Re: [Qemu-devel] [PATCH] pc_piix: enable legacy hotplug for Xen

[Stefano Stabellini]

On Tue, 4 Feb 2014, Paolo Bonzini wrote:
> Il 04/02/2014 22:32, Michael S. Tsirkin ha scritto:
> > xenfv has no fwcfg and so does not load acpi from QEMU.
> > as such new acpi features don't work.
> > 
> > Reported-by: Sander Eikelenboom <address@hidden>
> > Signed-off-by: Michael S. Tsirkin <address@hidden>
> > ---
> > 
> > Sander, could you pleas econfirm this works for you?
> > Also, Xen really should switch to fw cfg some day ...
> 
> Yeah, especially because nowadays "-M pc" works with Xen.  It would be nice if
> fw_cfg could be enabled even for Xen on all machines except the legacy "-M
> xenfv".
> 
> Stefano, could you give it a shot now that you'll be soon done with 4.4?

It might not be that straightforward as Xen emulates some devices in the
hypervisor and patches have been recently posted to support multiple
device models for a single VM.

 
> >  hw/i386/pc_piix.c | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> > 
> > diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
> > index a327d71..1acd2b2 100644
> > --- a/hw/i386/pc_piix.c
> > +++ b/hw/i386/pc_piix.c
> > @@ -793,6 +793,17 @@ static QEMUMachine xenfv_machine = {
> >      .max_cpus = HVM_MAX_VCPUS,
> >      .default_machine_opts = "accel=xen",
> >      .hot_add_cpu = pc_hot_add_cpu,
> > +    .compat_props = (GlobalProperty[]) {
> > +        /* xenfv has no fwcfg and so does not load acpi from QEMU.
> > +         * as such new acpi features don't work.
> > +         */
> > +        {
> > +            .driver   = "PIIX4_PM",
> > +            .property = "acpi-pci-hotplug-with-bridge-support",
> > +            .value    = "off",
> > +        },
> > +        { /* end of list */ }
> > +    },
> >  };
> >  #endif
> > 
> > 
>