rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6202/1:b..l P3559/1:b..l
(detected by 1, t=10502 jiffies, g=19713, q=61)
task:udevd state:R running task stack:23280 pid: 3559 ppid: 1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 kernel/sched/core.c:6395
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571
preempt_schedule+0xbc/0xd0 kernel/sched/core.c:6596
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
_raw_spin_unlock_irqrestore+0x10d/0x120 kernel/locking/spinlock.c:194
spin_unlock_irqrestore include/linux/spinlock.h:419 [inline]
__wake_up_common_lock kernel/sched/wait.c:140 [inline]
__wake_up_sync_key+0x128/0x190 kernel/sched/wait.c:205
sock_def_readable+0x136/0x250 net/core/sock.c:3101
__netlink_sendskb net/netlink/af_netlink.c:1264 [inline]
netlink_sendskb+0x97/0x130 net/netlink/af_netlink.c:1270
netlink_sendmsg+0x8ba/0xbe0 net/netlink/af_netlink.c:1923
sock_sendmsg_nosec net/socket.c:706 [inline]
__sock_sendmsg net/socket.c:718 [inline]
____sys_sendmsg+0x5be/0x8f0 net/socket.c:2446
___sys_sendmsg+0x236/0x2e0 net/socket.c:2500
__sys_sendmsg net/socket.c:2529 [inline]
__do_sys_sendmsg net/socket.c:2538 [inline]
__se_sys_sendmsg+0x1b7/0x2a0 net/socket.c:2536
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f03cb627407
RSP: 002b:00007ffff6b8be90 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f03cb539880 RCX: 00007f03cb627407
RDX: 0000000000000000 RSI: 00007ffff6b8bef0 RDI: 0000000000000004
RBP: 000055c6ed242850 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000b3
R13: 000055c6ed2389e0 R14: 0000000000000000 R15: 0000000000000000
task:syz.0.576 state:R running task stack:26608 pid: 6202 ppid: 4187 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 kernel/sched/core.c:6395
preempt_schedule_irq+0xbb/0x160 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:trace_lock_release include/trace/events/lock.h:58 [inline]
RIP: 0010:lock_release+0xae/0x8a0 kernel/locking/lockdep.c:5634
Code: 83 fb 08 0f 83 4e 05 00 00 89 d8 c1 e8 06 48 8d 3c c5 e8 ea 8a 8d be 08 00 00 00 e8 6c b9 60 00 89 d8 48 0f a3 05 9a 91 2d 0c <73> 0d e8 2b 44 07 00 84 c0 0f 84 53 05 00 00 48 c7 c0 84 1e 8b 8d
RSP: 0018:ffffc9000329f820 EFLAGS: 00000257
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff815d5944
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d8aeae8
RBP: ffffc9000329f940 R08: ffffffff8d8aeaef R09: 1ffffffff1b15d5d
R10: dffffc0000000000 R11: fffffbfff1b15d5e R12: 1ffff92000653f10
R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000
rcu_read_unlock include/linux/rcupdate.h:773 [inline]
percpu_ref_tryget_many include/linux/percpu-refcount.h:250 [inline]
percpu_ref_tryget+0xcf/0x150 include/linux/percpu-refcount.h:266
obj_cgroup_tryget include/linux/memcontrol.h:800 [inline]
get_obj_cgroup_from_current mm/memcontrol.c:2930 [inline]
__memcg_kmem_charge_page+0x230/0x380 mm/memcontrol.c:3056
memcg_kmem_charge_page include/linux/memcontrol.h:1696 [inline]
memcg_charge_kernel_stack kernel/fork.c:418 [inline]
dup_task_struct+0x391/0xb70 kernel/fork.c:904
copy_process+0x61f/0x3ec0 kernel/fork.c:2122
kernel_clone+0x23f/0x990 kernel/fork.c:2681
__do_sys_clone3 kernel/fork.c:2956 [inline]
__se_sys_clone3+0x312/0x3d0 kernel/fork.c:2940
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f06cd943c49
RSP: 002b:00007ffec28c0128 EFLAGS: 00000202 ORIG_RAX: 00000000000001b3
RAX: ffffffffffffffda RBX: 00007f06cd8ff1e0 RCX: 00007f06cd943c49
RDX: 00007f06cd8ff1e0 RSI: 0000000000000058 RDI: 00007ffec28c0180
RBP: 00007f06cb7366c0 R08: 00007f06cb7366c0 R09: 00007ffec28c0267
R10: 0000000000000008 R11: 0000000000000202 R12: ffffffffffffffe8
R13: 0000000000000004 R14: 00007ffec28c0180 R15: 00007ffec28c0268
rcu: rcu_preempt kthread starved for 9896 jiffies! g19713 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27088 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11c3/0x4350 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
rcu_gp_fqs_loop+0x2be/0x11f0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x9a/0x370 kernel/rcu/tree.c:2145
kthread+0x42e/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 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 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+0x1110/0x1270 kernel/rcu/tree_stall.h:592
check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
rcu_pending kernel/rcu/tree.c:3936 [inline]
rcu_sched_clock_irq+0x845/0x1120 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:2021
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:1685 [inline]
__hrtimer_run_queues+0x4b0/0xb60 kernel/time/hrtimer.c:1749
hrtimer_interrupt+0x397/0x8b0 kernel/time/hrtimer.c:1811
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:default_idle+0xb/0x10 arch/x86/kernel/process.c:730
Code: b7 48 89 df e8 56 a7 f5 f7 eb ad e8 3f ac f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d 57 64 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:ffffc90000d67d48 EFLAGS: 000002c2
RAX: 60938e64f05b8e00 RBX: ffff88813fe68000 RCX: 60938e64f05b8e00
RDX: 0000000000000001 RSI: ffffffff8a2b2be0 RDI: ffffffff8a7a2a40
RBP: ffffc90000d67e80 R08: ffff8880b913b30b R09: 1ffff11017227661
R10: dffffc0000000000 R11: ffffed1017227662 R12: 1ffff920001acfb4
R13: dffffc0000000000 R14: 1ffff11027fcd000 R15: 0000000000000000
default_idle_call+0x81/0xc0 kernel/sched/idle.c:112
cpuidle_idle_call kernel/sched/idle.c:202 [inline]
do_idle+0x251/0x650 kernel/sched/idle.c:326
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:424
start_secondary+0x32f/0x430 arch/x86/kernel/smpboot.c:281
secondary_startup_64_no_verify+0xb1/0xbb