grub / grub2 conflicts

[Matthew Garrett]

On Mon, Sep 19, 2011 at 02:53:11PM -0400, Doug Ledford wrote:

> This is incorrect.  The whole reason the stage1.5 portion is an fs 
> compatible reader is so that you can update the stage2 file and it 
> will pick the changes up without needing to be reinstalled.  This is 
> also born out by the fact that on package update, there is no %post 
> action in the spec to reinstall the mbr and stage 1.5 files even 
> though the stage2 file likely just changed.

We never update the stage 2 file without reinstalling the mbr and stage 
1.5. The output of rpm -qf grub may be instructive.

> > I don't see where compatibility issues come into it. If
> > you're using the code as you're meant to use the code then you'll
> > always
> > be safe. If you're not, it's not guaranteed to be safe.
> 
> Like I said, not true.  The grub package is designed to be updateable 
> without requiring an mbr reinstall.  What's more is I had a look at 
> the stage1.[hS] files in the grub shipped in FC-1 and RHEL-5, and just 
> like I said, they are indeed binary compatible.  So even if the grub 
> user space application pulls its MBR from a statically linked copy of 
> the MBR, it will still work with pretty much any stage1.5 or stage2 
> you find in a guest.

The grub package (as provided in Fedora) is not designed for that. This 
would be a much easier discussion to have if you stopped describing 
things that are manifestly true as "not true". And while it is the case 
that grub *is* binary compatible between every version we've ever 
released, it is *not* guaranteed that that remains true, or even that 
it's true between us and any distribution that may be installed in a 
guest.

-- 
Matthew Garrett | mjg59 at srcf.ucam.org