rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P136/1:b..l (detected by 1, t=10502 jiffies, g=11629, q=3246) task:kworker/u4:1 state:R running task stack: 0 pid: 136 ppid: 2 flags:0x00000008 Workqueue: writeback wb_workfn (flush-259:0) Call trace: __switch_to+0x2f4/0x558 arch/arm64/kernel/process.c:521 context_switch kernel/sched/core.c:5030 [inline] __schedule+0xe00/0x1c0c kernel/sched/core.c:6376 preempt_schedule_irq+0x90/0x214 kernel/sched/core.c:6780 arm64_preempt_schedule_irq+0x14c/0x21c 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 arch_local_irq_restore arch/arm64/include/asm/irqflags.h:122 [inline] mod_lruvec_page_state include/linux/vmstat.h:497 [inline] dec_lruvec_page_state include/linux/vmstat.h:555 [inline] clear_page_dirty_for_io+0x548/0x864 mm/page-writeback.c:2761 mpage_submit_page fs/ext4/inode.c:2093 [inline] mpage_process_page_bufs+0x618/0x8c4 fs/ext4/inode.c:2227 mpage_prepare_extent_to_map+0x9a0/0xda4 fs/ext4/inode.c:2655 ext4_writepages+0x7b0/0x2c14 fs/ext4/inode.c:2783 do_writepages+0x36c/0x578 mm/page-writeback.c:2386 __writeback_single_inode+0x148/0x11f0 fs/fs-writeback.c:1647 writeback_sb_inodes+0x7fc/0x1378 fs/fs-writeback.c:1930 __writeback_inodes_wb+0x110/0x394 fs/fs-writeback.c:2001 wb_writeback+0x3ec/0xe44 fs/fs-writeback.c:2106 wb_check_old_data_flush fs/fs-writeback.c:2206 [inline] wb_do_writeback fs/fs-writeback.c:2259 [inline] wb_workfn+0xa18/0xdd8 fs/fs-writeback.c:2288 process_one_work+0x79c/0x1140 kernel/workqueue.c:2310 worker_thread+0x8f4/0x101c kernel/workqueue.c:2457 kthread+0x374/0x454 kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:855 rcu: rcu_preempt kthread timer wakeup didn't happen for 1233 jiffies! g11629 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=6308 rcu: rcu_preempt kthread starved for 1234 jiffies! g11629 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack: 0 pid: 15 ppid: 2 flags:0x00000008 Call trace: __switch_to+0x2f4/0x558 arch/arm64/kernel/process.c:521 context_switch kernel/sched/core.c:5030 [inline] __schedule+0xe00/0x1c0c kernel/sched/core.c:6376 schedule+0x11c/0x1c8 kernel/sched/core.c:6459 schedule_timeout+0x180/0x2c8 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x25c/0x11f0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xc4/0x2a8 kernel/rcu/tree.c:2145 kthread+0x374/0x454 kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:855 rcu: Stack dump where RCU GP kthread last ran: Task dump for CPU 1: task:kworker/1:1 state:R running task stack: 0 pid: 25 ppid: 2 flags:0x0000000a Workqueue: wg-crypt-wg1 wg_packet_tx_worker Call trace: dump_backtrace+0x0/0x43c arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 sched_show_task+0x3c8/0x4b4 kernel/sched/core.c:8640 dump_cpu_task+0x84/0xa8 kernel/sched/core.c:10927 rcu_check_gp_kthread_starvation+0x1e8/0x274 kernel/rcu/tree_stall.h:488 print_other_cpu_stall+0x1a24/0x1c10 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+0x1558/0x1810 kernel/rcu/tree.c:2619 update_process_times+0x1c4/0x260 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x30c/0x4bc kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1690 [inline] __hrtimer_run_queues+0x3fc/0xb6c kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x2bc/0xb5c kernel/time/hrtimer.c:1816 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/0x76c kernel/irq/chip.c:930 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq_desc kernel/irq/irqdesc.c:652 [inline] handle_domain_irq+0x144/0x1fc kernel/irq/irqdesc.c:707 gic_handle_irq+0x78/0x1c8 drivers/irqchip/irq-gic-v3.c:765 call_on_irq_stack+0x24/0x30 arch/arm64/kernel/entry.S:855 do_interrupt_handler+0x6c/0x88 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 __cmpwait_case_32 arch/arm64/include/asm/cmpxchg.h:252 [inline] __cmpwait arch/arm64/include/asm/cmpxchg.h:278 [inline] queued_spin_lock_slowpath+0x13c/0x798 kernel/locking/qspinlock.c:382 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x2ec/0x2f0 kernel/locking/spinlock_debug.c:115 __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_lock+0xb8/0x10c kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:363 [inline] __dev_xmit_skb net/core/dev.c:3911 [inline] __dev_queue_xmit+0x840/0x2800 net/core/dev.c:4253 dev_queue_xmit+0x24/0x34 net/core/dev.c:4321 neigh_hh_output include/net/neighbour.h:493 [inline] neigh_output include/net/neighbour.h:507 [inline] ip6_finish_output2+0x129c/0x1a14 net/ipv6/ip6_output.c:130 __ip6_finish_output net/ipv6/ip6_output.c:201 [inline] ip6_finish_output+0x570/0x6dc net/ipv6/ip6_output.c:211 NF_HOOK_COND include/linux/netfilter.h:291 [inline] ip6_output+0x274/0x500 net/ipv6/ip6_output.c:234 dst_output include/net/dst.h:452 [inline] ip6_local_out+0x120/0x15c net/ipv6/output_core.c:161 ip6tunnel_xmit include/net/ip6_tunnel.h:160 [inline] udp_tunnel6_xmit_skb+0x40c/0x8e8 net/ipv6/ip6_udp_tunnel.c:109 send6+0x4e4/0x770 drivers/net/wireguard/socket.c:152 wg_socket_send_skb_to_peer+0xf8/0x1a4 drivers/net/wireguard/socket.c:178 wg_packet_create_data_done drivers/net/wireguard/send.c:251 [inline] wg_packet_tx_worker+0x19c/0x6c4 drivers/net/wireguard/send.c:276 process_one_work+0x79c/0x1140 kernel/workqueue.c:2310 worker_thread+0x8f4/0x101c kernel/workqueue.c:2457 kthread+0x374/0x454 kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:855