Re: AMD 760MPX DMA lockup (partly solved)

[Jan Kasprzak <kas@informatics.muni.cz>]

kernel@street-vision.com wrote:
: Well I have run this several times on my MPX, and it is fine.
:
: This is 2.4.20-pre1, dual AMD 2000MP, only difference is it is the Tyan
: version of the MPX, not the MSI.
:
: Justin

        Justin, thanks for this! I've tried 2.4.20-pre1 with your
.config (and then with my .config), and it works!

        Further investigation showed that the problem first appeared
somewhere between 2.4.20-pre2 (works for me) and 2.4.20-pre5 (has the
lock-up problem I've described). I was not able to test -pre3 and -pre4,
because these kernel died on me during boot after the
"Initializing RT netlink socket" message.

	I the bug got merged from the -ac kernels, because it is
present bot in the kernel 2.4.19-11 from RedHat "null" beta
and in 2.4.20-pre2-ac1 (altough the later crashes instead of lock-up).

Denis Vlasenko wrote:
: 
: 8 GB... Can you make it loop over much lesser size?
: 
	with 2GB it still fails. I didn't try less, because with 1GB of RAM
it would not have any effect.

: I assume removing read+lseek eliminates lockup?

	Partly. I've tried 

dd if=/dev/hda3 of=/dev/null bs=1024k, and it still causes filesystem
corruption (altough no lockup).

: Is it IDE related or not? 
: If you can test it over SCSI/NFS/ramdisk/???...

	I think it is IDE or DMA related.

: > When I switch off the DMA (hdparm -d0 /dev/hda), the problem goes away
: > (however, the disk is very slow, as expected).
: 
: At which DMA/UDMA mode it starts to fail?

	-d1 -X33 fails.

-Y.

-- 
| Jan "Yenya" Kasprzak  <kas at {fi.muni.cz - work | yenya.net - private}> |
| GPG: ID 1024/D3498839      Fingerprint 0D99A7FB206605D7 8B35FCDE05B18A5E |
| http://www.fi.muni.cz/~kas/   Czech Linux Homepage: http://www.linux.cz/ |
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