ping. > -----Original Message----- > From: Yao Xingtao <yaoxt.f...@fujitsu.com> > Sent: Thursday, July 25, 2024 5:38 PM > To: m...@redhat.com; marcel.apfelb...@gmail.com > Cc: qemu-devel@nongnu.org; Yao, Xingtao/姚 幸涛 <yaoxt.f...@fujitsu.com> > Subject: [PATCH v4] pci-bridge: avoid linking a single downstream port more > than > once > > Since the downstream port is not checked, two slots can be linked to > a single port. However, this can prevent the driver from detecting the > device properly. > > It is necessary to ensure that a downstream port is not linked more than > once. > > Links: > https://lore.kernel.org/qemu-devel/OSZPR01MB6453BC61D2FF4035F18084EF8D > d...@oszpr01mb6453.jpnprd01.prod.outlook.com > Signed-off-by: Yao Xingtao <yaoxt.f...@fujitsu.com> > > --- > V3[3] -> V4: > - make the error message more readable > - fix the downstream port check error > > V2[2] -> V3: > - Move this check into pcie_cap_init() > > V1[1] -> V2: > - Move downstream port check forward > > [1] > https://lore.kernel.org/qemu-devel/20240704033834.3362-1-yaoxt.f...@fujitsu.co > m > [2] > https://lore.kernel.org/qemu-devel/20240717085621.55315-1-yaoxt.fnst@fujitsu.c > om > [3] > https://lore.kernel.org/qemu-devel/20240725032731.13032-1-yaoxt.fnst@fujitsu.c > om > --- > hw/pci/pcie.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c > index 4b2f0805c6e0..1e53be1bc7c5 100644 > --- a/hw/pci/pcie.c > +++ b/hw/pci/pcie.c > @@ -192,6 +192,13 @@ int pcie_cap_init(PCIDevice *dev, uint8_t offset, > > assert(pci_is_express(dev)); > > + if ((type == PCI_EXP_TYPE_DOWNSTREAM || type == > PCI_EXP_TYPE_ROOT_PORT) && > + pcie_find_port_by_pn(pci_get_bus(dev), port)) { > + error_setg(errp, "The port %d is already in use, please select " > + "another port", port); > + return -EBUSY; > + } > + > pos = pci_add_capability(dev, PCI_CAP_ID_EXP, offset, > PCI_EXP_VER2_SIZEOF, errp); > if (pos < 0) { > -- > 2.41.0
