rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P404/1:b..l
(detected by 1, t=10502 jiffies, g=12709, q=221)
task:kworker/u4:3 state:R running task stack:21352 pid: 404 ppid: 2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
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_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681
RIP: 0010:batadv_nc_process_nc_paths+0x14f/0x350 net/batman-adv/network-coding.c:692
Code: 1f 8b e8 e4 ab 1f 00 4c 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 ef e8 95 58 3d f8 4d 8b 6d 00 <4d> 85 ed 75 0f e8 77 f0 f8 f7 e9 c4 00 00 00 e8 6d f0 f8 f7 49 8d
RSP: 0018:ffffc9000307fb78 EFLAGS: 00000246
RAX: 1ffff110290e0560 RBX: ffffffff897edbd0 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff8a59a4a0 RDI: ffffffff8a59a460
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1ff7a19
R10: fffffbfff1ff7a19 R11: 1ffffffff1ff7a18 R12: ffff88801b5890d0
R13: 0000000000000000 R14: ffff88801b5890c0 R15: ffff88802418cc80
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
rcu: rcu_preempt kthread starved for 10526 jiffies! g12709 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:27848 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
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
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: 5493 Comm: syz.1.31 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:227 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x32/0x80 kernel/kcov.c:300
Code: 84 a1 8a 7e 65 8b 15 85 a1 8a 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 34 16 00 00 00 74 4e 8b 91 10 16 00 00 <83> fa 03 75 43 48 8b 91 18 16 00 00 44 8b 89 14 16 00 00 49 c1 e1
RSP: 0018:ffffc9000314f9f8 EFLAGS: 00000046
RAX: ffffffff8167fde4 RBX: 0000000000000046 RCX: ffff88805b62d940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000314fab0 R08: dffffc0000000000 R09: fffffbfff1ad32b6
R10: fffffbfff1ad32b6 R11: 1ffffffff1ad32b5 R12: 0000000000000000
R13: dffffc0000000000 R14: 1ffff92000629f40 R15: dffffc0000000000
FS: 00007f484fc9c6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002006b000 CR3: 0000000060125000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:127 [inline]
arch_irqs_disabled arch/x86/include/asm/irqflags.h:134 [inline]
seqcount_lockdep_reader_access+0x144/0x1c0 include/linux/seqlock.h:105
timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
ktime_get+0x7b/0x270 kernel/time/timekeeping.c:831
common_hrtimer_rearm+0x5d/0x110 kernel/time/posix-timers.c:303
posixtimer_rearm+0x131/0x340 kernel/time/posix-timers.c:329
dequeue_signal+0x174/0x440 kernel/signal.c:696
get_signal+0x6fe/0x12c0 kernel/signal.c:2781
arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867
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: 0033:0x7f4850a1e809
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:00007f484fc9c0e8 EFLAGS: 00000246
RAX: fffffffffffffffc RBX: 00007f4850be3fa8 RCX: 00007f4850a1e809
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4850be3fa8
RBP: 00007f4850be3fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4850be3fac
R13: 0000000000000000 R14: 00007ffc03e5e4f0 R15: 00007ffc03e5e5d8
sched: RT throttling activated