[CentOS] Panic with EL7 KVM guest on EL6 host on AMD server with latest kernel

Mon Jul 16 15:19:51 UTC 2018
Simon Matter <simon.matter at invoca.ch>


I have AMD servers running CentOS 6.10 as KVM host and on it guests
running CentOS 7.5.

Since the latest kernel update on CentOS 6.10,
kernel-2.6.32-754.2.1.el6.x86_64, I can't boot the CentOS 7.5 guests with
kernel-3.10.0-862.6.3.el7.x86_64 anymore.

Reverting CentOS 6.10 host to kernel-2.6.32-754.el6.x86_64 fixes the problem.

Screendump of the panic is attached, not very helpful I guess.

The CPU models where I could test it are:

cpu family	: 15
model		: 65
model name	: Dual-Core AMD Opteron(tm) Processor 2218
stepping	: 3

cpu family      : 16
model           : 6
model name      : AMD Athlon(tm) II Neo N36L Dual-Core Processor
stepping        : 3

Didn't test on newer CPU family yet.

I'm wondering, does someone see the same issue? Does it not happen on
Intel CPUs?

Thanks for any insight.