diff --git a/sdk/cmake/config.cmake b/sdk/cmake/config.cmake
index 77b26a0383e..fb737211f02 100644
--- a/sdk/cmake/config.cmake
+++ b/sdk/cmake/config.cmake
@@ -92,8 +92,6 @@ else()
     set(_WINKD_ FALSE CACHE BOOL "Whether to compile with the KD protocol.")
 endif()
 
-option(BUILD_MP "Whether to build the multiprocessor versions of NTOSKRNL and HAL." ON)
-
 cmake_dependent_option(ISAPNP_ENABLE "Whether to enable the ISA PnP support." ON
                        "ARCH STREQUAL i386 AND NOT SARCH STREQUAL xbox" OFF)