[ 3.8.y.z extended stable ] Patch "drm/i915: fix up ring cleanup for the i830/i845 CS tlb w/a" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    drm/i915: fix up ring cleanup for the i830/i845 CS tlb w/a

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.6.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From cf9f2fc81448a358349320311ccb25bb6016749f Mon Sep 17 00:00:00 2001
From: Daniel Vetter <daniel.vetter at ffwll.ch>
Date: Fri, 5 Jul 2013 23:39:50 +0200
Subject: drm/i915: fix up ring cleanup for the i830/i845 CS tlb w/a

commit aaf8a5167291b65e9116cb8736d862965b57c13a upstream.

It's not a good idea to also run the pipe_control cleanup.

This regression has been introduced whith the original cs tlb w/a in

commit b45305fce5bb1abec263fcff9d81ebecd6306ede
Author: Daniel Vetter <daniel.vetter at ffwll.ch>
Date:   Mon Dec 17 16:21:27 2012 +0100

    drm/i915: Implement workaround for broken CS tlb on i830/845

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=64610
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/gpu/drm/i915/intel_ringbuffer.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 42ff97d..27f810f 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -486,9 +486,6 @@ cleanup_pipe_control(struct intel_ring_buffer *ring)
 	struct pipe_control *pc = ring->private;
 	struct drm_i915_gem_object *obj;

-	if (!ring->private)
-		return;
-
 	obj = pc->obj;

 	kunmap(sg_page(obj->pages->sgl));
@@ -496,7 +493,6 @@ cleanup_pipe_control(struct intel_ring_buffer *ring)
 	drm_gem_object_unreference(&obj->base);

 	kfree(pc);
-	ring->private = NULL;
 }

 static int init_render_ring(struct intel_ring_buffer *ring)
@@ -567,7 +563,10 @@ static void render_ring_cleanup(struct intel_ring_buffer *ring)
 	if (HAS_BROKEN_CS_TLB(dev))
 		drm_gem_object_unreference(to_gem_object(ring->private));

-	cleanup_pipe_control(ring);
+	if (INTEL_INFO(dev)->gen >= 5)
+		cleanup_pipe_control(ring);
+
+	ring->private = NULL;
 }

 static void
--
1.8.1.2