rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=63e/1/0x4000000000000000 softirq=44970/44971 fqs=31 (t=10500 jiffies g=78121 q=238) rcu: rcu_preempt kthread timer wakeup didn't happen for 10431 jiffies! g78121 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=28884 rcu: rcu_preempt kthread starved for 10432 jiffies! g78121 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:28816 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4339 [inline] __schedule+0x916/0x23e0 kernel/sched/core.c:5147 schedule+0xcf/0x270 kernel/sched/core.c:5226 schedule_timeout+0x14a/0x250 kernel/time/timer.c:1892 rcu_gp_fqs_loop kernel/rcu/tree.c:2004 [inline] rcu_gp_kthread+0xd07/0x2300 kernel/rcu/tree.c:2177 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 243 Comm: kworker/u4:5 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:90 [inline] RIP: 0010:kvm_wait arch/x86/kernel/kvm.c:851 [inline] RIP: 0010:kvm_wait+0xb2/0x100 arch/x86/kernel/kvm.c:834 Code: 89 74 24 0c 48 89 3c 24 e8 7b 14 48 00 8b 74 24 0c 48 8b 3c 24 eb 82 e8 9c 19 48 00 e9 07 00 00 00 0f 00 2d 90 10 36 08 fb f4 98 e9 07 00 00 00 0f 00 2d 80 10 36 08 f4 eb bf 89 74 24 0c 48 RSP: 0018:ffffc900013df9f8 EFLAGS: 00000206 RAX: 0000000000c06aee RBX: 0000000000000000 RCX: 1ffffffff2052c9a RDX: 0000000000000000 RSI: 0000000000000201 RDI: 0000000000000000 RBP: ffff88806bfa92a8 R08: 0000000000000001 R09: ffffffff9023f987 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: ffffed100d7f5255 R14: 0000000000000001 R15: ffff8880b9d36000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005629ba190160 CR3: 000000005cb13000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pv_wait arch/x86/include/asm/paravirt.h:597 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline] __pv_queued_spin_lock_slowpath+0x8b8/0xb40 kernel/locking/qspinlock.c:508 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x200/0x2b0 kernel/locking/spinlock_debug.c:113 spin_lock_bh include/linux/spinlock.h:359 [inline] batadv_tt_local_commit_changes+0x1a/0x30 net/batman-adv/translation-table.c:3748 batadv_iv_ogm_schedule_buff+0x117e/0x1410 net/batman-adv/bat_iv_ogm.c:811 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:869 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:862 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x675/0x920 net/batman-adv/bat_iv_ogm.c:1723 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 NMI backtrace for cpu 0 CPU: 0 PID: 24411 Comm: syz-executor.3 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:341 print_cpu_stall kernel/rcu/tree_stall.h:624 [inline] check_cpu_stall kernel/rcu/tree_stall.h:699 [inline] rcu_pending kernel/rcu/tree.c:3911 [inline] rcu_sched_clock_irq.cold+0x3f1/0x74b kernel/rcu/tree.c:2649 update_process_times+0x16d/0x200 kernel/time/timer.c:1796 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1373 __run_hrtimer kernel/time/hrtimer.c:1537 [inline] __hrtimer_run_queues+0x1c0/0xe40 kernel/time/hrtimer.c:1601 hrtimer_interrupt+0x330/0xa00 kernel/time/hrtimer.c:1663 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline] __sysvec_apic_timer_interrupt+0x146/0x540 arch/x86/kernel/apic/apic.c:1106 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632 RIP: 0010:__local_bh_enable_ip+0xa8/0x120 kernel/softirq.c:391 Code: 1d 3d 1a bc 7e 65 8b 05 36 1a bc 7e a9 00 ff ff 00 74 45 bf 01 00 00 00 e8 05 11 09 00 e8 c0 f9 34 00 fb 65 8b 05 18 1a bc 7e <85> c0 74 58 5b 5d c3 65 8b 05 66 21 bc 7e 85 c0 75 a2 0f 0b eb 9e RSP: 0018:ffffc90002ccf8e8 EFLAGS: 00000202 RAX: 0000000000000201 RBX: 00000000fffffe00 RCX: 1ffffffff2052c9a RDX: 0000000000000000 RSI: 0000000000000201 RDI: 0000000000000000 RBP: ffffffff88b8cef7 R08: 0000000000000001 R09: ffffffff9023f987 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: ffff888027c1f788 R14: ffff88806bfa8c00 R15: dffffc0000000000 spin_unlock_bh include/linux/spinlock.h:399 [inline] batadv_tt_local_purge_pending_clients+0x347/0x460 net/batman-adv/translation-table.c:3704 batadv_tt_local_resize_to_mtu+0x96/0x130 net/batman-adv/translation-table.c:3988 batadv_update_min_mtu net/batman-adv/hard-interface.c:628 [inline] batadv_hard_if_event+0x67d/0x15b0 net/batman-adv/hard-interface.c:1020 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2121 call_netdevice_notifiers_mtu net/core/dev.c:2170 [inline] dev_set_mtu_ext+0x397/0x5a0 net/core/dev.c:8890 dev_set_mtu+0x8e/0x120 net/core/dev.c:8911 dev_ifsioc+0x49f/0xa60 net/core/dev_ioctl.c:261 dev_ioctl+0x1ad/0xb70 net/core/dev_ioctl.c:505 sock_do_ioctl+0x148/0x2d0 net/socket.c:1062 sock_ioctl+0x477/0x6a0 net/socket.c:1179 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665d9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f14139f3188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665d9 RDX: 00000000200000c0 RSI: 0000000000008922 RDI: 0000000000000006 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007fffbf6b23af R14: 00007f14139f3300 R15: 0000000000022000