On 23.09.2019 10:17, Jan Beulich wrote:
>>> Does booting with a single vCPU work?
>> Number of vCPUs make no difference
> Well, according to Steven it does, with viridian=0. Could you
> re-check this?

I can confirm that viridian=0 AND vcpus=1 makes the system bootable 
(with long delay though)

> at least the viridian=0 case? As to Linux, did you check that PVH
> (or HVM, which you don't mention) guests actually start all their vCPU-s
> successfully?

I just tried PVH and HVM with 8 vcpus. Everything works, tested with 
make -j9 on a kernel tree.

 > 8-core chip, I wonder whether
 > 
https://lists.xenproject.org/archives/html/xen-devel/2019-09/msg01954.html
 > still affects this configuration as well. Could you give this a try in

Does it still make sense to try the patch given the cpuid I posted?
Also I have an AMD 7302P in my lab (cpuid dump attached). No change in 
behavior from 3700X - cpuid is nearly the same.

Regards Andreas