diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index c4256220..53879965 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -86,6 +86,15 @@ inline static uint64_t rdmsr(uint32_t msr) {
 	return ((uint64_t)high << 32) | low;
 }
 
+/*
+ * invalidate (not flush!) lines in L1 that map to MPB lines
+ */
+inline static void cache_invalidate(void) {
+#ifdef CONFIG_ROCKCREEK
+	asm volatile (".byte 0x0f; .byte 0x0a;\n" ); // CL1FLUSHMB
+#endif
+}
+
 #define NOP1 	asm  volatile ("nop")
 #define NOP2    asm  volatile ("nop;nop")
 #define NOP4    asm  volatile ("nop;nop;nop;nop")