[Pkg-xen-devel] Bug#879751: xen-utils-common: /etc/init.d/xen restart kills running domU qemu processes

[Hans van Kranenburg]

Hi Richard,

it's recommended to only actually upgrade xen packages just before you
want to reboot the system, and when you already stopped all domUs.

This is e.g. a similar situation to upgrading the openvswitch package,
which will also restart processes and mess up all network interfaces of
running domUs.

For unattended-updates, you can just stuff "xen" inside your
Unattended-Upgrade::Package-Blacklist, or if you're not using that you
can put all xen related packages on hold manually and only forcibly
include them to be upgraded just before the reboot.

Upgrading the xen packages while domUs are running can result in a wide
range of scenarios which will cause problems. Solving all of those would
require more work and adding far more complexity to the packages than
there's programmers and testers (and hardware to test all scenarios etc)
available in the Debian project to make that happen currently.

Hans