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

[Ingo Molnar <mingo@elte.hu>]

* 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.mspx>> 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.

	Ingo