Re: [PATCH] Add GRUB_DISABLE_UUID.

[Javier Martinez Canillas]

Hello Daniel,

On 9/18/19 2:39 PM, Daniel Kiper wrote:
> Adding Nicholas...
> 
> On Tue, Sep 17, 2019 at 05:48:45PM +0200, Javier Martinez Canillas wrote:
>> From: Peter Jones <address@hidden>
>>
>> This will cause "search --fs-uuid --set=root ..." not to be generated by
>> grub2-mkconfig, and instead simply attempt to use the grub device name
>> as it understands it.
>>
>> Signed-off-by: Peter Jones <address@hidden>
>> Signed-off-by: Javier Martinez Canillas <address@hidden>
> 
> We have this functionality in GRUB upstream. Please take a look at
> commit 51be3372e (templates: Update grub script template files).
> Could you pick it up in RH/Fedora?
>

That commit does something different if I'm reading it correctly. It's about
allowing to set the root kernel command line parameter to a PARTUUID instead
of a UUID or a device name, by using the grub-probe --target=partuuid option.

But Peter's patch is about setting the root param to a device name instead
of a UUID.

And also about not adding search commands in the grub.cfg to set the $root
and $boot grub environment variables by searching using a UUID.

Now digging more I found that there's already a GRUB_DISABLE_LINUX_UUID option
for the first part, so we only need to add an option for the second part.

Since this is not about Linux not using a UUID but grub not using it, I think
that we should add another option as this patch does. So GRUB_DISABLE_LINUX_UUID
would disable using a UUID for the root param and GRUB_DISABLE_UUID would be
about disabling using a UUID to set the $root (and $boot) variables in grub.

GRUB_DISABLE_UUID=true probably should imply GRUB_DISABLE_LINUX_UUID=true also
I think. But I guess is OK to have separate options and the user could set both
if want to disable using the UUID for Linux and grub.

Another option is to extend GRUB_DISABLE_LINUX_UUID semantics and don't add
search commands if this is set to true, but I'm not sure if that's correct.

> Daniel
> 

Best regards,
-- 
Javier Martinez Canillas
Software Engineer - Desktop Hardware Enablement
Red Hat