[libvirt] Problem setting CPU topology

[Zeeshan Ali (Khattak)]

On Sun, Jul 8, 2012 at 1:36 AM, Doug Goldstein <cardoe at gentoo.org> wrote:
> On Sat, Jul 7, 2012 at 11:10 AM, Zeeshan Ali (Khattak)
> <zeeshanak at gnome.org> wrote:
>> Hi,
>>    I'm trying to set exact CPU topology to qemu-kvm domains to match
>> host's topology. In my case, host topology is: 1 socket, 2 cores and 2
>> threads. If I set the XML like this:
>
> <snip>
>
>> The qemu commandline launched for this domain looks like this:
>>
>> /usr/bin/qemu-kvm -name fedora17-2 -S -M pc-0.15 -cpu
>> core2duo,+lahf_lm,+rdtscp,+aes,+popcnt,+sse4.2,+sse4.1,+pdcm,+xtpr,+cx16,+tm2,+est,+smx,+vmx,+ds_cpl,+dtes64,+pclmuldq,+pbe,+tm,+ht,+ss,+acpi,+ds
>> -enable-kvm -m 1152 -smp 4,sockets=1,cores=2,threads=2 -uuid
>
> <snip>
>
>>
>> Despite the '-smp 4,sockets=1,cores=2,threads=2', I see only 1 CPU
>> reported by '/proc/cpuinfo' in the guest F17 live.
>>
>> However, when I manually launch a very similar commandline,':
>>
>> /usr/bin/qemu-kvm -name fedora17-2 -M pc-0.15 -cpu
>> core2duo,+lahf_lm,+rdtscp,+aes,+popcnt,+sse4.2,+sse4.1,+pdcm,+xtpr,+cx16,+tm2,+est,+smx,+vmx,+ds_cpl,+dtes64,+pclmuldq,+pbe,+tm,+ht,+ss,+acpi,+ds
>> -m 1G -smp 4,cores=2,threads=2,sockets=1 -uuid
>> c573342b-2876-05b8-098e-6d5314cab062 -nodefconfig -enable-kvm -cdrom
>> /home/zeenix/ISOs/Fedora-17-i686-Live-Desktop.iso
>>
>> I see 4 CPUs reported by '/proc/cpuinfo in the guest. Any clues?
>
> What version of qemu-kvm are you using? Sounds like a bug in
> qemu-kvm's command line arg parsing code.

I was able to reproduce this with both qemu from git master and
qemu-kvm from stock F17 packages (1.0).

-- 
Regards,

Zeeshan Ali (Khattak)
FSF member#5124