Re: [PATCH] drm/i915: Move ioremap_wc tracking onto VMA

Chris Wilson
2016-04-15T10:00:39Z

On Fri, Apr 15, 2016 at 10:40:42AM +0100, Tvrtko Ursulin wrote:
>
> On 13/04/16 16:12, Chris Wilson wrote:
> >On Wed, Apr 13, 2016 at 03:47:58PM +0100, Chris Wilson wrote:
> >>+ /* We also want to clear any cached iomaps as they wrap vmap */
> >>+ list_for_each_entry_safe(vma, next,
> >>+ &dev_priv->ggtt.base.inactive_list, vm_link)
> >>+ if (vma->iomap && i915_vma_unbind(vma) == 0)
> >>+ freed_pages += vma->node.size >> PAGE_SHIFT;
> >
> >Use after free. I need to store the page count in a local before calling
> >unbind.
>
> Waiting for respin. :)
>
> Also, shouldn't the patch which adds the size argument to
> io_mapping_map_wc be in this series?

It was, this was just an update to patch 2. The delta here is just
unsigned long count = vma->node.size >> PAGE_SHIFT;
if (vma->iomap && i915_vma_unbind(vma) == 0)
freed_pages += count;
-Chris

--
Chris Wilson, Intel Open Source Technology Centre