Re: [PATCH 2/2] efi: Distinguish between "remaining space" andactually used space

From: Matthew Garrett
Date: Wed Apr 03 2013 - 13:20:52 EST


On Wed, 2013-04-03 at 18:12 +0100, Matt Fleming wrote:

> The solution you're proposing has the same downsides as 3) - we risk
> having to tweak things either way. The difference is that in the case of
> 3) the tweaking is adding entries to the whitelist, whereas tweaking
> your solution has more chance of introducing further unwanted
> regressions because you'd be tweaking an algorithm, an algorithm that
> relies on the internal implementation of the variable storage code.

We *risk* having to tweak things, and we fail on the side of safety.

> > Dealing with firmware is hard. This fixes (1) without leaving us with
> > (2), which seems like a net win.
>
> I'm not convinced that implementing 3) would inevitably lead to 2),
> provided that we apply a bit of common sense when adding entries. I'm
> not advocating some kind of flag day where we add umpteen machines to
> the whitelist.
>
> For reference, I just pushed two patches to the 'whitelist' branch at,
>
> git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi.git
>
> which should hopefully illustrate the kind of thing that I'm talking about.

I don't think that works. People are complaining that we broke some
Thinkpads as well, but we also have reports that Thinkpads can be
bricked if we use too much space.

--
Matthew Garrett | mjg59@xxxxxxxxxxxxx
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