[Intel-gfx] [PATCH v3 19/19] drm/i915: Add fault injection support

[Imre Deak]

On Wed, 2016-03-16 at 12:44 +0000, Chris Wilson wrote:
> On Wed, Mar 16, 2016 at 02:12:35PM +0200, Imre Deak wrote:
> > On Wed, 2016-03-16 at 12:00 +0000, Chris Wilson wrote:
> > > On Wed, Mar 16, 2016 at 01:39:08PM +0200, Imre Deak wrote:
> > > > Add support for forcing an error at selected places in the
> > > > driver.
> > > > As an
> > > > example add 4 options to fail during driver loading.
> > > > 
> > > > Requested by Chris.
> > > > 
> > > > v2:
> > > > - Add fault point for modeset initialization
> > > > - Print debug message when injecting an error
> > > > v3:
> > > > - Rename inject_fault to inject_load_failure, rename the
> > > > related
> > > > macros
> > > >   and helper accordingly (Chris)
> > > > - Use a counter instead of a mask to identify the failure point
> > > > (Daniel)
> > > > - Mark the module option as _unsafe and keep i915_params
> > > > ordered
> > > > (Joonas)
> > > 
> > > Now that you have something so simple to use, putting a failure
> > > point
> > > at
> > > the start and end of each init_func is trivial (to test the local
> > > unwind
> > > in each function as well as the global unwind).
> > 
> > Ok can do this, but again preferably as a follow-up:
> > i915_load_modeset_init() has pre-existing issues, the last thing I
> > checked was some running work item that gets scheduled after we
> > removed
> > the module already (maybe the eDP VDD work). I'll track down that
> > and
> > try to clean up the rest of problems I see in
> > i915_load_modeset_init();
> > with those I could add the additional checkpoints you suggest.
> 
> Should we expose the injection fault count so that we can automate
> repeating the module reload for the right number of cycles?

Yes, can add that.

--Imre

> -Chris
>