We had the same behaviour like Dennis! Kernel Panic after aprox. 4 our on kernel 4.4.0-184 Unbound installed as well with version 1.5.8 Unfortunately i have no crashdump by hand, but our panic was "same" as Dennis with ipv6 messages.
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1883498 Title: Frequent Panic in ip6_expire_frag_queue->icmpv6_send on 4.4.0-184-generic Status in linux package in Ubuntu: Confirmed Bug description: I happened to do an upgrade on a number of servers last week. Some of them got 4.4.0-179-generic and the ones upgraded a bit later during the week got 4.4.0-184-generic as it was just released. The ones with 4.4.0-184-generic started getting stuck. With linux-crashdump installed I obtained the dmesgs and crash dumps. The backtrace appears somewhat similar to #202669 but that one only happened on bare hardware for us - this one is on KVM virtual instances. #202669 paniced in icmpv6_route_lookup and this one dies already in icmpv6_send. Between 2020-06-11 and 2020-06-15, on a set of 12 VMs running 4.4.0-184-generic, there were 85 crashes like this, on servers with noticeable IPv6 traffic. All of the 12 VMs with 4.4.0-184-generic crashed at least once. (There are more than 12 VMs experiencing this, this is just the set I had linux-crashdump on.) [57063.487084] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 [57063.487184] IP: [<ffffffff818288ab>] icmp6_send+0x1fb/0x970 [57063.487218] PGD 0 [57063.487231] Oops: 0000 [#1] SMP [57063.488665] Call Trace: [57063.488679] <IRQ> [57063.488705] [<ffffffff81756ee8>] ? __netif_receive_skb+0x18/0x60 [57063.488739] [<ffffffff810c3758>] ? task_tick_fair+0x4c8/0x8e0 [57063.488771] [<ffffffff81868280>] ? _raw_spin_unlock_bh+0x20/0x50 [57063.488802] [<ffffffff81841ed1>] icmpv6_send+0x21/0x30 [57063.488829] [<ffffffff8182fe95>] ip6_expire_frag_queue+0x115/0x1b0 [57063.488862] [<ffffffffc0366260>] ? nf_ct_net_exit+0x50/0x50 [nf_defrag_ipv6] [57063.488897] [<ffffffffc036627f>] nf_ct_frag6_expire+0x1f/0x30 [nf_defrag_ipv6] [57063.488937] [<ffffffff810f57c7>] call_timer_fn+0x37/0x140 [57063.488965] [<ffffffffc0366260>] ? nf_ct_net_exit+0x50/0x50 [nf_defrag_ipv6] [57063.489002] [<ffffffff810f70d4>] run_timer_softirq+0x234/0x330 ... To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1883498/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp