diff --git a/arch/s390/pci/pci_debug.c b/arch/s390/pci/pci_debug.c
index 6b48ca7760a7..45eccf79e990 100644
--- a/arch/s390/pci/pci_debug.c
+++ b/arch/s390/pci/pci_debug.c
@@ -74,8 +74,8 @@ static void pci_sw_counter_show(struct seq_file *m)
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(pci_sw_names); i++, counter++)
-		seq_printf(m, "%26s:\t%lu\n", pci_sw_names[i],
-			   atomic64_read(counter));
+		seq_printf(m, "%26s:\t%llu\n", pci_sw_names[i],
+			   (s64)atomic64_read(counter));
 }
 
 static int pci_perf_show(struct seq_file *m, void *v)