Re: Windows side agrees that lowmem corruption is a problem too

[Ondrej Zary <linux@rainbow-software.org>]

On Tuesday 08 June 2010 21:08:48 Ingo Molnar wrote:
> * H. Peter Anvin <hpa@zytor.com> wrote:
> > On 06/08/2010 11:28 AM, Yuhong Bao wrote:
> > > Adding mingo and gregkh to CC list.
> > >
> > >> Remember the lowmem corruption problems that lead the code that
> > >> displays this to be added to Linux:> AMI BIOS detected: BIOS may
> > >> corrupt low RAM, working around it.> which was IMO way too broad. Good
> > >> news, the Windows side agree that this is a problem too:>
> > >> http://www.microsoft.com/whdc/system/platform/firmware/mem-corrupt.msp
> > >>x>> Yuhong Bao
> >
> > Hardly "way too broad".  I'm starting to think we should enable it
> > unconditionally, given the number of machines which have exhibited that
> > problem.  As shown in the whitepaper, Vista/Win7 even avoid using
> > < 1 MB for a lot of things, presumably for this reason.
> >
> > If it only was suspend, it would be one thing, but from what I've seen
> > it has been known to happen at other times too (e.g. HDMI cable
> > insertion!)
>
> Yep, patterns of some silly OSD bitmap showed up in one of the corruption -
> firmware displaying a 'you inserted a cable' kind of icon somewhere and
> messing up the SMM code or so ...
>
> I agree that dis-using <1M by default is probably the sanest option.

But please limit it to newer systems only (DMI present && year > 200?). There 
are many old machines running fine. Losing 1MB from 16MB is a bad thing.

-- 
Ondrej Zary