diff --git a/sys/isa/isa_common.c b/sys/isa/isa_common.c
--- a/sys/isa/isa_common.c
+++ b/sys/isa/isa_common.c
@@ -275,12 +275,7 @@
 static int
 find_next_bit(uint32_t mask, int bit)
 {
-	bit++;
-	while (bit < 32 && !(mask & (1 << bit)))
-		bit++;
-	if (bit != 32)
-		return (bit);
-	return (-1);
+	return (find_first_bit(mask & (-2 << bit)));
 }
 
 /*