rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10500 ticks this GP) idle=2d6/1/0x4000000000000004 softirq=10480/10480 fqs=0 (t=10500 jiffies g=8721 q=2114) rcu: rcu_preempt kthread starved for 10500 jiffies! g8721 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt I29440 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3254 [inline] __schedule+0x755/0x1580 kernel/sched/core.c:3880 schedule+0xd9/0x260 kernel/sched/core.c:3947 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1807 rcu_gp_fqs_loop kernel/rcu/tree.c:1611 [inline] rcu_gp_kthread+0x9b2/0x18c0 kernel/rcu/tree.c:1768 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 1 CPU: 1 PID: 9031 Comm: syz-executor.3 Not tainted 5.3.0-rc7+ #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+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x183/0x1cf 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:2736 [inline] rcu_sched_clock_irq.cold+0x4dd/0xc13 kernel/rcu/tree.c:2183 update_process_times+0x32/0x80 kernel/time/timer.c:1639 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1296 __run_hrtimer kernel/time/hrtimer.c:1389 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1451 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1106 [inline] smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1131 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:__list_add include/linux/list.h:65 [inline] RIP: 0010:list_add_tail include/linux/list.h:93 [inline] RIP: 0010:list_move_tail include/linux/list.h:214 [inline] RIP: 0010:hhf_dequeue+0x6cd/0xa20 net/sched/sch_hhf.c:439 Code: 98 03 00 00 48 c1 e8 03 42 80 3c 20 00 0f 85 b4 02 00 00 48 8b 45 c8 48 8d 7b 08 48 89 03 48 89 f8 48 c1 e8 03 42 80 3c 20 00 <0f> 85 8d 02 00 00 4c 89 f8 4c 89 7b 08 48 c1 e8 03 42 80 3c 20 00 RSP: 0018:ffff8880ae9095c8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 1ffff110143fa588 RBX: ffff8880a1fd2c38 RCX: ffffffff85c7e179 RDX: 0000000000000100 RSI: ffffffff85c7e18b RDI: ffff8880a1fd2c40 RBP: ffff8880ae909618 R08: ffff8880919ee280 R09: fffffbfff14e9555 R10: ffff8880919eec28 R11: ffff8880919ee280 R12: dffffc0000000000 R13: ffff8880a1fd2940 R14: ffff8880a1fd2cd8 R15: ffff8880a1fd2cd0 dequeue_skb net/sched/sch_generic.c:258 [inline] qdisc_restart net/sched/sch_generic.c:361 [inline] __qdisc_run+0x1e7/0x19d0 net/sched/sch_generic.c:379 __dev_xmit_skb net/core/dev.c:3533 [inline] __dev_queue_xmit+0x16f1/0x3650 net/core/dev.c:3838 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902 neigh_hh_output include/net/neighbour.h:500 [inline] neigh_output include/net/neighbour.h:509 [inline] ip6_finish_output2+0xf58/0x2520 net/ipv6/ip6_output.c:116 __ip6_finish_output+0x444/0xa50 net/ipv6/ip6_output.c:142 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip6_output+0x235/0x7c0 net/ipv6/ip6_output.c:175 dst_output include/net/dst.h:436 [inline] NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] mld_sendpack+0x9c7/0xea0 net/ipv6/mcast.c:1682 mld_send_initial_cr.part.0+0x114/0x160 net/ipv6/mcast.c:2099 mld_send_initial_cr net/ipv6/mcast.c:2083 [inline] mld_dad_timer_expire+0x42/0x1c0 net/ipv6/mcast.c:2118 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322 expire_timers kernel/time/timer.c:1366 [inline] __run_timers kernel/time/timer.c:1685 [inline] __run_timers kernel/time/timer.c:1653 [inline] run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:537 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1133 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:67 Code: 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01 RSP: 0018:ffff8880638dfba0 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13 RAX: 1ffff1101259ff00 RBX: ffffed101259ff08 RCX: 0000000000000000 RDX: 0000000000000024 RSI: 0000000000000000 RDI: ffffed101259ff08 RBP: ffff8880638dfbb8 R08: 1ffffffff14e9550 R09: ffffed101259fee4 R10: fffffbfff14e9550 R11: ffffffff8a74aa87 R12: 0000000000000120 R13: ffff888092cff720 R14: ffff888092cff83f R15: ffff88809b617540 __kasan_kmalloc.constprop.0+0x4c/0xe0 mm/kasan/common.c:488 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:501 slab_post_alloc_hook mm/slab.h:520 [inline] slab_alloc mm/slab.c:3319 [inline] kmem_cache_alloc+0x121/0x710 mm/slab.c:3483 __d_alloc+0x2e/0x8c0 fs/dcache.c:1688 d_alloc+0x4d/0x280 fs/dcache.c:1767 __lookup_hash+0xcd/0x190 fs/namei.c:1540 filename_create+0x1a7/0x4f0 fs/namei.c:3635 user_path_create fs/namei.c:3692 [inline] do_symlinkat+0xf3/0x290 fs/namei.c:4147 __do_sys_symlink fs/namei.c:4173 [inline] __se_sys_symlink fs/namei.c:4171 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4171 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459617 Code: 0f 1f 00 b8 5c 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 bd ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 58 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 9d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffdc4555c38 EFLAGS: 00000202 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000459617 RDX: 00007ffdc4555cd3 RSI: 00000000004bf132 RDI: 00007ffdc4555cc0 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000013 R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000001 R13: 00007ffdc4555c70 R14: 0000000000000000 R15: 00007ffdc4555c80