diff --git a/drivers/scsi/ncr53c8xx.c b/drivers/scsi/ncr53c8xx.c
index ceab4f73caf1..c57c94c0ffd2 100644
--- a/drivers/scsi/ncr53c8xx.c
+++ b/drivers/scsi/ncr53c8xx.c
@@ -8222,7 +8222,7 @@ static void process_waiting_list(struct ncb *np, int sts)
 #ifdef DEBUG_WAITING_LIST
 	if (waiting_list) printk("%s: waiting_list=%lx processing sts=%d\n", ncr_name(np), (u_long) waiting_list, sts);
 #endif
-	while (wcmd = waiting_list) {
+	while ((wcmd = waiting_list) != NULL) {
 		waiting_list = (struct scsi_cmnd *) wcmd->next_wcmd;
 		wcmd->next_wcmd = NULL;
 		if (sts == DID_OK) {