rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10499 ticks this GP) idle=ee2/1/0x4000000000000002 softirq=10373/10373 fqs=2 
	(t=10501 jiffies g=6741 q=131)
rcu: rcu_preempt kthread starved for 10498 jiffies! g6741 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29032    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 0
CPU: 0 PID: 8277 Comm: syz-executor.3 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fb/0x318 lib/dump_stack.c:118
 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2827 [inline]
 rcu_sched_clock_irq+0xe25/0x1ad0 kernel/rcu/tree.c:2271
 update_process_times+0x12d/0x180 kernel/time/timer.c:1726
 tick_sched_handle kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1638
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:check_kcov_mode kernel/kcov.c:68 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x14/0x50 kernel/kcov.c:102
Code: 00 00 00 48 8b 3d 74 25 cd 07 48 89 de e8 64 02 3b 00 5b 5d c3 cc 48 8b 04 24 65 48 8b 0c 25 c0 1d 02 00 65 8b 15 b8 81 8b 7e <f7> c2 00 01 1f 00 75 2c 8b 91 80 13 00 00 83 fa 02 75 21 48 8b 91
RSP: 0018:ffffc90001ea6dc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: ffffffff81487326 RBX: ffffea00029b81c0 RCX: ffff88809f8bc000
RDX: 0000000000000001 RSI: 00000000fffffffc RDI: ffffea00029b81c0
RBP: ffffc90001ea6df0 R08: 000000000003a768 R09: ffffed10150c867f
R10: ffffed10150c867f R11: 0000000000000000 R12: ffff8880a38de520
R13: dffffc0000000000 R14: 00000000fffffffc R15: ffff8880a86433e8
 free_thread_stack+0x168/0x590 kernel/fork.c:280
 release_task_stack kernel/fork.c:440 [inline]
 put_task_stack+0xa3/0x130 kernel/fork.c:451
 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256
 context_switch kernel/sched/core.c:3388 [inline]
 __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081
 preempt_schedule_common kernel/sched/core.c:4236 [inline]
 preempt_schedule+0xdb/0x120 kernel/sched/core.c:4261
 ___preempt_schedule+0x16/0x18 arch/x86/entry/thunk_64.S:50
 __local_bh_enable_ip+0x17d/0x240 kernel/softirq.c:196
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline]
 _raw_spin_unlock_bh+0x2f/0x40 kernel/locking/spinlock.c:207
 spin_unlock_bh include/linux/spinlock.h:383 [inline]
 netif_addr_unlock_bh include/linux/netdevice.h:4097 [inline]
 __dev_mc_add+0x42a/0x540 net/core/dev_addr_lists.c:770
 dev_mc_add+0x1f/0x30 net/core/dev_addr_lists.c:783
 ip_mc_filter_add net/ipv4/igmp.c:1144 [inline]
 igmp_group_added+0x15c/0x830 net/ipv4/igmp.c:1330
 ____ip_mc_inc_group+0x943/0xb50 net/ipv4/igmp.c:1463
 __ip_mc_inc_group net/ipv4/igmp.c:1472 [inline]
 ip_mc_inc_group net/ipv4/igmp.c:1478 [inline]
 ip_mc_up+0x11c/0x2e0 net/ipv4/igmp.c:1777
 inetdev_event+0xe25/0x1350 net/ipv4/devinet.c:1573
 notifier_call_chain kernel/notifier.c:95 [inline]
 __raw_notifier_call_chain kernel/notifier.c:396 [inline]
 raw_notifier_call_chain+0xec/0x190 kernel/notifier.c:403
 __dev_notify_flags+0x24d/0x4d0 net/core/dev.c:1893
 dev_change_flags+0xec/0x190 net/core/dev.c:8179
 do_setlink+0xb2e/0x3960 net/core/rtnetlink.c:2589
 __rtnl_newlink net/core/rtnetlink.c:3236 [inline]
 rtnl_newlink+0x14dd/0x1bd0 net/core/rtnetlink.c:3361
 rtnetlink_rcv_msg+0x889/0xd40 net/core/rtnetlink.c:5422
 netlink_rcv_skb+0x19e/0x3d0 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5440
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x767/0x920 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0xa21/0xd40 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg net/socket.c:659 [inline]
 __sys_sendto+0x442/0x5e0 net/socket.c:1985
 __do_sys_sendto net/socket.c:1997 [inline]
 __se_sys_sendto net/socket.c:1993 [inline]
 __x64_sys_sendto+0xe5/0x100 net/socket.c:1993
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x414373
Code: ff 0f 83 b0 19 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d fd 40 66 00 00 75 17 49 89 ca b8 2c 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 81 19 00 00 c3 48 83 ec 08 e8 87 fa ff ff
RSP: 002b:00007ffc5e920758 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000a72200 RCX: 0000000000414373
RDX: 000000000000002c RSI: 0000000000a72250 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffc5e920760 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000a72250 R15: 0000000000000003