diff --git a/README.adoc b/README.adoc
index 9ecf844..7dd9751 100644
--- a/README.adoc
+++ b/README.adoc
@@ -2436,6 +2436,10 @@ Bibliography:
 
 === arm
 
+QEMU 3.0.0-rc3 and 3.0.0-rc4 boot failing: http://lists.nongnu.org/archive/html/qemu-discuss/2018-08/msg00030.html
+
+Workaround for now by going back to v2.12.0 with <<qemu-build-variants>>.
+
 ==== Run arm executable in aarch64
 
 TODO Can you run arm executables in the aarch64 guest? https://stackoverflow.com/questions/22460589/armv8-running-legacy-32-bit-applications-on-64-bit-os/51466709#51466709
@@ -8635,6 +8639,19 @@ The `-L` option should be passed to all scripts that support it, much like `-a`
 
 This technique is implemented semi-hackishly by moving symlinks around inside the Buildroot build dir at build time, and selecting the right build directory at runtime.
 
+==== QEMU build variants
+
+Analogous to the <<linux-kernel-build-variants>> but with the `-Q` option instead:
+
+....
+./build
+git -C qemu checkout v2.12.0
+./build -Q v2.12.0 -q
+git -C linux checkout -
+./run
+./run -Q v2.12.0
+....
+
 ==== gem5 build variants
 
 Analogous to the <<linux-kernel-build-variants>> but with the `-M` option instead: