RFC: handling kernel cmdline options in gadget snaps

[Sergio Schvezov]

On Tue, Jul 07, 2015 at 11:37:12AM -0600, Ben Howard wrote:
> 
> What about making /etc/default/grub.d a writable path? Then a user would
> simply need to provide a config with
> GRUB_CMDLINE_LINUX_DEFAULT="console=tty1".
> 
> But I think that this highlights the need for providing a simple way for
> users to populate the writable paths at build time. As I have been
> building Cloud Images, its a PITA to populate the writable paths. I
> think that having a "--writable <tarball>" option that takes <tarball>
> and populates /writable with the contents could solve a lot of pain.
> Having this feature would mean that instead of having to support the
> never-ending whack-a-mole requirements of "--<whatever>", users could
> use "--writable <tarball>".

I;m lobbying for doing most of this through snappy config. A big blob of
config to setup and I don't mind having a syntax that looks like:

    ubuntu-device-flash core 15.04 --config config.yaml ...

For what it's worth, those grub dirs have become irrelevant and snappy
has complete control of the bootloader in the development series. You
can easily write your own grub.cfg from the gadget today.