On Oct 16, 2013, at 9:02 AM, Eric Blake <eblake(a)redhat.com> wrote:
On 10/16/2013 08:12 AM, Chris Murphy wrote:
> Is a 64bit host expected to support running a 32bit guest OS in qemu/kvm? Or do archs
need to match?
64-bit guets on 64-bit host exposing a 64-bit environment - works just
fine; supported, uses hardware acceleration.
32-bit guest on 64-bit host exposing only a 32-bit environment - works
just fine; supported, uses hardware acceleration.
32-bit guest on 64-bit host exposing a 64-bit environment - works just
fine; supported, uses hardware acceleration.
32-bit guest on 32-bit host (necessarily exposing a 32-bit environment)
- works just fine; supported, uses hardware acceleration (but gets less
testing, as few people run virt hosts in 32-bit mode).
No support for running a 64-bit guest on a 32-bit host (hardware just
doesn't expose enough memory).
OK thanks. Followups are:
Q1: Where in virt-manager is the setting to expose 32bit/64bit environment? I don't
see this in Processor. I do see Architecture: x86_64 in Overview>Hypervisor Details but
I have no way to change it.
Q2: Should this test case:
https://fedoraproject.org/wiki/QA:Testcase_Install_to_Current_KVM
Cover all of the above combinations, minus 64-bit guest on 32-bit host? Or is 64/64, and
either 64/32 or 32/32 sufficient?
Chris Murphy