Out of the IRC discussions documenting potentially related issues: - this bug: KVM: Host-Kernel: Xenial-GA, Qemu: Xenial-Ocata, Guest: Bionic - bug 1722311 KVM: Host-Kernel: Xenial-GA, Qemu: Xenial, Guest: Artful - some relation to cache pressure - bug 1713751 AWS: triggered by Xenial kernel update, supposed fixed but shown up again and again - bug 1655842 Host-Kernel: Xenial-GA, Qemu: Xenial, Guest: Artful - some relation to cache pressure These might after all just run into the same soft lockup symptom, but I thought it was worth to mention for thos enot reading the IRC log.
These cases seem to somewhat agree on: - Recent guest kernel - Xenial Host kernel - some memory pressure To get further I thought some sort of local reproducer for the kernel Team to work on easier than needing a full cloud. But so far I failed at setting such a local case up (http://paste.ubuntu.com/25916781/). Thanks Laney for the openstack based repro description. @Laney I found it interesting that you essentially only needed to start+reboot. I assume on the host you had other workload goes on in the background (since it is lcy01)? If you'd have any sort of non-busy but otherwise comparable system - could you check to confirm the assumption we have so far that there all is fine? If yes - then the memory pressure theory gets more likely, if not we can focus on simpler reproducers - so we can only win by that check. Crossing fingers for jsalisbury's hope that 4.14 might already have a fix. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1730717 Title: Some VMs fail to reboot with "watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [systemd:1]" To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1730717/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
