rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 0, t=10502 jiffies, g=3989, q=1) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294984989-4294974487), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g3989 f0x2 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: 0 pid: 15 ppid: 2 flags:0x00000008 Call trace: __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518 context_switch kernel/sched/core.c:5030 [inline] __schedule+0xf10/0x1e48 kernel/sched/core.c:6376 schedule+0x11c/0x1c8 kernel/sched/core.c:6459 schedule_timeout+0x1d8/0x344 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x26c/0x13d4 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xc4/0x2c4 kernel/rcu/tree.c:2145 kthread+0x37c/0x45c kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 rcu: Stack dump where RCU GP kthread last ran: Task dump for CPU 0: task:syz-executor104 state:R running task stack: 0 pid: 4015 ppid: 4000 flags:0x00000006 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 sched_show_task+0x43c/0x574 kernel/sched/core.c:8640 dump_cpu_task+0x84/0xa8 kernel/sched/core.c:10914 rcu_check_gp_kthread_starvation+0x1f0/0x254 kernel/rcu/tree_stall.h:488 print_other_cpu_stall+0x202c/0x2290 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+0x1894/0x1b8c kernel/rcu/tree.c:2619 update_process_times+0x1d4/0x270 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x340/0x4f8 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1686 [inline] __hrtimer_run_queues+0x458/0xca4 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x2c0/0xb64 kernel/time/hrtimer.c:1812 timer_handler drivers/clocksource/arm_arch_timer.c:659 [inline] arch_timer_handler_virt+0x74/0x88 drivers/clocksource/arm_arch_timer.c:670 handle_percpu_devid_irq+0x29c/0x7fc kernel/irq/chip.c:933 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq_desc kernel/irq/irqdesc.c:651 [inline] handle_domain_irq+0xec/0x178 kernel/irq/irqdesc.c:706 gic_handle_irq+0x78/0x1c8 drivers/irqchip/irq-gic-v3.c:758 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:899 do_interrupt_handler+0x74/0x94 arch/arm64/kernel/entry-common.c:267 el1_interrupt+0x30/0x58 arch/arm64/kernel/entry-common.c:454 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:470 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:522 arch_local_irq_enable arch/arm64/include/asm/irqflags.h:35 [inline] raw_spin_rq_unlock_irq kernel/sched/sched.h:1338 [inline] finish_lock_switch+0xc4/0x1e8 kernel/sched/core.c:4784 finish_task_switch+0x120/0x6b4 kernel/sched/core.c:4902 context_switch kernel/sched/core.c:5033 [inline] __schedule+0xf14/0x1e48 kernel/sched/core.c:6376 preempt_schedule_irq+0x90/0x274 kernel/sched/core.c:6780 arm64_preempt_schedule_irq+0x174/0x2c4 arch/arm64/kernel/entry-common.c:260 el1_interrupt+0x40/0x58 arch/arm64/kernel/entry-common.c:463 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:470 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:522 __wake_up_sync_key+0x34/0x1ac kernel/sched/wait.c:201 __unix_dgram_recvmsg+0x4c4/0xe64 net/unix/af_unix.c:2341 unix_dgram_recvmsg+0xd4/0xec net/unix/af_unix.c:2412 ____sys_recvmsg+0x234/0x720 ___sys_recvmsg+0x240/0x2cc net/socket.c:2692 do_recvmmsg+0x310/0x9a4 net/socket.c:2786 __sys_recvmmsg net/socket.c:2865 [inline] __do_sys_recvmmsg net/socket.c:2888 [inline] __se_sys_recvmmsg net/socket.c:2881 [inline] __arm64_sys_recvmmsg+0x180/0x23c net/socket.c:2881 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584