[Intel-gfx] [PATCH] drm/i915: Quieten compiler warning for ctch_open()

[Chris Wilson]

Quoting Chris Wilson (2017-06-03 18:50:02)
> Sparse sees that vma may be NULL, but doesn't realise that the

s/sparse/smatch/

> constructor will set vma or flag an error. Give is a BUG_ON so it knows
> that vma is non-NULL afterwards.
> 
> drivers/gpu/drm/i915/intel_guc_ct.c:204 ctch_open() error: we previously
> assumed 'ctch->vma' could be null (see line 197)
> 
> Fixes: f8a58d639dd9 ("drm/i915/guc: Introduce buffer based cmd transport")
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
> Cc: Oscar Mateo <oscar.mateo at intel.com>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/intel_guc_ct.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_guc_ct.c b/drivers/gpu/drm/i915/intel_guc_ct.c
> index c4cbec140101..49ccf9090641 100644
> --- a/drivers/gpu/drm/i915/intel_guc_ct.c
> +++ b/drivers/gpu/drm/i915/intel_guc_ct.c
> @@ -199,6 +199,7 @@ static int ctch_open(struct intel_guc *guc,
>                 if (unlikely(err))
>                         goto err_out;
>         }
> +       GEM_BUG_ON(!ctch->vma);
>  
>         /* vma should be already allocated and map'ed */
>         base = guc_ggtt_offset(ctch->vma);
> -- 
> 2.11.0
>