[Intel-gfx] Patch "drm/i915: Fix unsafe loop iteration over vma whilst unbinding them" has been added to the 3.14-stable tree

[gregkh at linuxfoundation.org]

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

    drm/i915: Fix unsafe loop iteration over vma whilst unbinding them

to the 3.14-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-fix-unsafe-loop-iteration-over-vma-whilst-unbinding-them.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable at vger.kernel.org> know about it.


>From daniel.vetter at ffwll.ch  Tue Jun  3 23:13:34 2014
From: Daniel Vetter <daniel.vetter at ffwll.ch>
Date: Wed, 21 May 2014 11:07:24 +0200
Subject: drm/i915: Fix unsafe loop iteration over vma whilst unbinding them
To: stable at vger.kernel.org
Cc: Intel Graphics Development <intel-gfx at lists.freedesktop.org>, Chris Wilson <chris at chris-wilson.co.uk>, Ben Widawsky <ben at bwidawsk.net>, Daniel Vetter <daniel.vetter at ffwll.ch>
Message-ID: <1400663245-15601-4-git-send-email-daniel.vetter at ffwll.ch>


From: Chris Wilson <chris at chris-wilson.co.uk>

This is commit df6f783a4ef6790780a67c491897ac upstream.

On non-LLC platforms, when changing the cache level of an object, we may
need to unbind it so that prefetching across page boundaries does not
cross into a different memory domain. This requires us to unbind
conflicting vma, but we did so iterating over the objects vma in an
unsafe manner (as the list was being modified as we iterated).

The regression was introduced in
commit 3089c6f239d7d2c4cb2dd5c353e8984cf79af1d7
Author: Ben Widawsky <ben at bwidawsk.net>
Date:   Wed Jul 31 17:00:03 2013 -0700

    drm/i915: make caching operate on all address spaces
apparently as far back as v3.12-rc1, but it has only just begun to
trigger real world bug reports.

Reported-and-tested-by: Nikolay Martynov <mar.kolya at gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76384
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Ben Widawsky <ben at bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 drivers/gpu/drm/i915/i915_gem.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3529,7 +3529,7 @@ int i915_gem_object_set_cache_level(stru
 {
 	struct drm_device *dev = obj->base.dev;
 	drm_i915_private_t *dev_priv = dev->dev_private;
-	struct i915_vma *vma;
+	struct i915_vma *vma, *next;
 	int ret;
 
 	if (obj->cache_level == cache_level)
@@ -3540,7 +3540,7 @@ int i915_gem_object_set_cache_level(stru
 		return -EBUSY;
 	}
 
-	list_for_each_entry(vma, &obj->vma_list, vma_link) {
+	list_for_each_entry_safe(vma, next, &obj->vma_list, vma_link) {
 		if (!i915_gem_valid_gtt_space(dev, &vma->node, cache_level)) {
 			ret = i915_vma_unbind(vma);
 			if (ret)


Patches currently in stable-queue which might be from daniel.vetter at ffwll.ch are

queue-3.14/drm-i915-don-t-warn-nor-handle-unexpected-hpd-interrupts-on-gmch-platforms.patch
queue-3.14/drm-i915-fix-unsafe-loop-iteration-over-vma-whilst-unbinding-them.patch
queue-3.14/drm-i915-disable-self-refresh-for-untiled-fbs-on-i915gm.patch
queue-3.14/drm-i915-don-t-check-gmch-state-on-inherited-configs.patch
queue-3.14/drm-i915-break-encoder-crtc-link-separately-in-intel_sanitize_crtc.patch
queue-3.14/drm-i915-quirk-invert-brightness-for-acer-aspire-5336.patch
queue-3.14/drm-i915-move-power-domain-init-earlier-during-system-resume.patch