[BOLT] Fix stuck for x86 linux kernel 5.10

The paravirtualization of kernel will update function implementation
at runtime.
For funtions involving paravirtualization, mark them as non-optimizable
at appropriate locations.

Author: Jianghibo

bolt/lib/Rewrite/LinuxKernelRewriter.cpp

@@ -337,6 +337,7 @@ class LinuxKernelRewriter final : public MetadataRewriter {
   /// Paravirtual instruction patch sites.
   Error readParaInstructions();
   Error rewriteParaInstructions();
+  void processParaInstructionsPostCFG();
 
   /// __bug_table section handling.
   Error readBugTable();
@@ -445,6 +446,7 @@ class LinuxKernelRewriter final : public MetadataRewriter {
     if (Error E = processORCPostCFG())
       return E;
 
+    processParaInstructionsPostCFG();
     processAltInstructionsPostCFG();
 
     return Error::success();
@@ -1435,10 +1437,6 @@ Error LinuxKernelRewriter::readParaInstructions() {
     }
   }
 
-  // Disable output of functions with paravirtual instructions before the
-  // rewrite support is complete.
-  skipFunctionsWithAnnotation("ParaSite");
-
   BC.outs() << "BOLT-INFO: parsed " << EntryID << " paravirtual patch sites\n";
 
   return Error::success();
@@ -1461,6 +1459,12 @@ void LinuxKernelRewriter::skipFunctionsWithAnnotation(
   }
 }
 
+void LinuxKernelRewriter::processParaInstructionsPostCFG() {
+  // Disable output of functions with paravirtual instructions before the
+  // rewrite support is complete.
+  skipFunctionsWithAnnotation("ParaSite");
+}
+
 Error LinuxKernelRewriter::rewriteParaInstructions() {
   return Error::success();
 }