[Intel-gfx] [PATCH 3/3] drm/i915: Stop ignoring failure to set up workaround batch buffers

[Chris Wilson]

Quoting Tvrtko Ursulin (2018-01-19 10:29:12)
> 
> On 19/01/2018 10:09, Chris Wilson wrote:
> > Quoting Tvrtko Ursulin (2018-01-19 10:00:05)
> >> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> >>
> >> Setting up the workaround batch buffers can fail either due programming
> >> errors which will be caught in development, or by the inability to
> >> allocate a 4k object and pin it in GGTT at runtime.
> >>
> >> Since this is highly unlikely, and it is not deterministic to allow driver
> >> operation to continue with unknown status of workarounds, it is better to
> >> fail engine initialization explicitly under those circumstances.
> > 
> > Not entirely. Failing the driver load leaves the system without a
> > display / console. Disabling GPU execution is one response, but that
> > is likely to happen if the w/a requirement was severe enough.
> > 
> > We are not expecting to see an -EIO at this point in the init sequence
> > and all other errors abort the driver load.
> 
> Fair enough, I did not think about deeper consequences but only assumed 
> we would run without one engine. Assumptions assumptions!

It's not a bad idea :) The next time we give the init a spring clean we
may try that (minimising the impact of any specific failure).
-Chris