Patch "drm/i915: Avoid pointer arithmetic in calculating plane surface offset" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

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

    drm/i915: Avoid pointer arithmetic in calculating plane surface offset

to the 4.4-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-avoid-pointer-arithmetic-in-calculating-plane-surface-offset.patch
and it can be found in the queue-4.4 subdirectory.

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


>From 44eb0cb9620c6a53ec8e7073262e2af8079b727f Mon Sep 17 00:00:00 2001
From: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date: Fri, 30 Oct 2015 13:26:15 +0200
Subject: drm/i915: Avoid pointer arithmetic in calculating plane surface offset
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Mika Kuoppala <mika.kuoppala@linux.intel.com>

commit 44eb0cb9620c6a53ec8e7073262e2af8079b727f upstream.

VMA offsets are 64 bits. Plane surface offsets are in ggtt and
the hardware register to set this is thus 32 bits. Be explicit
about these and convert carefully to from vma to final size.

This will make sparse happy by not creating 32bit pointers out
of 64bit vma offsets.

Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446204375-29831-1-git-send-email-mika.kuoppala@intel.com
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/i915/intel_display.c |   16 +++++++++-------
 drivers/gpu/drm/i915/intel_drv.h     |    6 +++---
 drivers/gpu/drm/i915/intel_sprite.c  |    2 +-
 3 files changed, 13 insertions(+), 11 deletions(-)

--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2950,13 +2950,13 @@ u32 intel_fb_stride_alignment(struct drm
 	}
 }
 
-unsigned long intel_plane_obj_offset(struct intel_plane *intel_plane,
-				     struct drm_i915_gem_object *obj,
-				     unsigned int plane)
+u32 intel_plane_obj_offset(struct intel_plane *intel_plane,
+			   struct drm_i915_gem_object *obj,
+			   unsigned int plane)
 {
 	const struct i915_ggtt_view *view = &i915_ggtt_view_normal;
 	struct i915_vma *vma;
-	unsigned char *offset;
+	u64 offset;
 
 	if (intel_rotation_90_or_270(intel_plane->base.state->rotation))
 		view = &i915_ggtt_view_rotated;
@@ -2966,14 +2966,16 @@ unsigned long intel_plane_obj_offset(str
 		view->type))
 		return -1;
 
-	offset = (unsigned char *)vma->node.start;
+	offset = vma->node.start;
 
 	if (plane == 1) {
 		offset += vma->ggtt_view.rotation_info.uv_start_page *
 			  PAGE_SIZE;
 	}
 
-	return (unsigned long)offset;
+	WARN_ON(upper_32_bits(offset));
+
+	return lower_32_bits(offset);
 }
 
 static void skl_detach_scaler(struct intel_crtc *intel_crtc, int id)
@@ -3099,7 +3101,7 @@ static void skylake_update_primary_plane
 	u32 tile_height, plane_offset, plane_size;
 	unsigned int rotation;
 	int x_offset, y_offset;
-	unsigned long surf_addr;
+	u32 surf_addr;
 	struct intel_crtc_state *crtc_state = intel_crtc->config;
 	struct intel_plane_state *plane_state;
 	int src_x = 0, src_y = 0, src_w = 0, src_h = 0;
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1177,9 +1177,9 @@ void intel_modeset_preclose(struct drm_d
 int skl_update_scaler_crtc(struct intel_crtc_state *crtc_state);
 int skl_max_scale(struct intel_crtc *crtc, struct intel_crtc_state *crtc_state);
 
-unsigned long intel_plane_obj_offset(struct intel_plane *intel_plane,
-				     struct drm_i915_gem_object *obj,
-				     unsigned int plane);
+u32 intel_plane_obj_offset(struct intel_plane *intel_plane,
+			   struct drm_i915_gem_object *obj,
+			   unsigned int plane);
 
 u32 skl_plane_ctl_format(uint32_t pixel_format);
 u32 skl_plane_ctl_tiling(uint64_t fb_modifier);
--- a/drivers/gpu/drm/i915/intel_sprite.c
+++ b/drivers/gpu/drm/i915/intel_sprite.c
@@ -195,7 +195,7 @@ skl_update_plane(struct drm_plane *drm_p
 	int pixel_size = drm_format_plane_cpp(fb->pixel_format, 0);
 	const struct drm_intel_sprite_colorkey *key =
 		&to_intel_plane_state(drm_plane->state)->ckey;
-	unsigned long surf_addr;
+	u32 surf_addr;
 	u32 tile_height, plane_offset, plane_size;
 	unsigned int rotation;
 	int x_offset, y_offset;


Patches currently in stable-queue which might be from mika.kuoppala@linux.intel.com are

queue-4.4/drm-i915-avoid-pointer-arithmetic-in-calculating-plane-surface-offset.patch