Re: [PATCH] memdisk plus lnxboot extension

[Robert Millan]

On Wed, Jan 23, 2008 at 01:17:43AM +0800, Bean wrote:
> On Jan 23, 2008 12:51 AM, Robert Millan <address@hidden> wrote:
> > I don't like this very much.  We don't have grub-mkimage options to 
> > concatenate
> > it with boot.img, so why with lnxboot.img ?
> 
> The reason for new option is that the length of core.img needs to
> stored in lnxboot.img. Previously, i calculate the size using
> information in core.img header, but now there is issue, for example,
> 
> 1.
> kernel lnxboot.img
> initrd core.img
> 
> 2.
> cat lnxboot.img core.img > grub2.bin
> kernel grub2.bin
> initrd memdisk
> 
> 1 and 2 looks the same to lnxboot header, it can't decide initrd is
> used as memdisk or core.img. However, 1 may not be that useful after
> all, we can disable this kind of usage.

I didn't know you had 1 in mind.  Yes, I think it's better to restrict us
to 2 for now.  I don't really see a big benefit in 2 vs just using
"grub-mkimage -m", but I suppose if it's not too intrusive it doesn't harm.

> > Also, I can only think of very specific situations in which this interface
> > would be useful (that is, when firmware has only a linux loader).  It makes
> > sense to me as a compatibility layer, yes.
> >
> > But it seems you want it as a general-purpose option; for that, why not make
> > it saner like multiboot?  I don't think it's a good idea to compromise our
> > boot semantics because of the ones legacy Linux has.
> 
> is multiboot support memdisk or something similar ?

I'm not very familiar with multiboot, but it supports modules (an arbitrary
number of them, I think).  Then again, we still need a use case before adding
a feature.  The obvious use case for having lnxboot is booting from firmware
that only supports booting Linux, but for other stuff I still don't see it.

I mean, the initial purpose of memdisk was that you could _embed_ data in
core.img itself.  Using it as a loader feature sounds a bit contradictory to
me... perhaps if you explain what situations do you have in mind where this
would be helpful, I'd understand your point better.

-- 
Robert Millan

<GPLv2> I know my rights; I want my phone call!
<DRM> What use is a phone call… if you are unable to speak?
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