Linux build system can install modules into an alternate directory through INSTALL_MOD_PATH environment variable. However, current mkinitrd will always search for modules in /lib/modules. It would be nice to have the tool to search the modules from the freshly installed alternate location. I'm attaching a proposed patch for this.
Created attachment 162026 [details] proposed patch
mkinitrd now uses modprobe, from module-init-tools to accomplish this task. If this functionality is still desired, it'd need to be added there.