Re: Athlon PSE/AGP Bug

[Andrew Morton <akpm@zip.com.au>]

Andrea Arcangeli wrote:
> 
> ...
> 
> I think this is a very very minor issue, I doubt anybody ever triggered
> it in real life with linux.

It is said that the crashes cease when the `nopentium' option
is used, so it does appear that something is up.

I does seem that the nVidia driver is usually involved.

> And Gentoo is shipping a kernel with preempt and rmaps included, so it
> can crash anytime anyways, no matter how good the cpu is, so if they
> got crashes with such a kernel (maybe even with nvidia driver) that's
> normal. I was speaking today with a trusted party doing vm benchmarking
> and rmap crashes the kernel reproducibly under a stright calloc while
> swapping heavily, so clearly the implementation is still broken.

-rmap is still young.  I did some heavy stress testing on it a couple
of days ago and it was rock-solid, and performed well.

> preempt additionally will mess up all the locking into the nvidia driver as
> well. so if the combination of the two runs for some time without any
> lockup that's pure luck IMHO.

Yup.  But don't forget about the `nopentium' observations.

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