group.of.nepali.translators team mailing list archive

[Launchpad Bug Tracker <1783140@xxxxxxxxxxxxxxxxxx>]

This bug was fixed in the package qemu - 1:2.5+dfsg-5ubuntu10.32

---------------
qemu (1:2.5+dfsg-5ubuntu10.32) xenial; urgency=medium

  * fix migration of new guests on ppc64el (LP: #1783140)
    Fixed by backporting two patches from the 2.6.x stable branch
    - d/p/ubuntu/lp-1783140-virtio-set-low-features-early-on-load.patch
    - d/p/ubuntu/lp-1783140-Revert-virtio-net-unbreak-self-announcement.patch

 -- Christian Ehrhardt <christian.ehrhardt@xxxxxxxxxxxxx>  Tue, 11 Sep
2018 15:00:19 +0200

** Changed in: qemu (Ubuntu Xenial)
       Status: Fix Committed => Fix Released

-- 
You received this bug notification because you are a member of नेपाली
भाषा समायोजकहरुको समूह, which is subscribed to Xenial.
Matching subscriptions: Ubuntu 16.04 Bugs
https://bugs.launchpad.net/bugs/1783140

Title:
  KVM live migration fails

Status in The Ubuntu-power-systems project:
  In Progress
Status in linux package in Ubuntu:
  Triaged
Status in qemu package in Ubuntu:
  Fix Released
Status in qemu source package in Xenial:
  Fix Released

Bug description:
  [Impact]

   * Backport fix from the 2.6.2 stable branch to the qemu 2.5 in Xenial

   * Newer guests might use virtio attributes that are clobbered on 
     migration with the old qemu code.

  [Test Case]

   * Setup two Xenial hosts on ppc64el

   * Create a guest that has a rather new kernel (>=4.14) I'd recommend 
     Bionic

   * Migrate that guest from Host1 to Host2

  [Regression Potential]

   * The modification could affect virtio handling in other cases in a non 
     expected way, but mostly related to migrations. So the expected 
     regression would be issues to migrate properly.
     I verified plenty of migrations in regression testing and we had
     this very code in the Yakkety release as we picked 2.6.1 stable release 
     back then. Due to that it is actually pretty well tested and should not 
     really regress anything out in the wild.

  [Other Info]
   
   * So far this only triggers on the confused endian marshalling on 
     ppc64el, but in theory a different case could trigger it on x86 just as 
     much.

  ---

  Environment:
  2 POWER8 with Ubuntu 16.04.4 LTS as KVM hypervisor.
  1 KVM guest with Ubuntu 18.04 LTS. Virtual disk for the guest is a qcow2 file on an NFS share, accessible from both hypervisors, so live migration is possible and works for all other guests (SLES, RHEL, Ubunutu 16.04),
  Live migratino of Ubuntu 18.04 guest fails on ppc, while the same test on an x86_64 environment suceeds.

  root@pkvm2:~# virsh migrate --persistent --live p8lnxtst4 qemu+ssh://pkvm1/system
  error: internal error: early end of file from monitor, possible problem: 2018-07-23T11:12:25.586385Z qemu-system-ppc64: VQ 0 size 0x100 Guest index 0x38aa inconsistent with Host index 0xa980: delta 0x8f2a
  2018-07-23T11:12:25.586434Z qemu-system-ppc64: error while loading state for instance 0x0 of device 'pci@800000020000000:01.0/virtio-net'
  2018-07-23T11:12:25.587246Z qemu-system-ppc64: load of migration failed: Operation not permitted

  root@pkvm2:~# uname -a
  Linux pkvm2 4.4.0-130-generic #156-Ubuntu SMP Thu Jun 14 08:51:21 UTC 2018 ppc64le ppc64le ppc64le GNU/Linux

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu-power-systems/+bug/1783140/+subscriptions