[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH v4] hw/pci: enforce use of slot only slot 0 when devices have an
From: |
Ani Sinha |
Subject: |
[PATCH v4] hw/pci: enforce use of slot only slot 0 when devices have an upstream PCIE port |
Date: |
Tue, 20 Jun 2023 12:48:05 +0530 |
When a device has an upstream PCIE port, we can only use slot 0. Non-zero slots
are invalid. This change ensures that we throw an error if the user
tries to hotplug a device with an upstream PCIE port to a non-zero slot.
CC: jusual@redhat.com
CC: imammedo@redhat.com
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2128929
Signed-off-by: Ani Sinha <anisinha@redhat.com>
---
hw/pci/pci.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
changelog:
v2: addressed issue with multifunction pcie root ports. Should allow
hotplug on functions other than function 0.
v3: improved commit message.
v4: improve commit message and code comments further. Some more
improvements might come in v5. No claims made here that this is
the final one :-)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index bf38905b7d..30ce6a78cb 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -64,6 +64,7 @@ bool pci_available = true;
static char *pcibus_get_dev_path(DeviceState *dev);
static char *pcibus_get_fw_dev_path(DeviceState *dev);
static void pcibus_reset(BusState *qbus);
+static bool pcie_has_upstream_port(PCIDevice *dev);
static Property pci_props[] = {
DEFINE_PROP_PCI_DEVFN("addr", PCIDevice, devfn, -1),
@@ -1182,6 +1183,11 @@ static PCIDevice *do_pci_register_device(PCIDevice
*pci_dev,
} else if (dev->hotplugged &&
!pci_is_vf(pci_dev) &&
pci_get_function_0(pci_dev)) {
+ /*
+ * populating function 0 triggers a bus scan from the guest that
+ * exposes other non-zero functions. Hence we need to ensure that
+ * function 0 wasn't added yet.
+ */
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),
@@ -1189,6 +1195,18 @@ static PCIDevice *do_pci_register_device(PCIDevice
*pci_dev,
name);
return NULL;
+ } else if (dev->hotplugged &&
+ !pci_is_vf(pci_dev) &&
+ pcie_has_upstream_port(pci_dev) && PCI_SLOT(devfn)) {
+ /*
+ * If the device has an upstream PCIE port, like a pcie root port,
+ * we only support functions on slot 0.
+ */
+ error_setg(errp, "PCI: slot %d is not valid for %s,"
+ " only functions on slot 0 is supported for devices"
+ " with an upstream PCIE port.",
+ PCI_SLOT(devfn), name);
+ return NULL;
}
pci_dev->devfn = devfn;
--
2.39.1
- [PATCH v4] hw/pci: enforce use of slot only slot 0 when devices have an upstream PCIE port,
Ani Sinha <=
Re: [PATCH v4] hw/pci: enforce use of slot only slot 0 when devices have an upstream PCIE port, Michael S. Tsirkin, 2023/06/20