diff --git a/README.adoc b/README.adoc
index 7b5f79e..65f688d 100644
--- a/README.adoc
+++ b/README.adoc
@@ -7310,6 +7310,14 @@ To get a terminal, either open a new shell and run:
 
 or use `./run -u` if you are using tmux, which I highly recommend: <<tmux-gem5>>.
 
+TODO: `arm` broken on kernel 4.18 with:
+
+....
+Internal error: Oops - undefined instruction
+....
+
+Workaround by checking out kernel 4.17 as explained at <<linux-kernel-build-variants>>.
+
 === gem5 vs QEMU
 
 * advantages of gem5: