MdeModulePkg: Enhance PCI capability looking up logic to avoid hang

[mirror_edk2.git] / MdeModulePkg / Bus / Pci / PciBusDxe / PciCommand.c

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
index 8a8b4b8faca8bc6a42106b3d1e4497a60249b5f6..0bc1fbfefffe7b778642f90700b0a5fdc44f60e2 100644 (file)
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
@@ -173,6 +173,14 @@ LocateCapabilityRegBlock (
       return EFI_SUCCESS;\r
     }\r
 \r
+    //\r
+    // Certain PCI device may incorrectly have capability pointing to itself,\r
+    // break to avoid dead loop.\r
+    //\r
+    if (CapabilityPtr == (UINT8) (CapabilityEntry >> 8)) {\r
+      break;\r
+    }\r
+\r
     CapabilityPtr = (UINT8) (CapabilityEntry >> 8);\r
   }\r
 \r