diff --git a/README.adoc b/README.adoc
index b054900..9b9cc57 100644
--- a/README.adoc
+++ b/README.adoc
@@ -1210,7 +1210,11 @@ You can make QEMU or gem5 <<gem5-vs-qemu-performance,run faster>> by passing ena
 ./run -K
 ....
 
-but it was broken in gem5 with pending patches: https://www.mail-archive.com/gem5-users@gem5.org/msg15046.html
+but it was broken in gem5 with pending patches: https://www.mail-archive.com/gem5-users@gem5.org/msg15046.html It fails immediately on:
+
+....
+panic: KVM: Failed to enter virtualized mode (hw reason: 0x80000021)
+....
 
 KVM uses the link:https://en.wikipedia.org/wiki/Kernel-based_Virtual_Machine[KVM Linux kernel feature] of the host to run most instructions natively.