[PATCH v2 5/6] virtio-gpu: add basic prime support

[Gerd Hoffmann]

> > +int virtgpu_gem_prime_mmap(struct drm_gem_object *obj,
> > +		       struct vm_area_struct *area)
> > +{
> > +	WARN_ONCE(1, "not implemented");
> > +	return ENOSYS;
> 
> This can get called by userspace, so please don't WARN here. Also missing
> negate sign:
> 
> 	return -ENOSYS;

Hmm now checkpatch throws a warning at me:

<quote>
   WARNING: ENOSYS means 'invalid syscall nr' and nothing else
   #12: FILE: drivers/gpu/drm/virtio/virtgpu_prime.c:70:
   +       return -ENOSYS;
</quote>

I guess I should use something else then (here and elsewhere in the
file)?  Maybe -EINVAL?  Other suggestions?

thanks,
  Gerd