Separate DSC configuration parser check for ARM processor (#21395)

src/System.Management.Automation/engine/parser/Parser.cs

@@ -2984,8 +2984,8 @@ namespace System.Management.Automation.Language
                     Runspaces.Runspace.DefaultRunspace = localRunspace;
                 }
 
-                // Configuration is not supported on ARM or in ConstrainedLanguage
-                if (PsUtils.IsRunningOnProcessorArchitectureARM() || Runspace.DefaultRunspace?.ExecutionContext?.LanguageMode == PSLanguageMode.ConstrainedLanguage)
+                // Configuration is not supported in ConstrainedLanguage
+                if (Runspace.DefaultRunspace?.ExecutionContext?.LanguageMode == PSLanguageMode.ConstrainedLanguage)
                 {
                     if (SystemPolicy.GetSystemLockdownPolicy() != SystemEnforcementMode.Audit)
                     {
@@ -3004,6 +3004,17 @@ namespace System.Management.Automation.Language
                         dropIntoDebugger: true);
                 }
 
+                // Configuration is not supported on ARM64
+                if (PsUtils.IsRunningOnProcessorArchitectureARM())
+                {
+                    ReportError(
+                        configurationToken.Extent,
+                        nameof(ParserStrings.ConfigurationNotAllowedOnArm64),
+                        ParserStrings.ConfigurationNotAllowedOnArm64,
+                        configurationToken.Kind.Text());
+                    return null;
+                }
+
                 // Configuration is not supported on WinPE
                 if (Utils.IsWinPEHost())
                 {

src/System.Management.Automation/resources/ParserStrings.resx

@@ -1370,4 +1370,7 @@ ModuleVersion : Version of module to import. If used, ModuleName must represent
   <data name="WDACGetSteppablePipelineLogMessage" xml:space="preserve">
     <value>Creating a steppable pipeline from a script block may require evaluating some expressions within the script block. The expression evaluation will silently fail and return 'null' in Constrained Language mode, unless the expression represents a constant value.</value>
   </data>
+  <data name="ConfigurationNotAllowedOnArm64" xml:space="preserve">
+    <value>Configuration keyword is not supported on ARM64 processors.</value>
+  </data>
 </root>