Re: [Qemu-devel] [PATCH] pc: piix4_pm: init legacy PCI hotplug when running on Xen

[Stefano Stabellini]

On Tue, 4 Nov 2014, Paolo Bonzini wrote:
> On 04/11/2014 11:36, Stefano Stabellini wrote:
> > Feng, thanks for the email.
> > 
> > I was assuming that one of the other maintainers would take care of the
> > patch, but I am happy to submit a pull request for it too.
> > 
> > Paolo, Michael?
> 
> I think this patch is not okay, because Xen does use fw_cfg when you
> have -kernel.  So I think you should really use "if (xen_enabled())".
 
Well spotted! The original patch was submitted before we introduced
-kernel to hvm guests.

If (xen_enabled()) would work.



> >>> diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
> >>> index 227ea30..12542c3 100644
> >>> --- a/hw/acpi/piix4.c
> >>> +++ b/hw/acpi/piix4.c
> >>> @@ -501,6 +501,9 @@ I2CBus *piix4_pm_init(PCIBus *bus, int devfn,
> >>> uint32_t smb_io_base,
> >>>      s->irq = sci_irq;
> >>>      s->smi_irq = smi_irq;
> >>>      s->kvm_enabled = kvm_enabled;
> >>> +    if (!fw_cfg) {
> >>> +        s->use_acpi_pci_hotplug = false;
> >>> +    }
> >>>
> >>>      qdev_init_nofail(dev);
> >>>
> >>> diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
> >>> index a13e8d6..067ff0c 100644
> >>> --- a/hw/i386/pc_piix.c
> >>> +++ b/hw/i386/pc_piix.c
> >>> @@ -840,17 +840,6 @@ 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
> >>>
> >>> --
> >>> 1.9.0
> >>>
> >>
>