Possible mouse/ATA problems in -STABLE

[Soren Schmidt]

It seems Soren Schmidt wrote:
> > > ...
> > > "This pushed the time spent between starting the ATA command and
> > > starting the DMA engine over the hill for some controllers
> > > (especially the Silicon Image DS3112a) and caused what looked
> > > like lost interrupts."
> > > 
> > > - so possibly we need another MFC... ?
> > 
> > I think maybe we do.  Unfortunately Soeren is not working on ATA in
> > -stable.  Is there anyone else (a committer?) who can verify that this
> > analysis is correct?  Can we circulate a patch?
> 
> That change in -current doesn't not easily apply to -stable, and does
> not change the amount of time spent in interrupt at all. The change
> in current fixes total lockups of some controllers when the time
> busdma use to setup the SG list is too long.

Oh, maybe I should say that the ATA driver in -current is *very*
different from the one in stable. This makes the idea of MFC's 
moot since very little code can be moved without a rewrite. This
mandates significant testing etc since is will be like new virgin code.

-Søren