diff --git a/etc/default/grub.d/40_cpu_mitigations.cfg b/etc/default/grub.d/40_cpu_mitigations.cfg
index b683200..ee6a2df 100644
--- a/etc/default/grub.d/40_cpu_mitigations.cfg
+++ b/etc/default/grub.d/40_cpu_mitigations.cfg
@@ -70,6 +70,7 @@ GRUB_CMDLINE_LINUX="$GRUB_CMDLINE_LINUX mmio_stale_data=full,nosmt"
 ## Enable mitigations for RETBleed (Arbitrary Speculative Code Execution with
 ## Return Instructions) vulnerability and disable SMT.
 ##
+## https://www.suse.com/support/kb/doc/?id=000020693
 GRUB_CMDLINE_LINUX="$GRUB_CMDLINE_LINUX retbleed=auto,nosmt"
 
 ## Control RAS overflow mitigation on AMD Zen CPUs.