Re: [PATCH] memdisk plus lnxboot extension

[Bean]

On Jan 21, 2008 7:24 AM, Robert Millan <address@hidden> wrote:
> On Sun, Dec 30, 2007 at 02:48:24PM +0100, Robert Millan wrote:
> > On Sat, Dec 29, 2007 at 05:05:16PM +0800, Bean wrote:
> > > Hi,
> > >
> > > This patch is based on robert's memdisk patch. I also modify lnxboot
> > > so that it can load the memdisk using initrd. Changes:
> >
> > I'd really like to keep this separate, and get memdisk merged first.
> >
> > I recall Marco had some objections to memdisk, so I'd like to get that 
> > sorted
> > out before we start building on it.
>
> memdisk is merged now, but as for supporting an initrd hack to load it, I'm 
> not
> sure if that's a good idea.
>
> Currently, you can do:
>
>   grub-mkimage -m filesystem -o core.img
>   cat lnxboot.img core.img > linux_image
>
> what you propose would be:
>
>   grub-mkimage -o core.img
>   cat lnxboot.img core.img > linux_image
>   [ use filesystem as initrd ]
>
> but, what is the advantage in that?  Is there any use case in which the first
> option is not good but the second is?

Some advantages of using external initrd:

1, Resolve size limit for core.img
core.img can't be too large, otherwise it doesn't fit inside
conventional memory. external initrd doesn't have this problem.

2. Easy to modify
users may not know how to create core.img, but modifying files in a,
say, tar or cpio archive is very easy. They can do simple tasks like
replacing splash image without too much knowledge of grub2.

3. Multiple configuration
We can use the same core.img, but different initrd to start grub2 with
different configuration.

-- 
Bean