diff --git a/reactos/include/ntos/halfuncs.h b/reactos/include/ntos/halfuncs.h
index eee1b43f22c..c2541aa6c06 100755
--- a/reactos/include/ntos/halfuncs.h
+++ b/reactos/include/ntos/halfuncs.h
@@ -49,6 +49,9 @@ KeRaiseIrqlToSynchLevel(VOID);
 VOID STDCALL
 HalReturnToFirmware(ULONG Action);
 
+VOID FASTCALL
+HalRequestSoftwareInterrupt(KIRQL SoftwareInterruptRequested);
+
 /* Non-standard functions */
 VOID STDCALL
 HalReleaseDisplayOwnership();