diff --git a/nixos/doc/manual/configuration/profiles/hardened.xml b/nixos/doc/manual/configuration/profiles/hardened.xml
index dc83fc837e2..4a51754cc7a 100644
--- a/nixos/doc/manual/configuration/profiles/hardened.xml
+++ b/nixos/doc/manual/configuration/profiles/hardened.xml
@@ -7,7 +7,7 @@
 
  <para>
   A profile with most (vanilla) hardening options enabled by default,
-  potentially at the cost of features and performance.
+  potentially at the cost of stability, features and performance.
  </para>
 
  <para>
@@ -21,4 +21,12 @@
    xlink:href="https://github.com/nixos/nixpkgs/tree/master/nixos/modules/profiles/hardened.nix">
   profile source</literal> for further detail on which settings are altered.
  </para>
+ <warning>
+   <para>
+     This profile enables options that are known to affect system
+     stability. If you experience any stability issues when using the
+     profile, try disabling it. If you report an issue and use this
+     profile, always mention that you do.
+   </para>
+ </warning>
 </section>
diff --git a/nixos/modules/profiles/hardened.nix b/nixos/modules/profiles/hardened.nix
index 42ed62b0630..680fa40b911 100644
--- a/nixos/modules/profiles/hardened.nix
+++ b/nixos/modules/profiles/hardened.nix
@@ -1,5 +1,10 @@
 # A profile with most (vanilla) hardening options enabled by default,
-# potentially at the cost of features and performance.
+# potentially at the cost of stability, features and performance.
+#
+# This profile enables options that are known to affect system
+# stability. If you experience any stability issues when using the
+# profile, try disabling it. If you report an issue and use this
+# profile, always mention that you do.
 
 { config, lib, pkgs, ... }: