55 2024 +0000

  sched/rt: Remove default bandwidth control

  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/03/16 linux-5.15.y (ToT) 0c935c049b5c C [report] INFO: rcu detected stall in corrupted
2025/03/16 upstream (ToT) 31d7109a19f6 C Didn't crash
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in batadv_nc_worker origin:lts-only 1 C done 220 2d15h 900d 0/3 upstream: reported C repro on 2023/07/06 06:16
upstream INFO: rcu detected stall in batadv_nc_worker cgroups mm 1 7 2210d 2211d 0/29 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in batadv_nc_worker (2) mm 1 4 2175d 2175d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in batadv_nc_worker (3) batman 1 C done inconclusive 585 97d 1908d 0/29 upstream: reported C repro on 2020/10/01 10:35
▶ ▼ Fix bisection attempts (1)
Created Duration User Patch Repo Result
2025/07/31 07:51 7h53m fix candidate upstream OK (1) job log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4384/1:b..l
	(detected by 1, t=10502 jiffies, g=6225, q=362)
task:kworker/u4:6    state:R  running task     stack:26368 pid: 4384 ppid:     2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6799
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x1f2/0x3f0 kernel/locking/lockdep.c:5627
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f6 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc90003bafa40 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 7cf000ba9edd0b00
RDX: 0000000000000000 RSI: ffffffff8a0b2f00 RDI: ffffffff8a59e580
RBP: ffffc90003bafb58 R08: dffffc0000000000 R09: fffffbfff1ff7c19
R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: ffffffff8c11c760
R13: 1ffff92000775f54 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
 rcu_read_lock include/linux/rcupdate.h:740 [inline]
 batadv_nc_process_nc_paths+0xb2/0x350 net/batman-adv/network-coding.c:691
 batadv_nc_worker+0x3e5/0x5c0 net/batman-adv/network-coding.c:732
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread starved for 10531 jiffies! g6225 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27008 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11bb/0x4390 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4412 Comm: syz.2.19 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4700 [inline]
RIP: 0010:__lock_acquire+0x6a3/0x7c60 kernel/locking/lockdep.c:4962
Code: 00 48 8b 84 24 88 00 00 00 42 0f b6 04 00 84 c0 0f 85 69 63 00 00 45 8b bd e8 0a 00 00 41 8d 47 ff 83 f8 ff 41 bc ff ff ff ff <44> 0f 4c e0 49 81 c5 10 0b 00 00 41 ff c4 45 8d 77 01 49 ff cf 44
RSP: 0018:ffffc90003c8f8a0 EFLAGS: 00000046
RAX: 00000000ffffffff RBX: 0000000000000000 RCX: 0000000000000003
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffbe0f0
RBP: ffffc90003c8faf0 R08: dffffc0000000000 R09: fffffbfff1ff7c1f
R10: fffffbfff1ff7c1f R11: 1ffffffff1ff7c1e R12: 00000000ffffffff
R13: ffff88802040d940 R14: 0000000000000003 R15: 0000000000000000
FS:  00005555722b3500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 000000001f980000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 __might_fault+0xb3/0x110 mm/memory.c:5357
 __clear_user arch/x86/lib/usercopy_64.c:20 [inline]
 clear_user+0xd2/0x150 arch/x86/lib/usercopy_64.c:54
 copy_siginfo_to_user+0x57/0x80 kernel/signal.c:3369
 __setup_rt_frame arch/x86/kernel/signal.c:490 [inline]
 setup_rt_frame arch/x86/kernel/signal.c:780 [inline]
 handle_signal arch/x86/kernel/signal.c:824 [inline]
 arch_do_signal_or_restart+0xd56/0x1300 arch/x86/kernel/signal.c:869
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6f14ba3749
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff064bace8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f6f14df9fa0 RCX: 00007f6f14ba3749
RDX: 000020000006b000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f6f14c27f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6f14df9fa0 R14: 00007f6f14df9fa0 R15: 0000000000000004
 </TASK>

Crashes (300):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/30 14:16 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/24 23:17 linux-5.15.y ac56c046adf4 c0460fcd .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/09/30 01:32 linux-5.15.y 43bb85222e53 86341da6 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/09/19 16:25 linux-5.15.y 43bb85222e53 67c37560 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in batadv_nc_worker
2025/08/31 02:37 linux-5.15.y 01879f56bdde 807a3b61 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/08/30 15:04 linux-5.15.y 01879f56bdde 807a3b61 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/02/13 09:32 linux-5.15.y c16c81c81336 b27c2402 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/12/13 18:28 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/12/10 10:28 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/09/09 09:14 linux-5.15.y 7a6c2d093c45 d291dd2d .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/12/20 11:55 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/12/19 02:16 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/12/17 15:01 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/12/16 03:21 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in batadv_nc_worker
2025/12/12 23:08 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/12/09 20:35 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/12/07 10:36 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/12/02 04:02 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/12/01 11:52 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/28 17:52 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/28 10:12 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/24 22:09 linux-5.15.y cc5ec8769306 bf6fe8fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/24 08:12 linux-5.15.y cc5ec8769306 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/21 04:44 linux-5.15.y cc5ec8769306 2cc4c24a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/20 18:46 linux-5.15.y cc5ec8769306 2cc4c24a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/20 06:37 linux-5.15.y cc5ec8769306 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/18 06:24 linux-5.15.y cc5ec8769306 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/17 17:57 linux-5.15.y cc5ec8769306 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/13 21:47 linux-5.15.y cc5ec8769306 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/07 17:36 linux-5.15.y cc5ec8769306 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/06 08:54 linux-5.15.y cc5ec8769306 a6c9c731 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/06 03:14 linux-5.15.y cc5ec8769306 a6c9c731 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/04 21:12 linux-5.15.y cc5ec8769306 686bf657 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/04 07:12 linux-5.15.y cc5ec8769306 686bf657 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/04 02:16 linux-5.15.y cc5ec8769306 686bf657 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/11/02 17:21 linux-5.15.y cc5ec8769306 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/30 07:40 linux-5.15.y cc5ec8769306 fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/27 00:40 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/26 14:23 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/26 09:29 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in batadv_nc_worker
2025/10/25 07:43 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in batadv_nc_worker
2025/10/24 16:10 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/24 09:21 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/21 11:04 linux-5.15.y ac56c046adf4 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/19 10:52 linux-5.15.y 29e53a5b1c4f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/18 06:26 linux-5.15.y 29e53a5b1c4f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/18 02:39 linux-5.15.y 29e53a5b1c4f 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/15 21:50 linux-5.15.y 29e53a5b1c4f 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/11 16:44 linux-5.15.y 29e53a5b1c4f ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/11 11:30 linux-5.15.y 29e53a5b1c4f ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/08 10:49 linux-5.15.y 29e53a5b1c4f 7e2882b3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/04 21:09 linux-5.15.y 29e53a5b1c4f 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/10/02 20:04 linux-5.15.y 29e53a5b1c4f 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/09/29 19:34 linux-5.15.y 43bb85222e53 86341da6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/09/25 09:32 linux-5.15.y 43bb85222e53 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/09/24 19:44 linux-5.15.y 43bb85222e53 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/09/24 04:29 linux-5.15.y 43bb85222e53 e667a34f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/09/23 00:11 linux-5.15.y 43bb85222e53 0ac7291c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/09/18 23:08 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2025/09/13 15:28 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2024/05/18 17:45 linux-5.15.y 83655231580b c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in batadv_nc_worker
2023/06/13 20:26 linux-5.15.y 7349e40704a0 d2ee9228 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
* Struck through repros no longer work on HEAD.