rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (1 GPs behind) idle=6da/1/0x4000000000000000 softirq=11454/11456 fqs=5246 (t=10502 jiffies g=12845 q=1409) NMI backtrace for cpu 0 CPU: 0 PID: 9932 Comm: syz-executor.1 Not tainted 5.14.0-rc5-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:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 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:342 print_cpu_stall kernel/rcu/tree_stall.h:625 [inline] check_cpu_stall kernel/rcu/tree_stall.h:700 [inline] rcu_pending kernel/rcu/tree.c:3922 [inline] rcu_sched_clock_irq.cold+0x9f/0x747 kernel/rcu/tree.c:2641 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1537 [inline] __hrtimer_run_queues+0x1c0/0xe50 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+0x146/0x530 arch/x86/kernel/apic/apic.c:1106 sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:unwind_next_frame+0xd82/0x1ce0 arch/x86/kernel/unwind_orc.c:580 Code: b6 04 02 4c 89 ea 83 e2 07 38 d0 7f 08 84 c0 0f 85 e1 0d 00 00 4c 89 fa 41 c6 46 35 00 48 89 ce 48 b8 00 00 00 00 00 fc ff df <48> c1 ea 03 48 c1 ee 03 0f b6 14 02 0f b6 04 06 4c 89 fe 83 e6 07 RSP: 0018:ffffc90000006848 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: 1ffff92000000d11 RCX: ffffffff8de6fbe5 RDX: ffffffff8de6fbe4 RSI: ffffffff8de6fbe5 RDI: ffffc90000006978 RBP: 0000000000000002 R08: ffffffff8de6fbe0 R09: ffffffff8de6fbda R10: fffff52000000d2f R11: 0000000000086088 R12: ffffc9000aa06860 R13: ffffc90000006955 R14: ffffc90000006920 R15: ffffffff8de6fbe4 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1625 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1650 slab_free mm/slub.c:3210 [inline] kfree+0xe4/0x530 mm/slub.c:4264 skb_free_head net/core/skbuff.c:654 [inline] skb_release_data+0x65a/0x790 net/core/skbuff.c:676 skb_release_all net/core/skbuff.c:741 [inline] __kfree_skb net/core/skbuff.c:755 [inline] kfree_skb net/core/skbuff.c:773 [inline] kfree_skb+0x133/0x3f0 net/core/skbuff.c:767 enqueue_to_backlog+0x210/0x10b0 net/core/dev.c:4732 netif_rx_internal+0x120/0x640 net/core/dev.c:4963 netif_rx+0x7f/0x510 net/core/dev.c:4990 loopback_xmit+0x222/0x630 drivers/net/loopback.c:88 __netdev_start_xmit include/linux/netdevice.h:4944 [inline] netdev_start_xmit include/linux/netdevice.h:4958 [inline] xmit_one net/core/dev.c:3659 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3675 __dev_queue_xmit+0x2988/0x3620 net/core/dev.c:4285 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip_finish_output2+0xef0/0x2220 net/ipv4/ip_output.c:230 ip_do_fragment+0x6f2/0x1450 net/ipv4/ip_output.c:914 ip_fragment.constprop.0+0x174/0x240 net/ipv4/ip_output.c:582 __ip_finish_output net/ipv4/ip_output.c:306 [inline] __ip_finish_output+0x2de/0x640 net/ipv4/ip_output.c:290 ip_finish_output+0x32/0x200 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip_output+0x196/0x310 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:448 [inline] ip_local_out+0xaf/0x1a0 net/ipv4/ip_output.c:126 iptunnel_xmit+0x5a3/0x9c0 net/ipv4/ip_tunnel_core.c:82 geneve_xmit_skb drivers/net/geneve.c:971 [inline] geneve_xmit+0x10e2/0x3540 drivers/net/geneve.c:1082 __netdev_start_xmit include/linux/netdevice.h:4944 [inline] netdev_start_xmit include/linux/netdevice.h:4958 [inline] xmit_one net/core/dev.c:3659 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3675 __dev_queue_xmit+0x2988/0x3620 net/core/dev.c:4285 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip6_finish_output2+0x974/0x19d0 net/ipv6/ip6_output.c:145 __ip6_finish_output net/ipv6/ip6_output.c:210 [inline] __ip6_finish_output+0x4c1/0x1050 net/ipv6/ip6_output.c:189 ip6_finish_output+0x32/0x200 net/ipv6/ip6_output.c:220 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:243 dst_output include/net/dst.h:448 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ndisc_send_skb+0xa99/0x1750 net/ipv6/ndisc.c:508 ndisc_send_rs+0x12e/0x6f0 net/ipv6/ndisc.c:702 addrconf_rs_timer+0x3f2/0x820 net/ipv6/addrconf.c:3877 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 do_softirq.part.0+0xde/0x130 kernel/softirq.c:459 </IRQ> do_softirq kernel/softirq.c:451 [inline] __local_bh_enable_ip+0x102/0x120 kernel/softirq.c:383 fib_table_delete+0x78b/0xa40 net/ipv4/fib_trie.c:1762 fib_magic+0x321/0x540 net/ipv4/fib_frontend.c:1089 fib_del_ifaddr+0xf1a/0x13c0 net/ipv4/fib_frontend.c:1288 fib_inetaddr_event+0xb4/0x2a0 net/ipv4/fib_frontend.c:1428 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 blocking_notifier_call_chain kernel/notifier.c:337 [inline] blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:325 __inet_del_ifa+0x415/0xf70 net/ipv4/devinet.c:428 inet_del_ifa net/ipv4/devinet.c:465 [inline] inetdev_destroy net/ipv4/devinet.c:318 [inline] inetdev_event+0x671/0x15d0 net/ipv4/devinet.c:1598 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2123 call_netdevice_notifiers_mtu net/core/dev.c:2172 [inline] dev_set_mtu_ext+0x397/0x5a0 net/core/dev.c:8964 do_setlink+0x57e/0x3900 net/core/rtnetlink.c:2684 rtnl_group_changelink net/core/rtnetlink.c:3244 [inline] __rtnl_newlink+0xbf5/0x1760 net/core/rtnetlink.c:3398 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3508 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5574 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:703 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:723 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2392 ___sys_sendmsg+0xf3/0x170 net/socket.c:2446 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2475 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 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:00007f68e9796188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665e9 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000006 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007ffc3dd6775f R14: 00007f68e9796300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: b6 04 mov $0x4,%dh 2: 02 4c 89 ea add -0x16(%rcx,%rcx,4),%cl 6: 83 e2 07 and $0x7,%edx 9: 38 d0 cmp %dl,%al b: 7f 08 jg 0x15 d: 84 c0 test %al,%al f: 0f 85 e1 0d 00 00 jne 0xdf6 15: 4c 89 fa mov %r15,%rdx 18: 41 c6 46 35 00 movb $0x0,0x35(%r14) 1d: 48 89 ce mov %rcx,%rsi 20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 27: fc ff df 2a: 48 c1 ea 03 shr $0x3,%rdx <-- trapping instruction 2e: 48 c1 ee 03 shr $0x3,%rsi 32: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx 36: 0f b6 04 06 movzbl (%rsi,%rax,1),%eax 3a: 4c 89 fe mov %r15,%rsi 3d: 83 e6 07 and $0x7,%esi