diff --git a/include/linux/lzo.h b/include/linux/lzo.h
index 582d8b7..d793497 100644
--- a/include/linux/lzo.h
+++ b/include/linux/lzo.h
@@ -17,7 +17,7 @@
 #define LZO1X_MEM_COMPRESS	(16384 * sizeof(unsigned char *))
 #define LZO1X_1_MEM_COMPRESS	LZO1X_MEM_COMPRESS
 
-#define lzo1x_worst_compress(x) (x + (x / 64) + 16 + 3)
+#define lzo1x_worst_compress(x) ((x) + ((x) / 16) + 64 + 3)
 
 /* This requires 'workmem' of size LZO1X_1_MEM_COMPRESS */
 int lzo1x_1_compress(const unsigned char *src, size_t src_len,