rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5169/1:b..l (detected by 0, t=10502 jiffies, g=10913, q=59) task:syz-executor.3 state:R running task stack: 0 pid: 5169 ppid: 3989 flags:0x0000000c 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 preempt_schedule_common+0x140/0x260 kernel/sched/core.c:6552 preempt_schedule+0x64/0x84 kernel/sched/core.c:6577 __local_bh_enable_ip+0x254/0x470 kernel/softirq.c:390 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline] _raw_spin_unlock_bh+0xf8/0x180 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:408 [inline] __fib6_clean_all+0x2ac/0x428 net/ipv6/ip6_fib.c:2257 fib6_clean_all+0x3c/0x50 net/ipv6/ip6_fib.c:2266 rt6_sync_down_dev net/ipv6/route.c:4912 [inline] rt6_disable_ip+0x5e8/0x6ac net/ipv6/route.c:4917 addrconf_ifdown+0x150/0x1814 net/ipv6/addrconf.c:3777 addrconf_notify+0x350/0xc58 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 __dev_notify_flags+0x2ac/0x534 dev_change_flags+0xc8/0x154 net/core/dev.c:8889 dev_ifsioc+0x140/0xfe4 net/core/dev_ioctl.c:324 dev_ioctl+0x4e0/0xd3c net/core/dev_ioctl.c:587 sock_do_ioctl+0x1dc/0x2dc net/socket.c:1154 sock_ioctl+0x4f0/0x8ac net/socket.c:1257 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __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 rcu: rcu_preempt kthread starved for 10489 jiffies! g10913 f0x0 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 preempt_schedule_common+0x140/0x260 kernel/sched/core.c:6552 preempt_schedule+0x64/0x84 kernel/sched/core.c:6577 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] _raw_spin_unlock_irqrestore+0x114/0x158 kernel/locking/spinlock.c:194 debug_object_free+0x2ac/0x454 lib/debugobjects.c:850 destroy_timer_on_stack kernel/time/timer.c:759 [inline] schedule_timeout+0x1f0/0x344 kernel/time/timer.c:1918 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-executor.0 state:R running task stack: 0 pid: 5165 ppid: 3982 flags:0x00000001 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:580 arch_local_irq_restore arch/arm64/include/asm/irqflags.h:122 [inline] lock_release+0x504/0xa1c kernel/locking/lockdep.c:5646 __might_fault+0xf4/0x128 mm/memory.c:5328 setup_sigframe arch/arm64/kernel/signal.c:627 [inline] setup_rt_frame arch/arm64/kernel/signal.c:789 [inline] handle_signal arch/arm64/kernel/signal.c:830 [inline] do_signal arch/arm64/kernel/signal.c:905 [inline] do_notify_resume+0xf18/0x32b8 arch/arm64/kernel/signal.c:943 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 107s! Showing busy workqueues and worker pools: workqueue events: flags=0x0 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=5/256 refcnt=6 pending: psi_avgs_work, psi_avgs_work, nsim_dev_trap_report_work, nsim_dev_trap_report_work, nsim_dev_trap_report_work pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=13/256 refcnt=14 in-flight: 4026:switchdev_deferred_process_work pending: kfree_rcu_monitor, psi_avgs_work, psi_avgs_work, vmstat_shepherd, nsim_dev_trap_report_work, nsim_dev_trap_report_work, psi_avgs_work, linkwatch_event, psi_avgs_work, ovs_dp_masks_rebalance, ovs_dp_masks_rebalance, rht_deferred_worker workqueue events_long: flags=0x0 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=5/256 refcnt=6 pending: defense_work_handler, defense_work_handler, defense_work_handler, defense_work_handler, defense_work_handler pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: defense_work_handler workqueue events_unbound: flags=0x2 pwq 4: cpus=0-1 flags=0x5 nice=0 active=3/512 refcnt=5 in-flight: 9:fsnotify_connector_destroy_workfn, 580:fsnotify_mark_destroy_workfn pending: flush_memcg_stats_dwork workqueue events_power_efficient: flags=0x82 pwq 4: cpus=0-1 flags=0x5 nice=0 active=5/256 refcnt=7 pending: fb_flashcursor, wg_ratelimiter_gc_entries, nf_flow_offload_work_gc, gc_worker, check_lifetime workqueue rcu_gp: flags=0x8 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: process_srcu workqueue mm_percpu_wq: flags=0x8 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: vmstat_update pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: vmstat_update workqueue writeback: flags=0x4a pwq 4: cpus=0-1 flags=0x5 nice=0 active=4/256 refcnt=6 pending: wb_workfn, wb_workfn, wb_update_bandwidth_workfn, wb_workfn workqueue kblockd: flags=0x18 pwq 1: cpus=0 node=0 flags=0x0 nice=-20 active=4/256 refcnt=5 pending: blk_mq_timeout_work, blk_mq_timeout_work, blk_mq_timeout_work, blk_mq_timeout_work workqueue dm_bufio_cache: flags=0x8 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: work_fn workqueue mld: flags=0x40008 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/1 refcnt=2 pending: mld_ifc_work workqueue krxrpcd: flags=0x0 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/1 refcnt=2 pending: rxrpc_peer_keepalive_worker workqueue bat_events: flags=0xe000a pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=38 in-flight: 148:batadv_nc_worker inactive: batadv_mcast_mla_update, batadv_mcast_mla_update, batadv_mcast_mla_update, batadv_mcast_mla_update, batadv_mcast_mla_update, batadv_nc_worker, batadv_nc_worker, batadv_nc_worker, batadv_nc_worker, batadv_purge_orig, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_purge_orig, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_iv_send_outstanding_bat_ogm_packet, batadv_purge_orig, batadv_purge_orig, batadv_tt_purge, batadv_tt_purge, batadv_tt_purge, batadv_bla_periodic_work , batadv_dat_purge, batadv_bla_periodic_work, batadv_dat_purge, batadv_tt_purge workqueue hci0: flags=0xa0012 pwq 5: cpus=0-1 flags=0x4 nice=-20 active=1/1 refcnt=3 pending: hci_conn_timeout workqueue hci2: flags=0xa0012 pwq 5: cpus=0-1 flags=0x4 nice=-20 active=1/1 refcnt=3 pending: hci_conn_timeout workqueue hci3: flags=0xa0012 pwq 5: cpus=0-1 flags=0x4 nice=-20 active=1/1 refcnt=3 pending: hci_conn_timeout workqueue hci4: flags=0xa0012 pwq 5: cpus=0-1 flags=0x4 nice=-20 active=1/1 refcnt=3 pending: hci_conn_timeout workqueue wg-kex-wg0: flags=0x6 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/256 refcnt=3 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg0: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg1: flags=0x6 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/256 refcnt=3 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg1: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-crypt-wg2: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg0: flags=0x6 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/256 refcnt=3 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg0: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg1: flags=0x6 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/256 refcnt=3 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg1: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-crypt-wg2: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg0: flags=0x6 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/256 refcnt=3 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg0: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg0: flags=0x6 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/256 refcnt=3 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg0: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg1: flags=0x6 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/256 refcnt=3 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg1: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg1: flags=0x6 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/256 refcnt=3 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg1: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-crypt-wg2: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-crypt-wg2: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg0: flags=0x6 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/256 refcnt=3 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg0: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg1: flags=0x6 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/256 refcnt=3 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg1: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-crypt-wg2: flags=0x28 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/256 refcnt=2 pending: wg_packet_encrypt_worker workqueue phy3: flags=0xa0002 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=3 pending: ieee80211_iface_work workqueue phy4: flags=0xa0002 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=3 pending: ieee80211_iface_work workqueue phy5: flags=0xa0002 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=3 pending: ieee80211_iface_work workqueue phy6: flags=0xa0002 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=4 in-flight: 284:ieee80211_iface_work inactive: ieee80211_iface_work workqueue phy7: flags=0xa0002 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=4 in-flight: 136:ieee80211_iface_work inactive: ieee80211_iface_work workqueue phy8: flags=0xa0002 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=4 in-flight: 621:ieee80211_iface_work inactive: ieee80211_iface_work workqueue phy9: flags=0xa0002 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=3 pending: ieee80211_iface_work workqueue phy10: flags=0xa0002 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=3 pending: ieee80211_iface_work workqueue phy11: flags=0xa0002 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=3 pending: ieee80211_iface_work workqueue phy12: flags=0xa0002 pwq 4: cpus=0-1 flags=0x5 nice=0 active=1/1 refcnt=3 pending: ieee80211_iface_work pool 0: cpus=0 node=0 flags=0x0 nice=0 hung=108s workers=11 idle: 4159 4158 7 5114 1524 4023 4160 4021 4163 13 pool 4: cpus=0-1 flags=0x5 nice=0 hung=107s workers=7 manager: 364