| Message ID | 20230711070301.4353-1-anisinha@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | [RESEND] hw/pci: add comment to explain checking for available function 0 in pci hotplug | expand |
> On 11-Jul-2023, at 12:33 PM, 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 > CC: mjt@tls.msk.ru > Signed-off-by: Ani Sinha <anisinha@redhat.com> Can we merge this while we are still in rc0? > --- > hw/pci/pci.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/hw/pci/pci.c b/hw/pci/pci.c > index e2eb4c3b4a..6db18dfe46 100644 > --- a/hw/pci/pci.c > +++ b/hw/pci/pci.c > @@ -1180,9 +1180,14 @@ 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. > + */ > + 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), > -- > 2.39.1 >
diff --git a/hw/pci/pci.c b/hw/pci/pci.c index e2eb4c3b4a..6db18dfe46 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -1180,9 +1180,14 @@ 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. + */ + 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 CC: mjt@tls.msk.ru Signed-off-by: Ani Sinha <anisinha@redhat.com> --- hw/pci/pci.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)