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SubjectDMA controller freezes Linux?

I am not sure if this is relevant to this kernel-related list but
I have noticed a very strange problem and after seeing so many talks about
hardware on this list, I'd like to share this problem in hope someone
might be able to shed a light on this.

It seems I have found a hardware-dependent software solution for
immediately freezing Linux (same happens under NT, which I installed
for testing this, btw).

*** Description: As usual, the computer boots fine under Linux,
all drivers (including the soundcard and EISA SCSI) are loaded fine. Now,
at this point, if I try to do _anything_ with the soundcard (with the
parts of it using DMA), Linux freezes immediately.

The thing is that I think I know (IMHO) the reason why this is
happening.

On my former motherboard (The excellent ASUS PCI/E P54NP4, bigger
brother to the board on which Linux-SMP was originally developped), I once
lost all my CMOS settings and I ended up having the following BIOS
setting: "DMA mode: Extended", instead of "DMA mode: Compatible". I then
started running into this "soundcard-freezes-any-OS" problem until I
discovered the source and set "DMA mode" back to "compatible". FYI, my
soundcard uses DMA channels 0 and 3 and my EISA SCSI adapter uses DMA
channel 5 and both cards exhibit the problem what something touches their
DMA channels.

Now, I got this new motherboard (EVEREX, PCI/EISA Dual PPro, 1
CPU) and the problem happens again: instant Freeze under Linux and NT,
except this time I don't have any nice "DMA mode" changeable setting in my
BIOS. :(

This is probably the result of a poor design on the motherboard or
is it the result of a more general trend that will tend to drop support
for DMA-capable cards in out mb's? Anyone care to shed any info on this?
That would be really apreciated (maybe that could save me the trouble of
sending that expensive board back to where it came from..). Thanks for
reading this.

PS: Happy BDay Linux! :)

,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,._.,-*~'`^`'~*-,
Vincent S. Cojot, Computer Engineering. STEP project. _.,-*~'`^`'~*-,._.,-*~
Ecole Polytechnique de Montreal, Comite Micro-Informatique. _.,-*~'`^`'~*-,.
Linux Xview/OpenLook resources page _.,-*~'`^`'~*-,._ coyote@info.polymtl.ca
http://www.info.polymtl.ca/~coyote _.,-*~'`^`'~*-,._ coyote@step.polymtl.ca

They cannot scare me with their empty spaces
Between stars - on stars where no human race is
I have it in me so much nearer home
To scare myself with my own desert places. - Robert Frost




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