Why do you need this tool ??
https://git.kernel.org/pub/scm/utils/kernel/kexec/kexec-tools.git
I had wanted to compile it a couple of weeks ago, but then I read
here that one must be able (among other things) to unload graphics driver
"The graphics driver needs to be unloaded before a kexec, or the next kernel will not be able to gain exclusive control of the device. This is difficult to achieve manually because any programs which need exclusive control over the GPU (Xorg, display managers) must not be running."
I had hoped I could reboot the ramdrive 'as is', so to not have to redownload all packages and more interestinglly, not have to figure out some way to store and retrieve some files, as they should just still be there using kexec.. Additionally this might have allowed to get rid of loaded extensions (which is a nightmare to attempt otherwise
).