rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11984 rcu: (detected by 0, t=10502 jiffies, g=68657, q=1378 ncpus=2) task:syz.3.1076 state:R running task stack:23776 pid:11984 tgid:11980 ppid:11648 flags:0x00004002 Call Trace: sched_show_task+0x506/0x6d0 kernel/sched/core.c:7432 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:263 [inline] print_other_cpu_stall+0x11fe/0x15b0 kernel/rcu/tree_stall.h:642 check_cpu_stall kernel/rcu/tree_stall.h:808 [inline] rcu_pending kernel/rcu/tree.c:4343 [inline] rcu_sched_clock_irq+0xa2c/0x10d0 kernel/rcu/tree.c:2670 update_process_times+0x1ce/0x230 kernel/time/timer.c:2519 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x37c/0x500 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x551/0xd50 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1043 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:unwind_next_frame+0x476/0x22d0 arch/x86/kernel/unwind_orc.c:512 Code: fc ff df 42 0f b6 04 20 84 c0 0f 85 64 17 00 00 c6 03 01 48 c7 c2 a0 49 e8 8b 48 8b 6c 24 50 4c 8d 7a 04 48 8d 5a 05 4c 89 f8 <48> c1 e8 03 48 89 44 24 70 42 0f b6 04 20 84 c0 48 89 54 24 10 0f RSP: 0018:ffffc900000073b0 EFLAGS: 00000202 RAX: ffffffff907fd57e RBX: ffffffff907fd57f RCX: ffffffff900af39c RDX: ffffffff907fd57a RSI: ffffffff907fd57a RDI: 0000000000000001 RBP: ffffc90000007530 R08: 0000000000000001 R09: 0000000000000000 R10: ffffc900000074e0 R11: fffff52000000ea8 R12: dffffc0000000000 R13: ffffc900000074e0 R14: ffffffff907fd57f R15: ffffffff907fd57e __unwind_start+0x59a/0x740 arch/x86/kernel/unwind_orc.c:760 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe5/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2250 [inline] slab_free mm/slub.c:4474 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4549 llc_rcv+0x6f1/0xc10 __netif_receive_skb_one_core net/core/dev.c:5662 [inline] __netif_receive_skb+0x2e0/0x650 net/core/dev.c:5775 process_backlog+0x662/0x15b0 net/core/dev.c:6107 __napi_poll+0xcb/0x490 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6962 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 local_bh_enable include/linux/bottom_half.h:33 [inline] bpf_test_run+0x56b/0xa90 net/bpf/test_run.c:436 bpf_prog_test_run_skb+0xc97/0x1820 net/bpf/test_run.c:1094 bpf_prog_test_run+0x334/0x3b0 kernel/bpf/syscall.c:4313 __sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5728 __do_sys_bpf kernel/bpf/syscall.c:5817 [inline] __se_sys_bpf kernel/bpf/syscall.c:5815 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5815 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb25037def9 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:00007fb2511f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fb250535f80 RCX: 00007fb25037def9 RDX: 0000000000000050 RSI: 0000000020000080 RDI: 000000000000000a RBP: 00007fb2503f0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb250535f80 R15: 00007ffeb1bf44e8 rcu: rcu_preempt kthread starved for 10520 jiffies! g68657 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:24912 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111