downgrade linux kernel: you may need to change this repo to match buildroot

#39

Author: cirosantilli

README.adoc

@@ -4115,6 +4115,19 @@ Those commits change `BR2_LINUX_KERNEL_LATEST_VERSION` in `/linux/Config.in`.
 
 You should then look up if there is a branch that supports that kernel. Staying on branches is a good idea as they will get backports, in particular ones that fix the build as newer host versions come out.
 
+Finally, after downgrading Buildroot, if something does not work, you might also have to make some changes to how this repo uses Buildroot, as the Buildroot configuration options might have changed.
+
+We don't expect those changes to be very difficult. A good way to approach the task is to:
+
+* do a dry run build to get the equivalent Bash commands used:
++
+....
+./build-buildroot --dry-run
+....
+* build the Buildroot documentation for the version you are going to use, and check if all Buildroot build commands make sense there
+
+Then, if you spot an option that is wrong, some grepping in this repo should quickly point you to the code you need to modify.
+
 === Kernel command line parameters
 
 Bootloaders can pass a string as input to the Linux kernel when it is booting to control its behaviour, much like the `execve` system call does to userland processes.