diff --git a/sys/compat/linux/linux.h b/sys/compat/linux/linux.h
index 5a0d6e0b68c..6d276b8a69f 100644
--- a/sys/compat/linux/linux.h
+++ b/sys/compat/linux/linux.h
@@ -350,7 +350,9 @@ struct l_statx {
 #define	LINUX_ST_RELATIME		0x1000	/* No native analogue */
 #define	LINUX_ST_NOSYMFOLLOW		0x2000
 
+#ifndef lower_32_bits
 #define	lower_32_bits(n)	((uint32_t)((n) & 0xffffffff))
+#endif
 
 #ifdef KTRACE
 #define	linux_ktrsigset(s, l)	\