rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5096/1:b..l P61/2:b..l P29/1:b..l rcu: (detected by 0, t=10502 jiffies, g=8261, q=598 ncpus=2) task:kworker/u8:2 state:R running task stack:24656 pid:29 tgid:29 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5722 Code: c1 05 da ac 96 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc90000a57a70 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff9200014af50 RCX: 000000002e9e48ae RDX: 0000000000000001 RSI: ffffffff8b2cb200 RDI: ffffffff8b9039c0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff284d858 R10: ffffffff9426c2c7 R11: 0000000000000003 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8dbb1620 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:754 [inline] batadv_iv_ogm_schedule_buff+0x5ac/0x1500 net/batman-adv/bat_iv_ogm.c:825 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:868 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:861 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x31e/0x8d0 net/batman-adv/bat_iv_ogm.c:1712 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3248 process_scheduled_works kernel/workqueue.c:3329 [inline] worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 task:kworker/u8:4 state:R running task stack:22944 pid:61 tgid:61 ppid:2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6924 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0x107/0x120 kernel/softirq.c:389 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:851 [inline] __dev_queue_xmit+0x872/0x4130 net/core/dev.c:4420 dev_queue_xmit include/linux/netdevice.h:3095 [inline] neigh_hh_output include/net/neighbour.h:526 [inline] neigh_output include/net/neighbour.h:540 [inline] ip6_finish_output2+0x1100/0x18b0 net/ipv6/ip6_output.c:137 __ip6_finish_output net/ipv6/ip6_output.c:211 [inline] ip6_finish_output+0x3f9/0x1300 net/ipv6/ip6_output.c:222 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip6_output+0x1f8/0x540 net/ipv6/ip6_output.c:243 dst_output include/net/dst.h:450 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] mld_sendpack+0x9ee/0x11d0 net/ipv6/mcast.c:1818 mld_send_initial_cr.part.0+0x1a1/0x260 net/ipv6/mcast.c:2236 mld_send_initial_cr include/linux/refcount.h:192 [inline] ipv6_mc_dad_complete+0x22c/0x2b0 net/ipv6/mcast.c:2244 addrconf_dad_completed+0xd42/0x1060 net/ipv6/addrconf.c:4339 addrconf_dad_work+0x807/0x1500 net/ipv6/addrconf.c:4267 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3248 process_scheduled_works kernel/workqueue.c:3329 [inline] worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 task:syz-executor state:R running task stack:23328 pid:5096 tgid:5096 ppid:5078 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5722 Code: c1 05 da ac 96 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc9000324fb68 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000649f6f RCX: 0000000067ce10c4 RDX: 0000000000000001 RSI: ffffffff8b2cb200 RDI: ffffffff8b9039c0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff284d858 R10: ffffffff9426c2c7 R11: 0000000000000003 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8dbb1620 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] percpu_ref_get_many include/linux/percpu-refcount.h:202 [inline] percpu_ref_get include/linux/percpu-refcount.h:222 [inline] css_get include/linux/cgroup_refcnt.h:11 [inline] css_get include/linux/cgroup_refcnt.h:8 [inline] cgroup_get include/linux/cgroup.h:351 [inline] cgroup_get_live+0xa2/0x2a0 kernel/cgroup/cgroup.c:600 init_and_link_css+0x71/0x860 kernel/cgroup/cgroup.c:5467 css_create kernel/cgroup/cgroup.c:5555 [inline] cgroup_apply_control_enable+0x4fe/0xc80 kernel/cgroup/cgroup.c:3217 cgroup_mkdir+0x39b/0x1120 kernel/cgroup/cgroup.c:5763 kernfs_iop_mkdir+0x14a/0x1d0 fs/kernfs/dir.c:1246 vfs_mkdir+0x57d/0x860 fs/namei.c:4137 do_mkdirat+0x301/0x3a0 fs/namei.c:4160 __do_sys_mkdirat fs/namei.c:4175 [inline] __se_sys_mkdirat fs/namei.c:4173 [inline] __x64_sys_mkdirat+0x114/0x170 fs/namei.c:4173 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2edb774517 RSP: 002b:00007ffc0ad228f8 EFLAGS: 00000202 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f2edb7e3977 RCX: 00007f2edb774517 RDX: 00000000000001ff RSI: 00007ffc0ad22980 RDI: 00000000ffffff9c RBP: 0000000000000001 R08: 0000000000000013 R09: 00007ffc0ad22647 R10: 0000000000000000 R11: 0000000000000202 R12: 00007f2edb7e49e6 R13: 0000000000000003 R14: 00007ffc0ad22980 R15: 00007ffc0ad229c0 rcu: rcu_preempt kthread starved for 10588 jiffies! g8261 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:27680 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2000 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2202 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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:86 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111