drm/i915: Be defensive when cleaning up i915_gem_internal pages

If we abort the i915_gem_internal get_pages, we mark the failing sg as
the last. However, that means we iterate upto and including the failing
sg element and results in us trying to free the unallocated sg_page().

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170131104630.3074-1-chris@chris-wilson.co.uk
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
This commit is contained in:
Chris Wilson 2017-01-31 10:46:30 +00:00
parent 9b51b105f2
commit 4703b0472e
1 changed files with 5 additions and 2 deletions

View File

@ -35,8 +35,10 @@ static void internal_free_pages(struct sg_table *st)
{
struct scatterlist *sg;
for (sg = st->sgl; sg; sg = __sg_next(sg))
__free_pages(sg_page(sg), get_order(sg->length));
for (sg = st->sgl; sg; sg = __sg_next(sg)) {
if (sg_page(sg))
__free_pages(sg_page(sg), get_order(sg->length));
}
sg_free_table(st);
kfree(st);
@ -116,6 +118,7 @@ i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj)
return st;
err:
sg_set_page(sg, NULL, 0, 0);
sg_mark_end(sg);
internal_free_pages(st);
return ERR_PTR(-ENOMEM);