Re: 2.4.21-pre4: PDC ide driver problems with shared interrupts

[Stephan von Krawczynski <skraw@ithnet.com>]

On 05 Feb 2003 12:16:02 +0100
Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:

> 
> > Okay, I had to watch for it a bit longer and it turns out that the kernel
> > PDC driver has a problem in this shared interrupt setup. When loads get
> > high it seems to run into some timing problem which causes things like:
> > 
> > Feb  4 01:02:22 admin kernel: hde: dma_intr: status=0xd0 { Busy }
> > Feb  4 01:02:22 admin kernel: 
> > Feb  4 01:02:22 admin kernel: PDC202XX: Primary channel reset.
> > Feb  4 01:02:22 admin kernel: ide2: reset: success
> > Feb  4 01:02:23 admin kernel: hde: status error: status=0x58 { DriveReady
> > SeekComplete DataRequest } Feb  4 01:02:23 admin kernel: 
> > Feb  4 01:02:23 admin kernel: hde: drive not ready for command
> > Feb  4 01:02:23 admin kernel: hde: status error: status=0x50 { DriveReady
> > SeekComplete } Feb  4 01:02:23 admin kernel: 
> > Feb  4 01:02:23 admin kernel: hde: no DRQ after issuing WRITE
> > Feb  4 01:02:23 admin kernel: hde: status timeout: status=0xd0 { Busy }
> > Feb  4 01:02:23 admin kernel: 
> 
> Hi Alan !
> 
> I'm trying to get some sense out of the above report as it seem to match
> a problem a user reported me as well. It's interesting because it's
> apparently running UP, so it's not the SMP race found by Ross. It's
> definitely a problem with shared interrupt though.

Hello Benjamin,

I have to give a short note on this one:
indeed is the system currently running with a single CPU, _but_ since it is a
dual-mb the kernel is already compiled for SMP. It is started with "nosmp"
option though. I wanted to mention this not knowing if it is important for the
codepath.

-- 
Regards,
Stephan