Patch "drm/i915: Don't touch NULL sg on i915_gem_object_get_pages_gtt() error" has been added to the 4.8-stable tree

This is a note to let you know that I've just added the patch titled

drm/i915: Don't touch NULL sg on i915_gem_object_get_pages_gtt() error

to the 4.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:

     drm-i915-don-t-touch-null-sg-on-i915_gem_object_get_pages_gtt-error.patch

and it can be found in the queue-4.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Chris Wilson <[email protected]>
Date: Mon, 14 Nov 2016 11:29:30 +0000
Subject: drm/i915: Don't touch NULL sg on i915_gem_object_get_pages_gtt() error

From: Chris Wilson <[email protected]>

commit 2420489bcb8910188578acc0c11c75445c2e4b92 upstream.

On the DMA mapping error path, sg may be NULL (it has already been marked as the last scatterlist entry), and we should avoid dereferencing it again.

---
 drivers/gpu/drm/i915/i915_gem.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

@@ -2540,7 +2540,7 @@ i915_gem_object_get_pages_gtt(struct drm
 			page = shmem_read_mapping_page(mapping, i);
 			if (IS_ERR(page)) {
 				ret = PTR_ERR(page);
-				goto err_pages;
+				goto err_sg;
 			}
 		}
 #ifdef CONFIG_SWIOTLB

@@ -2583,8 +2583,9 @@ i915_gem_object_get_pages_gtt(struct drm
 
 	return 0;
 
-err_pages:
+err_sg:
 	sg_mark_end(sg);
+err_pages:
 	for_each_sgt_page(page, sgt_iter, st)
 		put_page(page);
 	sg_free_table(st);

Patches currently in stable-queue which might be from [email protected] are

queue-4.8/drm-i915-don-t-touch-null-sg-on-i915_gem_object_get_pages_gtt-error.patch queue-4.8/drm-i915-drop-the-struct_mutex-when-wedged-or-trying-to-reset.patch