rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=87e/1/0x4000000000000000 softirq=8966/8967 fqs=47 (t=10502 jiffies g=10741 q=91) rcu: rcu_preempt kthread starved for 10409 jiffies! g10741 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:29080 pid: 10 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_timeout+0x148/0x250 kernel/time/timer.c:1879 rcu_gp_fqs_loop kernel/rcu/tree.c:1888 [inline] rcu_gp_kthread+0xae5/0x1b50 kernel/rcu/tree.c:2058 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 NMI backtrace for cpu 1 CPU: 1 PID: 8223 Comm: syz-executor.2 Not tainted 5.9.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x194/0x1cf kernel/rcu/tree_stall.h:318 print_cpu_stall kernel/rcu/tree_stall.h:551 [inline] check_cpu_stall kernel/rcu/tree_stall.h:625 [inline] rcu_pending kernel/rcu/tree.c:3637 [inline] rcu_sched_clock_irq.cold+0x5b3/0xccd kernel/rcu/tree.c:2519 update_process_times+0x25/0xa0 kernel/time/timer.c:1710 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176 tick_sched_timer+0x1d1/0x2a0 kernel/time/tick-sched.c:1328 __run_hrtimer kernel/time/hrtimer.c:1524 [inline] __hrtimer_run_queues+0x1d5/0xfc0 kernel/time/hrtimer.c:1588 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1650 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline] __sysvec_apic_timer_interrupt+0x142/0x5e0 arch/x86/kernel/apic/apic.c:1097 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] sysvec_apic_timer_interrupt+0xb2/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:102 [inline] RIP: 0010:__local_bh_enable_ip+0x101/0x190 kernel/softirq.c:202 Code: 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 8b 00 00 00 48 83 3d b0 5c 6f 08 00 74 2f fb 66 0f 1f 44 00 00 <65> 8b 05 48 1f bb 7e 85 c0 74 46 5b 5d c3 0f 0b e9 4a ff ff ff 48 RSP: 0018:ffffc9000a20ed50 EFLAGS: 00000286 RAX: 1ffffffff136c77b RBX: 0000000000000201 RCX: 0000000000000002 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff8146df01 RBP: ffffffff87d849d5 R08: 0000000000000001 R09: ffffffff8c5e5ad7 R10: fffffbfff18bcb5a R11: 0000000032323854 R12: 0000000000000100 R13: ffff88808b9ba498 R14: 000000000000029c R15: dffffc0000000000 spin_unlock_bh include/linux/spinlock.h:399 [inline] batadv_tt_local_purge+0x285/0x370 net/batman-adv/translation-table.c:1446 batadv_tt_local_resize_to_mtu+0x8e/0x130 net/batman-adv/translation-table.c:4197 batadv_hardif_activate_interface.part.0.cold+0x14c/0x1ba net/batman-adv/hard-interface.c:653 batadv_hardif_activate_interface net/batman-adv/hard-interface.c:800 [inline] batadv_hardif_enable_interface+0xa7d/0xb10 net/batman-adv/hard-interface.c:792 batadv_softif_slave_add+0x92/0x150 net/batman-adv/soft-interface.c:892 do_set_master+0x1c8/0x220 net/core/rtnetlink.c:2517 do_setlink+0x911/0x3a70 net/core/rtnetlink.c:2713 __rtnl_newlink+0xc1c/0x1740 net/core/rtnetlink.c:3374 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3500 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5563 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2353 ___sys_sendmsg+0xf3/0x170 net/socket.c:2407 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2440 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c369 Code: 8d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f1079353c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000002b740 RCX: 000000000045c369 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000004 RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c R13: 00007ffca6efd32f R14: 00007f10793549c0 R15: 000000000078bf0c