rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11487
rcu: (detected by 0, t=10502 jiffies, g=106073, q=4762 ncpus=1)
task:syz.5.1406 state:R running task stack:26032 pid:11487 tgid:11482 ppid:10136 task_flags:0x400140 flags:0x00080000
Call Trace:
sched_show_task+0x4aa/0x5f0 kernel/sched/core.c:8250
rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:292 [inline]
print_other_cpu_stall+0xfbf/0x1350 kernel/rcu/tree_stall.h:683
check_cpu_stall kernel/rcu/tree_stall.h:860 [inline]
rcu_pending kernel/rcu/tree.c:3744 [inline]
rcu_sched_clock_irq+0x9fe/0x10e0 kernel/rcu/tree.c:2749
update_process_times+0x234/0x2d0 kernel/time/timer.c:2475
tick_sched_handle kernel/time/tick-sched.c:296 [inline]
tick_nohz_handler+0x38f/0x6b0 kernel/time/tick-sched.c:317
__run_hrtimer kernel/time/hrtimer.c:2074 [inline]
__hrtimer_run_queues+0x3a0/0xaf0 kernel/time/hrtimer.c:2131
hrtimer_interrupt+0x4c2/0xa80 kernel/time/hrtimer.c:2250
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x5b/0xb0 kernel/rcu/tree.c:753
Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 1b 46 88 00 48 c7 c3 98 8e a7 93 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 75 35 8b 03 65 48 ff 0d f7 f7 fa 11 74 11 83 e0 04 c1 e8 02
RSP: 0018:ffffc90004d8f7a0 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: ffff8880b8433e98 RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff8bcc6c60 RDI: ffffffff8bcc6c20
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000004 R12: ffff888032278000
R13: dffffc0000000000 R14: ffffffff8db7b7d0 R15: dffffc0000000000
rcu_read_lock_held_common kernel/rcu/update.c:109 [inline]
rcu_read_lock_sched_held+0x15/0x70 kernel/rcu/update.c:124
task_css_set include/linux/cgroup.h:535 [inline]
task_dfl_cgroup include/linux/cgroup.h:604 [inline]
____bpf_get_current_ancestor_cgroup_id kernel/bpf/helpers.c:432 [inline]
bpf_get_current_ancestor_cgroup_id+0x108/0x3f0 kernel/bpf/helpers.c:425
bpf_prog_e5e630a6fb1d4158+0x58/0x5e
bpf_dispatcher_nop_func include/linux/bpf.h:1488 [inline]
__bpf_prog_run include/linux/filter.h:779 [inline]
bpf_prog_run include/linux/filter.h:786 [inline]
bpf_test_run+0x354/0x830 net/bpf/test_run.c:422
bpf_prog_test_run_skb+0xe35/0x2230 net/bpf/test_run.c:1225
bpf_prog_test_run+0x2cb/0x340 kernel/bpf/syscall.c:4821
__sys_bpf+0xa22/0xd90 kernel/bpf/syscall.c:6405
__do_sys_bpf kernel/bpf/syscall.c:6506 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6503 [inline]
__x64_sys_bpf+0xba/0xd0 kernel/bpf/syscall.c:6503
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3c7bb3e1d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3c79d33028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f3c7bdc6270 RCX: 00007f3c7bb3e1d9
RDX: 000000000000002d RSI: 0000200000000940 RDI: 000000000000000a
RBP: 00007f3c7bbd5888 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3c7bdc6308 R14: 00007f3c7bdc6270 R15: 00007fffe5162da8
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g106073 f0x0 RCU_GP_WAIT_FQS(5) ->state=I
rcu: Possible timer handling issue on cpu=0 timer-softirq=47836
rcu: rcu_preempt kthread starved for 10502 jiffies! g106073 f0x0 RCU_GP_WAIT_FQS(5) ->state=I ->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:I stack:27760 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x16d9/0x5700 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7376
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
kthread+0x38b/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 11487 Comm: syz.5.1406 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x5b/0xb0 kernel/rcu/tree.c:753
Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 1b 46 88 00 48 c7 c3 98 8e a7 93 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 75 35 8b 03 65 48 ff 0d f7 f7 fa 11 74 11 83 e0 04 c1 e8 02
RSP: 0018:ffffc90004d8f7a0 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: ffff8880b8433e98 RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff8bcc6c60 RDI: ffffffff8bcc6c20
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000004 R12: ffff888032278000
R13: dffffc0000000000 R14: ffffffff8db7b7d0 R15: dffffc0000000000
FS: 00007f3c79d336c0(0000) GS:ffff8881249bb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd658e75000 CR3: 0000000052794000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
rcu_read_lock_held_common kernel/rcu/update.c:109 [inline]
rcu_read_lock_sched_held+0x15/0x70 kernel/rcu/update.c:124
task_css_set include/linux/cgroup.h:535 [inline]
task_dfl_cgroup include/linux/cgroup.h:604 [inline]
____bpf_get_current_ancestor_cgroup_id kernel/bpf/helpers.c:432 [inline]
bpf_get_current_ancestor_cgroup_id+0x108/0x3f0 kernel/bpf/helpers.c:425
bpf_prog_e5e630a6fb1d4158+0x58/0x5e
bpf_dispatcher_nop_func include/linux/bpf.h:1488 [inline]
__bpf_prog_run include/linux/filter.h:779 [inline]
bpf_prog_run include/linux/filter.h:786 [inline]
bpf_test_run+0x354/0x830 net/bpf/test_run.c:422
bpf_prog_test_run_skb+0xe35/0x2230 net/bpf/test_run.c:1225
bpf_prog_test_run+0x2cb/0x340 kernel/bpf/syscall.c:4821
__sys_bpf+0xa22/0xd90 kernel/bpf/syscall.c:6405
__do_sys_bpf kernel/bpf/syscall.c:6506 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6503 [inline]
__x64_sys_bpf+0xba/0xd0 kernel/bpf/syscall.c:6503
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3c7bb3e1d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3c79d33028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f3c7bdc6270 RCX: 00007f3c7bb3e1d9
RDX: 000000000000002d RSI: 0000200000000940 RDI: 000000000000000a
RBP: 00007f3c7bbd5888 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3c7bdc6308 R14: 00007f3c7bdc6270 R15: 00007fffe5162da8