rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4361/1:b..l
(detected by 0, t=10502 jiffies, g=20037, q=35)
task:kworker/u4:14 state:R running task stack:20896 pid: 4361 ppid: 2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6780
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:ffffc900032efaa0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 8416d1ba9a6b5d00
RDX: 0000000000000000 RSI: ffffffff8a0b2260 RDI: ffffffff8a59a2c0
RBP: ffffc900032efbc0 R08: dffffc0000000000 R09: fffffbfff1ff3219
R10: fffffbfff1ff3219 R11: 1ffffffff1ff3218 R12: ffffffff8c11bea0
R13: 1ffff9200065df60 R14: 0000000000000246 R15: dffffc0000000000
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
rcu_read_lock include/linux/rcupdate.h:739 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
batadv_nc_worker+0xc9/0x5c0 net/batman-adv/network-coding.c:723
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 10528 jiffies! g20037 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:28128 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
schedule+0x11b/0x1e0 kernel/sched/core.c:6459
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:
NMI backtrace for cpu 0
CPU: 0 PID: 6724 Comm: syz.4.688 Not tainted 5.15.183-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592
check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
rcu_pending kernel/rcu/tree.c:3932 [inline]
rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:1818
tick_sched_handle kernel/time/tick-sched.c:254 [inline]
tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
__run_hrtimer kernel/time/hrtimer.c:1690 [inline]
__hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_is_held_type+0x9/0x190 kernel/locking/lockdep.c:5651
Code: 60 0e 0b 8a 48 c7 c6 a0 0e 0b 8a e8 11 39 f5 ff 0f 0b eb bf e8 98 fd ff ff 0f 1f 84 00 00 00 00 00 55 41 57 41 56 41 55 41 54 <53> 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 bd ff ff
RSP: 0018:ffffc9000320faf0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 1ffff92000641f6c RCX: ffff888026b30000
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8c11bf00
RBP: ffffc9000320fc30 R08: 0000000000000000 R09: fffff52000641fc6
R10: fffff52000641fc6 R11: 1ffff92000641fc0 R12: dffffc0000000000
R13: 1ffff92000641fff R14: ffffffff8b9c9788 R15: 0000000000000000
lock_is_held include/linux/lockdep.h:287 [inline]
___might_sleep+0xa3/0x600 kernel/sched/core.c:9605
__might_fault+0x6b/0x110 mm/memory.c:5354
__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+0xb1/0x140 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: 0033:0x7f97a56f2830
Code: 10 83 e0 01 83 e2 01 88 15 c2 5e e9 00 88 05 bf 5e e9 00 c3 50 48 8d 35 89 12 1c 00 48 8d 3d 8f 12 1c 00 31 c0 e8 30 f7 ff ff <53> 89 fb 48 83 ec 10 64 8b 04 25 94 ff ff ff 85 c0 74 2a 89 fe 31
RSP: 002b:00007fff62828af8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f97a5a592d8 RCX: 00007f97a57e8f57
RDX: 00007fff62828b00 RSI: 00007fff62828c30 RDI: 0000000000000007
RBP: 0000000000000003 R08: 00007f97a5a58fa0 R09: 00007fff62828f57
R10: 0000000000000008 R11: 0000000000000246 R12: 00007f97a5a5924c
R13: 00007f97a5a59240 R14: 000000000000018d R15: 0000000000000003