[3.9-rc1] irq 16: nobody cared (was [3.9-rc1] very poor interrupt responses)

[Shawn Starr]

On Friday, March 15, 2013 12:14:28 PM Yinghai Lu wrote:
> On Fri, Mar 15, 2013 at 8:14 AM, Jiri Kosina <jkosina at suse.cz> wrote:
> > Just a datapoint -- I have put a trivial debugging patch in place, and it
> > reveals that "nobody cared" for irq 16 happens long after last
> > 
> >         I915_WRITE(GMBUS4 + reg_offset, 0);
> > 
> > has been performed in gmbus_wait_hw_status(). On the other hand, if I
> > comment out both GMBUS4 register offset writes in gmbus_wait_hw_status(),
> > then it of course falls back to GPIO bit-banging, but the "nobody cared"
> > for irq 16 is gone.
> > 
> > So it seems like something gets severely confused by the I915_WRITE to
> > GMBUS4 + reg_offset. So far this seems to have been reported solely on
> > Lenovos as far as I can see (although a completely different types), so it
> > might be some platform-specific quirk?
> > 
> > Honestly, I still don't understand how all the GMBUS stuff relates to IRQ
> > 16 at all.
> 
> that device is using
> i915 0000:00:02.0: irq 44 for MSI/MSI-X
> 
> so can you try to boot with pci=nomsi?

I can try disabling MSI with 3.9.0-0.rc2.git0.4.fc20. -rc3 is not yet 
available in rawhide.

thanks,
Shawn
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/dri-devel/attachments/20130317/10b7901b/attachment.html>