diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 292fcb174a32..fab33a9c5318 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -38,6 +38,8 @@
  * @cp: The start of the string
  * @endp: A pointer to the end of the parsed string will be placed here
  * @base: The number base to use
+ *
+ * This function is obsolete. Please use kstrtoull instead.
  */
 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
 {
@@ -61,6 +63,8 @@ EXPORT_SYMBOL(simple_strtoull);
  * @cp: The start of the string
  * @endp: A pointer to the end of the parsed string will be placed here
  * @base: The number base to use
+ *
+ * This function is obsolete. Please use kstrtoul instead.
  */
 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
 {
@@ -73,6 +77,8 @@ EXPORT_SYMBOL(simple_strtoul);
  * @cp: The start of the string
  * @endp: A pointer to the end of the parsed string will be placed here
  * @base: The number base to use
+ *
+ * This function is obsolete. Please use kstrtol instead.
  */
 long simple_strtol(const char *cp, char **endp, unsigned int base)
 {
@@ -88,6 +94,8 @@ EXPORT_SYMBOL(simple_strtol);
  * @cp: The start of the string
  * @endp: A pointer to the end of the parsed string will be placed here
  * @base: The number base to use
+ *
+ * This function is obsolete. Please use kstrtoll instead.
  */
 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
 {