On Mon, Jul 30, 2012 at 04:54:34PM +0200, Martin Kletzander wrote: > On 07/30/2012 04:48 PM, Daniel P. Berrange wrote: > > On Mon, Jul 30, 2012 at 02:43:33PM +0200, Martin Kletzander wrote: > >> On 07/30/2012 02:33 PM, Daniel P. Berrange wrote: > >>> On Mon, Jul 30, 2012 at 02:25:04PM +0200, Martin Kletzander wrote: > >>>> There a two new elements in <features> implemented, which control what > >>>> ACPI sleeping states will be advertised. The default is to have both > >>>> states enabled, so this means no change for current machines. > >>> > >>>> diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng > >>>> index b7562ad..859cb26 100644 > >>>> --- a/docs/schemas/domaincommon.rng > >>>> +++ b/docs/schemas/domaincommon.rng > >>>> @@ -2788,6 +2788,16 @@ > >>>> <empty/> > >>>> </element> > >>>> </optional> > >>>> + <optional> > >>>> + <element name="disable_s3"> > >>>> + <empty/> > >>>> + </element> > >>>> + </optional> > >>>> + <optional> > >>>> + <element name="disable_s4"> > >>>> + <empty/> > >>>> + </element> > >>>> + </optional> > >>>> </interleave> > >>>> </element> > >>>> </optional> > >>> > >>> This is not very nice design. With this if an app wants to request > >>> S3, and have an error if it is not supported, they can't do that. > >>> > >> > >> I'm sorry, but I don't quite understand what do you mean. If the guest > >> wants to go to S3, there is (of course) no difference between the state > >> not being supported or the support being disabled. If an application > >> wants to request the guest to go to S3 through libvirt, then it will get > >> an appropriate message (disabled/not supported). Having one more option > >> means just setting the QEMU parameter to the default value (0). > > > > I'm talking about the host mgmt's POV. An application creating a guest > > may want to guarantee that S3 is available to the guest. With your > > proposal, there is no way they can do that - since there is no explicit > > element in the XML to request S3. So the mgmt app may get a guest with > > S3, or it may not - it has no way of being sure. The only thing a mgmt > > app can do is forcably disable S3 . > > > > Oh, yes, I get it now. Unfortunately, that is true. Sadly, the only > thing I see we can do with QEMU is set the disable_s[34] parameter(s) to > zero, but that won't guarantee anything, I guess. Global parameters are > valid even if they don't make sense or they don't exist, so even > "qemu-kvm -global a.s=df" is a valid command-line. Well regardless, that is a QEMU bug - please report it to the QEMU developer mailing list. libvirt needs to find a way to detct whether S3 is available and report CONFIG_NOT_SUPPORTED, even if we just do this based on version number. Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :| -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list