OcAppleBootCompatLib: Add comments about MAT issues

Library/OcAppleBootCompatLib/ServiceOverrides.c

@@ -55,6 +55,13 @@ FixRuntimeAttributes (
   }
 
   if (BootCompat->Settings.SyncRuntimePermissions && BootCompat->ServiceState.FwRuntime != NULL) {
+    //
+    // Some firmwares do not update MAT after loading runtime drivers after EndOfDxe.
+    // Since the memory used to allocate runtime driver resides in BINs, MAT has whatever
+    // permissions designated for unused memory. Mark unused memory containing our driver
+    // as executable here.
+    // REF: https://github.com/acidanthera/bugtracker/issues/491#issuecomment-606835337
+    //
     Status = BootCompat->ServiceState.FwRuntime->GetExecArea (&Address, &Pages);
 
     if (!EFI_ERROR (Status)) {
@@ -438,6 +445,10 @@ OcGetMemoryMap (
   }
 
   if (BootCompat->Settings.SyncRuntimePermissions && BootCompat->ServiceState.FwRuntime != NULL) {
+    //
+    // Some firmwares mark runtime drivers loaded after EndOfDxe as EfiRuntimeServicesData:
+    // REF: https://github.com/acidanthera/bugtracker/issues/791#issuecomment-607935508
+    //
     Status2 = BootCompat->ServiceState.FwRuntime->GetExecArea (&Address, &Pages);
 
     if (!EFI_ERROR (Status2)) {