diff --git a/lib/test_printf.c b/lib/test_printf.c
index 5d94cbf..d4b711b 100644
--- a/lib/test_printf.c
+++ b/lib/test_printf.c
@@ -212,6 +212,7 @@
 #define PTR_STR "ffff0123456789ab"
 #define PTR_VAL_NO_CRNG "(____ptrval____)"
 #define ZEROS "00000000"	/* hex 32 zero bits */
+#define ONES "ffffffff"		/* hex 32 one bits */
 
 static int __init
 plain_format(void)
@@ -243,6 +244,7 @@
 #define PTR_STR "456789ab"
 #define PTR_VAL_NO_CRNG "(ptrval)"
 #define ZEROS ""
+#define ONES ""
 
 static int __init
 plain_format(void)
@@ -328,14 +330,28 @@
 	test(buf, fmt, p);
 }
 
+/*
+ * NULL pointers aren't hashed.
+ */
 static void __init
 null_pointer(void)
 {
-	test_hashed("%p", NULL);
+	test(ZEROS "00000000", "%p", NULL);
 	test(ZEROS "00000000", "%px", NULL);
 	test("(null)", "%pE", NULL);
 }
 
+/*
+ * Error pointers aren't hashed.
+ */
+static void __init
+error_pointer(void)
+{
+	test(ONES "fffffff5", "%p", ERR_PTR(-11));
+	test(ONES "fffffff5", "%px", ERR_PTR(-11));
+	test("(efault)", "%pE", ERR_PTR(-11));
+}
+
 #define PTR_INVALID ((void *)0x000000ab)
 
 static void __init
@@ -598,6 +614,7 @@
 {
 	plain();
 	null_pointer();
+	error_pointer();
 	invalid_pointer();
 	symbol_ptr();
 	kernel_ptr();