[systemd-devel] [PATCH] systemd-detect-s390-virt: add virtualization detection on s390x

[Lennart Poettering]

On Mon, 07.07.14 16:37, Thomas Blume (Thomas.Blume at suse.com) wrote:

> 
> On Mon, 7 Jul 2014, Lennart Poettering wrote:
> 
> >>For the test, e.g. ConditionVirtualization, there would be no difference.
> >>I only distinguished this in order to have systemd-detect-virt showing the
> >>correct virtualization technology.
> >>Sure we could cover everything under something like, e.g. "s390 virtualization".
> >>But I thought it is smarter to give this little additional information.
> >>Maybe there are some cases where someone needs to know in more detail which
> >>virtualization is running.
> >
> >Again, what precisely is the difference between the two virtualizations you
> >wanted to distinguish?
> 
> IMHO the main difference is the level of maturity.
> z/VM is about 30 years old and has a huge amount of tools for everything you
> could imagine. KVM is relatively new and under heavy development.
> Furthermore, KVM is bound to the linux kernel, while z/VM is not.
> Finally, KVM could theoretically run inside z/VM (thought it doesn't make sense
> running KVM on an already virtualized CPU) but not vice-versa.
> 
> Kay, my colleague Ihno told me that you were working in the s390 department at SUSE.
> Any opinion about the use of distinguishing z/VM from KVM under s390?

Well, obviously, we should distuingish kvm from some s390-specific
virtualization. I was mostly referring to your original's patch
distinction between "PR/SM" and "z/VM". What is that about?

Lennart

-- 
Lennart Poettering, Red Hat