diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 2d83b8c7596567a020300d8dd1aeefeb33a6a055..e157a0e4441916b77b53c402741b74e124012cc9 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -6800,7 +6800,7 @@ static int __init ata_parse_force_one(char **cur,
 	}
 
 	force_ent->port = simple_strtoul(id, &endp, 10);
-	if (p == endp || *endp != '\0') {
+	if (id == endp || *endp != '\0') {
 		*reason = "invalid port/link";
 		return -EINVAL;
 	}