Subject: Re: Disk driver related problems?
To: Mark White <>
From: Manuel Bouyer <>
List: port-i386
Date: 11/20/2000 23:40:18
On Mon, Nov 20, 2000 at 09:56:31PM +0000, Mark White wrote:
> I have a couple of problems which are probably related - can
> anybody shed some light on them?  I am running NetBSD 1.5
> BETA2, on a K6/2-550 (Aladdin MB).

Do you know which IDE controller is has ?

> 1. The drive access light is on when the system boots, and
> remains on until the CDROM [samsung 40x] is first accessed.
> Doesn't matter if there's a disc in there - just cat
> /dev/cd0a will do.  Once this is done, light resumes normal
> function.

Yes, I see it too on occasion. This shouldn't cause any harm

> 2. Various DMA problems.  CD doesn't work at all unless
> accessed in PIO mode - this I gather is often the case for

Yes, this is very common for CDs

> CDs anyway - but the parallel port can't be used with DMA
> either [system hangs if you try].  Both HDDs [fujitsu 8.4
> and maxtor 2.5] and the ZIP drive seem to work in DMA mode.

I don't think NetBSD supports DMA for the parallel port.

> The system virtually stops when data is being written to
> PIO parallel port, so this is bad.
> 3. Crashes.  On 3 occasions the system has totally frozen
> while I've not been anywhere near it, without leaving
> anything in the logs.  On one of these occasions I tried
> network access to see if it was X that crashed; it didn't
> respond.

I may be in debugger, if you're running X you won't see the db> prompt.
You can try to have the system dump a core and reboot (this assumes your swap
partition is as last as large as your RAM): 'sysctl -w ddb.onpanic=0'
and wait for it to crash. Another solution is a serial console.

Manuel Bouyer, LIP6, Universite Paris VI.