rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4303/1:b..l P3547/1:b..l
(detected by 0, t=10502 jiffies, g=11017, q=322)
task:udevd state:R running task stack:24248 pid: 3547 ppid: 1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
irqentry_exit+0x53/0x80 kernel/entry/common.c:432
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:debug_lockdep_rcu_enabled+0x28/0x30 kernel/rcu/update.c:280
Code: cc cc 31 c0 83 3d fb 71 cb 03 00 74 1d 83 3d 82 a4 cb 03 00 74 14 65 48 8b 0d e4 3a c3 75 31 c0 83 b9 ec 0a 00 00 00 0f 94 c0 00 00 cc cc 00 00 cc 41 56 53 89 fb e8 d6 0d 00 00 41 89 c6 83
RSP: 0018:ffffc9000e017570 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 000000000000000c RCX: ffff88807c568000
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: ffffffff8af9e940
RBP: 00000000000e44f3 R08: dffffc0000000000 R09: fffffbfff2131819
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc9000e017bd0
R13: ffff8881471438f8 R14: ffffc90000734798 R15: dffffc0000000000
rcu_read_lock include/linux/rcupdate.h:740 [inline]
__d_lookup+0x80/0x730 fs/dcache.c:2428
lookup_fast+0xdc/0x7b0 fs/namei.c:1621
walk_component+0x115/0x610 fs/namei.c:1972
link_path_walk+0x642/0xd90 fs/namei.c:-1
path_openat+0x249/0x2f20 fs/namei.c:3738
do_filp_open+0x21c/0x460 fs/namei.c:3769
do_sys_openat2+0x13b/0x4f0 fs/open.c:1253
do_sys_open fs/open.c:1269 [inline]
__do_sys_openat fs/open.c:1285 [inline]
__se_sys_openat fs/open.c:1280 [inline]
__x64_sys_openat+0x243/0x290 fs/open.c:1280
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0x80 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5afbecf9a4
RSP: 002b:00007ffd489bc490 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007f5afbecf9a4
RDX: 0000000000080000 RSI: 00007ffd489bc5c8 RDI: 00000000ffffff9c
RBP: 00007ffd489bc5c8 R08: 0000000000000008 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000
R13: 0000558896bd6b42 R14: 0000000000000001 R15: 0000000000000000
task:kworker/u4:11 state:R running task stack:25464 pid: 4303 ppid: 2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
irqentry_exit+0x53/0x80 kernel/entry/common.c:432
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 1c 9b 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0000:ffffc900032efa80 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff9200065df5c RCX: 1ffff9200065defc
RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: ffffffff8af9e940
RBP: ffffc900032efbd8 R08: dffffc0000000000 R09: fffffbfff2131819
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200065df58
R13: dffffc0000000000 R14: ffffc900032efae0 R15: 0000000000000246
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+0xc1/0x5b0 net/batman-adv/network-coding.c:723
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: rcu_preempt kthread starved for 10341 jiffies! g11017 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:26712 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
kthread+0x3f6/0x4f0 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: 0 Comm: swapper/0 Not tainted 5.15.180-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
print_other_cpu_stall+0x137a/0x14d0 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+0xa38/0x1150 kernel/rcu/tree.c:2619
update_process_times+0x196/0x200 kernel/time/timer.c:1818
tick_sched_handle kernel/time/tick-sched.c:254 [inline]
tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
__run_hrtimer kernel/time/hrtimer.c:1690 [inline]
__hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1754
hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1816
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x13b/0x4b0 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:default_idle+0xb/0x10 arch/x86/kernel/process.c:723
Code: 07 80 c1 03 38 c1 7c b5 4c 89 e7 e8 af 84 81 f7 eb ab e8 88 80 f6 ff 00 00 cc cc 00 00 cc cc 66 90 0f 00 2d 07 1b 5d 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffffff8c807da8 EFLAGS: 000002c2
RAX: 8dfc72e85a27d100 RBX: ffffffff8c8bd680 RCX: 000000000002c4f4
RDX: 0000000000000001 RSI: ffffffff8aab18e0 RDI: ffffffff8af9e940
RBP: ffffffff8c807ef8 R08: dffffc0000000000 R09: ffffed10171c765a
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff1900fce
R13: 1ffffffff1917ad0 R14: 0000000000000000 R15: dffffc0000000000
default_idle_call+0x81/0xc0 kernel/sched/idle.c:112
cpuidle_idle_call kernel/sched/idle.c:194 [inline]
do_idle+0x271/0x670 kernel/sched/idle.c:306
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
start_kernel+0x48c/0x540 init/main.c:1140
secondary_startup_64_no_verify+0xb1/0xbb