On Mon, 27 Sep 2021, Ján Tomko wrote:
> On a Monday in 2021, Ani Sinha wrote:
> > This change introduces libvirt xml support to enable/disable hotplug on the
> > pci-root controller. It adds a 'target' subelement for the pci-root
> > controller
> > with a 'hotplug' property. This property can be used to enable or disable
> > hotplug for the pci-root controller. For example, in order to disable
> > hotplug
> > on the pci-root controller, one has to use set '<target hotplug='off'>' as
> > shown below:
> >
> > <controller type='pci' model='pci-root'>
> > <target hotplug='off'/>
> > </controller>
> >
> > '<target hotplug='on'>' option would enable hotplug for pci-root controller.
> > This is also the default value. This option is only available for pc machine
> > types and is applicable for qemu only/kvm accelerator onlt.This feature was
>
> s/onlt./only. /
Will fix in v6.
>
> > introduced from qemu version 5.2 with the following change in qemu
> > repository:
> >
> > 3d7e78aa7777f ("Introduce a new flag for i440fx to disable PCI hotplug on
> > the root bus")
> >
> > The above qemu commit describes some reasons why users might to disable
> > hotplug
> > on PCI root buses.
> >
> > Related unit tests to exercise the new conf option has also been added.
> >
> > Signed-off-by: Ani Sinha <ani@xxxxxxxxxxx>
> > ---
> > docs/formatdomain.rst | 12 ++++----
> > src/qemu/qemu_validate.c | 9 +++++-
> > .../pc-i440fx-acpi-root-hotplug-disable.xml | 30 +++++++++++++++++++
> > .../pc-i440fx-acpi-root-hotplug-enable.xml | 30 +++++++++++++++++++
> > .../pc-i440fx-acpi-root-hotplug-disable.xml | 1 +
> > .../pc-i440fx-acpi-root-hotplug-enable.xml | 1 +
> > tests/qemuxml2xmltest.c | 4 +++
> > 7 files changed, 81 insertions(+), 6 deletions(-)
> > create mode 100644
> > tests/qemuxml2argvdata/pc-i440fx-acpi-root-hotplug-disable.xml
> > create mode 100644
> > tests/qemuxml2argvdata/pc-i440fx-acpi-root-hotplug-enable.xml
> > create mode 120000
> > tests/qemuxml2xmloutdata/pc-i440fx-acpi-root-hotplug-disable.xml
> > create mode 120000
> > tests/qemuxml2xmloutdata/pc-i440fx-acpi-root-hotplug-enable.xml
> >
> > @@ -3879,6 +3879,14 @@ qemuValidateDomainDeviceDefControllerPCI(const
> > virDomainControllerDef *cont,
> > /* hotplug */
> > if (pciopts->hotplug != VIR_TRISTATE_SWITCH_ABSENT) {
> > switch ((virDomainControllerModelPCI) cont->model) {
> > + case VIR_DOMAIN_CONTROLLER_MODEL_PCI_ROOT:
> > + if (!virQEMUCapsGet(qemuCaps,
> > QEMU_CAPS_PIIX_ACPI_ROOT_PCI_HOTPLUG)) {
> > + virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
> > + _("setting the %s property on a pci-root
> > device is not supported by this QEMU binary"),
> > + "hotplug");
>
> No need to create a new translatable string, the one used by the case
> below can be reused:
>
> virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
> _("setting the hotplug property on a '%s'
> device is not supported by this QEMU binary"),
> "pci-root");
yes very good suggestion. Will fix in v6.
