[Intel-gfx] [PATCH igt 3/9] igt/drv_hangman: Inject a true hang

[Chris Wilson]

On Wed, Dec 16, 2015 at 10:02:27AM +0100, Daniel Vetter wrote:
> On Sat, Dec 12, 2015 at 08:02:49PM +0000, Chris Wilson wrote:
> > Wean drv_hangman off the atrocious stop_rings and use a real GPU hang
> > instead.
> > 
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> 
> Doesn't this kill pre-gen6? Or at least anything where we don't have
> proper hang recovery ... Lack of that is why I've done the original
> stop_rings fun.

Originally, igt_hang_ring required gen >= 5, but since that Ville has
been working hard on getting reset support working for gen3 and gen4,
now we query the kernel as to whether it can reset the device. So by
switching over we lose testing of simulated hangs and recovery code (or 
KMS handling during wedged) for gen2.

It is a loss in test coverage, but the benefit is that we can remove the
hang injection code from the kernel. And that is a tradeoff I am willing
to make.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre