[PATCH V4 06/31] UefiCpuPkg/CpuExceptionHandler: Add base support for the #VE exception

["Min Xu" <min.m.xu@intel.com>]

RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3429

Add base support to handle #VE exceptions. Update the common exception
handlers to invoke the VmTdExitHandleVe () function of the VmgExitLib
library when a #VE is encountered. A non-zero return code will propagate
to the targeted exception handler.

Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>
---
 .../PeiDxeSmmCpuException.c                    | 17 +++++++++++++++++
 .../SecPeiCpuException.c                       | 18 ++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/PeiDxeSmmCpuException.c b/UefiCpuPkg/Library/CpuExceptionHandlerLib/PeiDxeSmmCpuException.c
index 762ea2460f91..4fa3f8202a33 100644
--- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/PeiDxeSmmCpuException.c
+++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/PeiDxeSmmCpuException.c
@@ -45,6 +45,23 @@ CommonExceptionHandlerWorker (
     }
   }
 
+  if (ExceptionType == VE_EXCEPTION) {
+    EFI_STATUS  Status;
+    //
+    // #VE needs to be handled immediately upon enabling exception handling
+    // and therefore can't use the RegisterCpuInterruptHandler() interface.
+    //
+    // Handle the #VE:
+    //   On EFI_SUCCESS - Exception has been handled, return
+    //   On other       - ExceptionType contains (possibly new) exception
+    //                    value
+    //
+    Status = VmTdExitHandleVe (&ExceptionType, SystemContext);
+    if (!EFI_ERROR (Status)) {
+      return;
+    }
+  }
+
   ExceptionHandlerContext  = (EXCEPTION_HANDLER_CONTEXT *)(UINTN)(SystemContext.SystemContextIa32);
   ReservedVectors          = ExceptionHandlerData->ReservedVectors;
   ExternalInterruptHandler = ExceptionHandlerData->ExternalInterruptHandler;
diff --git a/UefiCpuPkg/Library/CpuExceptionHandlerLib/SecPeiCpuException.c b/UefiCpuPkg/Library/CpuExceptionHandlerLib/SecPeiCpuException.c
index c614d5b0b6f1..148d89011721 100644
--- a/UefiCpuPkg/Library/CpuExceptionHandlerLib/SecPeiCpuException.c
+++ b/UefiCpuPkg/Library/CpuExceptionHandlerLib/SecPeiCpuException.c
@@ -43,6 +43,24 @@ CommonExceptionHandler (
     }
   }
 
+  if (ExceptionType == VE_EXCEPTION) {
+    EFI_STATUS  Status;
+    //
+    // #VE needs to be handled immediately upon enabling exception handling
+    // and therefore can't use the RegisterCpuInterruptHandler() interface
+    // (which isn't supported under Sec and Pei anyway).
+    //
+    // Handle the #VE:
+    //   On EFI_SUCCESS - Exception has been handled, return
+    //   On other       - ExceptionType contains (possibly new) exception
+    //                    value
+    //
+    Status = VmTdExitHandleVe (&ExceptionType, SystemContext);
+    if (!EFI_ERROR (Status)) {
+      return;
+    }
+  }
+
   //
   // Initialize the serial port before dumping.
   //
-- 
2.29.2.windows.2