2000-10-27 13:41:43

by Vojtech Pavlik

[permalink] [raw]
Subject: Re: Possible critical VIA vt82c686a chip bug (private question)

On Fri, Oct 27, 2000 at 02:04:58PM +0200, [email protected] wrote:

> > Interesting. If it's caused by SCSI as well (might be), then it's not
> > caused by heavy IDE activity but rather than that it could be heavy
> > BusMastering activity instead (The IDE chip does BM as well).
> >
> > I'm still wondering if it could be a Linux kernel bug (bad/concurrent
> > accesses to the i8253 registers), this has to be checked.
> >
> How sure are you that the chip is actually buggy? I ran into something
> similar a while ago, when I mixed the two arguments to an outb in a driver,
> and ended up writing MYPORT into the timer instead of 0x40 into MYPORT.

I'm *not* sure. It just looks like a reasonable explanation. It doesn't
happen on Intel chips and older VIA chips, it only happens on new VIA
chips, and the code is the same all the time. Also, it happens both with
2.2 and 2.4 kernels ...

Vojtech Pavlik
SuSE Labs