------- Comment From dieg...@br.ibm.com 2017-11-27 06:16 EDT------- (In reply to comment #11) > The problem seems to be related to how qemu allocates the virtual cores and > threads to the VM. > > Starting the VMs with the following command I cannot reproduce the issue: > > $ qemu-system-ppc64le -m 1024 -smp 16,threads=8 -nographic -net > nic,model=virtio -net user,hostfwd=tcp::10022-:22 -drive > file=./autopkgtest-xenial-ppc64el.img -enable-kvm > > As long the number of cpus and threads provided to the -smp parameter follow > the topology of the p8 processor, making qemu use more than one core only if > the number of threads is multiple of 8, I can't reproduce the hang. If the > parameters provided makes qemu spread the virtual threads on more than one > physical cpu without using all the 8 threads (e.g. '-smp 2', '-smp > 4,threads=2', '-smp 8,threads=4') then the guest kernel hangs at some point. > > This is the environment being tested: > > Machine type-model: 8247-22L > > Host: Artful > kernel 4.13.0-17-generic > qemu 2.10+dfsg-0ubuntu3 > > Guests: Xenial, Zesty and Artful with latest kernel from -updates. > > Could someone from IBM please confirm if this is a known or expected > behavior? This issue seems to be around for a long time and it's odd that > this hasn't come up before.
I was not able to reproduce this issue with the following command and environment: $ /usr/libexec/qemu-kvm -hda /home/libvirt-images/diegodo/diegodo- ubuntu16.qcow2 -boot c -net nic -net user -m 512 -localtime -nographic -smp 4,threads=2 HOST: Rhel 7.3 kernel: 4.13.0-rc4 qemu: 2.6.0 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1733864 Title: kernel 4.10.0-40 is hanging with a CPU soft lock To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1733864/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
