[CentOS] CentOS 7.4 fails to boot as Xen PV guest: resurfaces (now also) with centosplus kernel 693.11.6.el7

Mon Jan 8 06:38:05 UTC 2018
Akemi Yagi <amyagi at gmail.com>

On Sun, Jan 7, 2018 at 12:07 PM, David Groep <davidg at nikhef.nl> wrote:

> Dear all,
>
> Maybe I'm the only one - so before filing it as a bug: it appears that
> the latest set of kernel patches in 3.10.0-693.11.6.el7 makes issue
> 0013763 "CentOS 7.4 kernel (3.10.0-693*) fails to boot as Xen PV guest"
> re-surface *also* with the CentOS PLUS kernel. But maybe in a
> different way ...
>
> Thanks to the (great!) quick work on making the plus kernel available
> (in #14330, thanks for that!) I was able to test the following
> combinations:
>
> - 3.10.0-693.11.6.el7.centos.plus works fine on XenServer 7 HVM guests
> - 3.10.0-693.11.1.el7.centos.plus works fine on XenServer 7 XenPV guests
> - 3.10.0-693.11.6.el7.centos.plus crashes on boot for XS7 XenPV guests
>   immediately after the boot stage where the PS/2 drivers are loaded
>
> Crashing does not depend on the amount of VM memory or #cores/sockets.
> Also, the tell-tale "mm/vmalloc.c" failure output is no longer present.
> The system 'just' crashes (with the kernel log lines as below) around the
> time of the i8042 controller probing.
>
> Obviously the stock upstream 3.10.0-693.11.6.el7 crashes as well for
> XS7 XenPV guests, but that was to be expected as per 0013763.
> It crashes in the same way, around the time of the i8042 probes.
>
> Can anyone (maybe bill_mcgonigle?) reproduce the issue?
> Did the KPTI patches break the XenPV fixes in CentOS Plus per 13763?
> Or is this a new XenPV issue?
>

​You may want to be watching the centos-virt mailing list. Xen-related
issues are discussed there.

This thread:

​
https://lists.centos.org/pipermail/centos-virt/2018-January/005716.html

​has a response from Johnny Hughes with a possible solution.

Akemi​