Merge "Warn about certificate serial number size" into main
diff --git a/keystore/java/android/security/keystore/KeyGenParameterSpec.java b/keystore/java/android/security/keystore/KeyGenParameterSpec.java
index d359a90..3cff915 100644
--- a/keystore/java/android/security/keystore/KeyGenParameterSpec.java
+++ b/keystore/java/android/security/keystore/KeyGenParameterSpec.java
@@ -1149,6 +1149,8 @@
/**
* Sets the serial number used for the certificate of the generated key pair.
+ * To ensure compatibility with devices and certificate parsers, the value
+ * should be 20 bytes or shorter (see RFC 5280 section 4.1.2.2).
*
* <p>By default, the serial number is {@code 1}.
*/