diff --git a/drivers/misc/sgi-gru/grutables.h b/drivers/misc/sgi-gru/grutables.h
index 4251018..a78f70d 100644
--- a/drivers/misc/sgi-gru/grutables.h
+++ b/drivers/misc/sgi-gru/grutables.h
@@ -279,7 +279,7 @@
 #if defined CONFIG_IA64
 #define VADDR_HI_BIT		64
 #define GRUREGION(addr)		((addr) >> (VADDR_HI_BIT - 3) & 3)
-#elif defined __x86_64
+#elif defined CONFIG_X86_64
 #define VADDR_HI_BIT		48
 #define GRUREGION(addr)		(0)		/* ZZZ could do better */
 #else