1 files changed, 78 insertions, 0 deletions

diff --git a/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.17/0105-drm-i915-relative_constants_mode-race-fix.patch b/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.17/0105-drm-i915-relative_constants_mode-race-fix.patch
new file mode 100644
index 00000000..e074c3b9
--- /dev/null
+++ b/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.17/0105-drm-i915-relative_constants_mode-race-fix.patch
@@ -0,0 +1,78 @@
+From c1f4cbb7a7af1e7a02e2516bd82215fd79b9edbd Mon Sep 17 00:00:00 2001
+From: Ben Widawsky <ben@bwidawsk.net>
+Date: Mon, 12 Dec 2011 19:21:57 -0800
+Subject: [PATCH 105/165] drm/i915: relative_constants_mode race fix
+
+commit e2971bdab2b761683353da383c0fd5ac704d1cca upstream.
+
+dev_priv keeps track of the current addressing mode that gets set at
+execbuffer time. Unfortunately the existing code was doing this before
+acquiring struct_mutex which leaves a race with another thread also
+doing an execbuffer. If that wasn't bad enough, relocate_slow drops
+struct_mutex which opens a much more likely error where another thread
+comes in and modifies the state while relocate_slow is being slow.
+
+The solution here is to just defer setting this state until we
+absolutely need it, and we know we'll have struct_mutex for the
+remainder of our code path.
+
+v2: Keith noticed a bug in the original patch.
+
+Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
+Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
+Signed-off-by: Keith Packard <keithp@keithp.com>
+Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
+---
+ drivers/gpu/drm/i915/i915_gem_execbuffer.c |   29 +++++++++++++++------------
+ 1 files changed, 16 insertions(+), 13 deletions(-)
+
+diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+index b9da890..7d64f83 100644
+--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
++++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+@@ -1033,19 +1033,6 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
+                        if (INTEL_INFO(dev)->gen > 5 &&
+                            mode == I915_EXEC_CONSTANTS_REL_SURFACE)
+                                return -EINVAL;
+-
+-                       ret = intel_ring_begin(ring, 4);
+-                       if (ret)
+-                               return ret;
+-
+-                       intel_ring_emit(ring, MI_NOOP);
+-                       intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
+-                       intel_ring_emit(ring, INSTPM);
+-                       intel_ring_emit(ring,
+-                                       I915_EXEC_CONSTANTS_MASK << 16 | mode);
+-                       intel_ring_advance(ring);
+-
+-                       dev_priv->relative_constants_mode = mode;
+                }
+                break;
+        default:
+@@ -1176,6 +1163,22 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
+                }
+        }
+ 
++       if (ring == &dev_priv->ring[RCS] &&
++           mode != dev_priv->relative_constants_mode) {
++               ret = intel_ring_begin(ring, 4);
++               if (ret)
++                               goto err;
++
++               intel_ring_emit(ring, MI_NOOP);
++               intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
++               intel_ring_emit(ring, INSTPM);
++               intel_ring_emit(ring,
++                               I915_EXEC_CONSTANTS_MASK << 16 | mode);
++               intel_ring_advance(ring);
++
++               dev_priv->relative_constants_mode = mode;
++       }
++
+        trace_i915_gem_ring_dispatch(ring, seqno);
+ 
+        exec_start = batch_obj->gtt_offset + args->batch_start_offset;
+-- 
+1.7.7.6
+