From 67d045a0ef5b9c5f871c3a1d87325a8a42d2b9d5 Mon Sep 17 00:00:00 2001 From: Ani Sinha Date: Tue, 11 Jul 2023 12:33:01 +0530 Subject: hw/pci: add comment to explain checking for available function 0 in pci hotplug 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 Signed-off-by: Michael Tokarev --- 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 784c02a..b8d22e2 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -1183,9 +1183,14 @@ 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), -- cgit v1.1