[Intel-gfx] [PATCH 3/3] drm/i915: Don't taint when using fault injection

[Chris Wilson]

Quoting Michał Winiarski (2020-07-06 15:01:25)
> From: Michał Winiarski <michal.winiarski at intel.com>
> 
> It is not really unexpected to hit wedge on init this way.
> We're already downgrading error printk when running with fault injection,
> let's use the same approach for CI tainting.
> 
> Signed-off-by: Michał Winiarski <michal.winiarski at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Petri Latvala <petri.latvala at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_utils.h | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_utils.h b/drivers/gpu/drm/i915/i915_utils.h
> index 82fada1e7552..d84c23592942 100644
> --- a/drivers/gpu/drm/i915/i915_utils.h
> +++ b/drivers/gpu/drm/i915/i915_utils.h
> @@ -438,7 +438,9 @@ static inline const char *enableddisabled(bool v)
>  
>  static inline void __add_taint_for_CI(unsigned int taint)
>  {
> -       add_taint(taint, LOCKDEP_STILL_OK);
> +       /* Failures that occur during fault injection testing are expected */
> +       if (!i915_error_injected())
> +               add_taint(taint, LOCKDEP_STILL_OK);
>  }

And I think this is better in add_taint_for_CI(). If we hit the
GEM_BUG_ON() we should always add the taint, as that trace dump is a
one-shot affair.
-Chris