Wei, No you cannot install gEfiPciEnumerationCompleteProtocolGuid in PciEnumeratorLight(). For a real platform, PCI BUS is fully enumerated in PciEnumerator() and later if reconnect happens, it's light enumerated in PciEnumeratorLight(). The protocol should only be installed once in PeiEnumerator(). Your fix will cause this protocol installed every time a reconnect happens. The protocol 's meaning is that the PCI BUS is fully enumerated. If the PCI BUS is fully enumerated before starting PciBus driver, light PCI enumeration is used. For your OVMF/QEMU case, an alternative fix is to install this protocol in a platform driver when it detects that the PCI BUS is fully enumerated.
Thanks, Ray -----Original Message----- From: Wei Liu [mailto:wei.l...@citrix.com] Sent: Thursday, February 12, 2015 4:24 AM To: edk2-de...@lists.sourceforge.net Cc: xen-devel@lists.xen.org; Laszlo Subject: [edk2] [PATCH] MdeModulePkg: mark completion of PCI enumeration in PciEnumeratorLight I had an issue when trying to boot Xen HVM guest with latest OVMF master. Guest crashed with memory violation, and the bisection pointed to 66b280df2 ("OvmfPkg: AcpiPlatformDxe: make dependency on PCI enumeration explicit"). That commit made AcpiPlatformDxe depend on PCI enumeration using gEfiPciEnumerationCompleteProtocolGuid, which is a very reasonable change. The real culprit is that Xen HVM is using PciEnumeratorLight which doesn't install gEfiPciEnumerationCompleteProtocolGuid. This, in combination with 66b280df2, makes AcpiPlatformDxe not able to be loaded, resulting in guest crash. The fix is to install gEfiPciEnumerationCompleteProtocolGuid in PciEnumeratorLight. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Wei Liu <wei.l...@citrix.com> Cc: Feng Tian <feng.t...@intel.com> Cc: Anthony Perard <anthony.per...@citrix.com> Cc: Laszlo Ersek <ler...@redhat.com> Cc: Jordan Justen <jordan.l.jus...@intel.com> --- MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c index 9e7ac74..7659585 100644 --- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c +++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c @@ -2256,6 +2256,7 @@ PciEnumeratorLight ( { EFI_STATUS Status; + EFI_HANDLE HostBridgeHandle; EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL *PciRootBridgeIo; PCI_IO_DEVICE *RootBridgeDev; UINT16 MinBus; @@ -2288,6 +2289,11 @@ PciEnumeratorLight ( return Status; } + // + // Get the host bridge handle + // + HostBridgeHandle = PciRootBridgeIo->ParentHandle; + Status = PciRootBridgeIo->Configuration (PciRootBridgeIo, (VOID **) &Descriptors); if (EFI_ERROR (Status)) { @@ -2348,7 +2354,14 @@ PciEnumeratorLight ( Descriptors++; } - return EFI_SUCCESS; + Status = gBS->InstallProtocolInterface ( + &HostBridgeHandle, + &gEfiPciEnumerationCompleteProtocolGuid, + EFI_NATIVE_INTERFACE, + NULL + ); + + return Status; } /** -- 1.9.1 ------------------------------------------------------------------------------ Dive into the World of Parallel Programming. The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ edk2-devel mailing list edk2-de...@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/edk2-devel _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
