Re: Linux 2.5.3-pre1-aia1

[Andre Hedrick]

Yes,

I have a patch against 2.5.3-pre1 clean, and is up on kernel.org's upload
site, but k.o is down.  It can also be gotten off
	http://www.linuxdiskcert.org/
It is a tiny 37k patch and bzip2'd to 8k.

On Sat, 19 Jan 2002, Davide Libenzi wrote:

> On Sat, 19 Jan 2002, Andre Hedrick wrote:
> 
> > On Sat, 19 Jan 2002, Jens Axboe wrote:
> >
> > > On Sat, Jan 19 2002, Andre Hedrick wrote:
> > > > On Sat, 19 Jan 2002, Jens Axboe wrote:
> > > >
> > > > > On Fri, Jan 18 2002, Davide Libenzi wrote:
> > > > > > Guys, instead of requiring an -m8 to every user that is observing this
> > > > > > problem, isn't it better that you limit it inside the driver until things
> > > > > > gets fixed ?
> > > > >
> > > > > There is no -m8 limit, 2.5.3-pre1 + ata253p1-2 patch handles any set
> > > > > multi mode value.
> > > > >
> > > > > --
> > > > > Jens Axboe
> > > > >
> > > >
> > > > And that will generate the [lost interrupt], and I have it fixed at all
> > > > levels too now.
> > >
> > > How so? I don't see the problem.
> >
> > Unlike ATAPI which will generally send you more data than requested on
> > itw own, ATA devices do not like enjoy or play the game.  Additionally the
> > current code asks for 16 sectors, but we do not do the request copy
> > anymore, and this mean for every 4k of paging we are soliciting for 8k.
> > We only read out 4k thus the device has the the next 4k we may be wanting
> > ready.  Look at it as a dirty prefetch, but eventally the drive is going
> > to want to go south, thus [lost interrupt]
> >
> > Basically as the Block maintainer, you pointed out I am restricted to 4k
> > chunking in PIO.  You decided, in the interest of the block glue layer
> > into the driver, to force early end request per Linus's requirements to
> > return back every 4k completed to block regardless of the size of the
> > total data requested.
> >
> > For the above two condition to be properly satisfied, I have to adjust
> > and apply one driver policy make the driver behave and give the desired
> > results.  We should note this will conform with future IDEMA proposals
> > being submitted to the T committees.
> 
> That was it. By limiting the sector count request i was able to fix it.
> Do you've any permanent/not-hackish fix for this ?
> 
> 
> 
> 
> - Davide
> 
> 

Andre Hedrick
Linux Disk Certification Project                Linux ATA Development