| Message ID | 20230704112555.5629-7-anisinha@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | test and QEMU fixes to ensure proper PCIE device usage | expand |
On Tue, 4 Jul 2023 16:55:55 +0530 Ani Sinha <anisinha@redhat.com> wrote: > This change is cosmetic. A comment is added explaining why we need to check for > the availability of function 0 when we hotplug a device. > > CC: mst@redhat.com > Signed-off-by: Ani Sinha <anisinha@redhat.com> > --- > hw/pci/pci.c | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git a/hw/pci/pci.c b/hw/pci/pci.c > index 47517ba3db..e3ff3808b6 100644 > --- a/hw/pci/pci.c > +++ b/hw/pci/pci.c > @@ -1181,9 +1181,15 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, > PCI_SLOT(devfn), PCI_FUNC(devfn), name, > bus->devices[devfn]->name, bus->devices[devfn]->qdev.id); > return NULL; > - } else if (dev->hotplugged && > - !pci_is_vf(pci_dev) && > - pci_get_function_0(pci_dev)) { > + } /* > + * Populating function 0 triggers a scan from the guest that > + * exposes other non-zero functions. Hence we need to ensure that > + * function 0 wasn't added yet. > With SRIOV and with or without ARI > + * the PF must be hotplugged into function 0 for it to be detected. Wouldn't the same apply to non-SR-IOV devices as well? > + */ > + else if (dev->hotplugged && > + !pci_is_vf(pci_dev) && > + pci_get_function_0(pci_dev)) { > error_setg(errp, "PCI: slot %d function 0 already occupied by %s," > " new func %s cannot be exposed to guest.", > PCI_SLOT(pci_get_function_0(pci_dev)->devfn),
On Tue, 4 Jul, 2023, 5:45 pm Igor Mammedov, <imammedo@redhat.com> wrote: > On Tue, 4 Jul 2023 16:55:55 +0530 > Ani Sinha <anisinha@redhat.com> wrote: > > > This change is cosmetic. A comment is added explaining why we need to > check for > > the availability of function 0 when we hotplug a device. > > > > CC: mst@redhat.com > > Signed-off-by: Ani Sinha <anisinha@redhat.com> > > --- > > hw/pci/pci.c | 12 +++++++++--- > > 1 file changed, 9 insertions(+), 3 deletions(-) > > > > diff --git a/hw/pci/pci.c b/hw/pci/pci.c > > index 47517ba3db..e3ff3808b6 100644 > > --- a/hw/pci/pci.c > > +++ b/hw/pci/pci.c > > @@ -1181,9 +1181,15 @@ static PCIDevice > *do_pci_register_device(PCIDevice *pci_dev, > > PCI_SLOT(devfn), PCI_FUNC(devfn), name, > > bus->devices[devfn]->name, bus->devices[devfn]-> > qdev.id); > > return NULL; > > - } else if (dev->hotplugged && > > - !pci_is_vf(pci_dev) && > > - pci_get_function_0(pci_dev)) { > > + } /* > > + * Populating function 0 triggers a scan from the guest that > > + * exposes other non-zero functions. Hence we need to ensure that > > + * function 0 wasn't added yet. > > > With SRIOV and with or without ARI > > + * the PF must be hotplugged into function 0 for it to be > detected. > Wouldn't the same apply to non-SR-IOV devices as well? > I was trying to emphasize PFs and SRIOV. But may be it adds more confusion and better left out. > > > + */ > > + else if (dev->hotplugged && > > + !pci_is_vf(pci_dev) && > > + pci_get_function_0(pci_dev)) { > > error_setg(errp, "PCI: slot %d function 0 already occupied by > %s," > > " new func %s cannot be exposed to guest.", > > PCI_SLOT(pci_get_function_0(pci_dev)->devfn), > >
diff --git a/hw/pci/pci.c b/hw/pci/pci.c index 47517ba3db..e3ff3808b6 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -1181,9 +1181,15 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, PCI_SLOT(devfn), PCI_FUNC(devfn), name, bus->devices[devfn]->name, bus->devices[devfn]->qdev.id); return NULL; - } else if (dev->hotplugged && - !pci_is_vf(pci_dev) && - pci_get_function_0(pci_dev)) { + } /* + * Populating function 0 triggers a scan from the guest that + * exposes other non-zero functions. Hence we need to ensure that + * function 0 wasn't added yet. With SRIOV and with or without ARI + * the PF must be hotplugged into function 0 for it to be detected. + */ + else if (dev->hotplugged && + !pci_is_vf(pci_dev) && + pci_get_function_0(pci_dev)) { error_setg(errp, "PCI: slot %d function 0 already occupied by %s," " new func %s cannot be exposed to guest.", PCI_SLOT(pci_get_function_0(pci_dev)->devfn),
This change is cosmetic. A comment is added explaining why we need to check for the availability of function 0 when we hotplug a device. CC: mst@redhat.com Signed-off-by: Ani Sinha <anisinha@redhat.com> --- hw/pci/pci.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)