[PATCH 4.18 165/171] drm/i915: Compare users 64b GTT offset even on 32b

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>

commit 085603287452fc96376ed4888bf29f8c095d2b40 upstream.

Beware mixing unsigned long constants and 64b values, as on 32b the
constant will be zero extended and discard the high 32b when used as
a mask!

Reported-by: Sergii Romantsov <sergii.romantsov@xxxxxxxxxxxxxxx>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108282
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Matthew Auld <matthew.auld@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20181025091823.20571-2-chris@xxxxxxxxxxxxxxxxxx
(cherry picked from commit 6fc4e48f9ed46e9adff236a0c350074aafa3b7fa)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/gpu/drm/i915/gvt/gtt.h             |    1 -
 drivers/gpu/drm/i915/i915_gem_execbuffer.c |    2 +-
 drivers/gpu/drm/i915/i915_gem_gtt.h        |    2 ++
 3 files changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/i915/gvt/gtt.h
+++ b/drivers/gpu/drm/i915/gvt/gtt.h
@@ -35,7 +35,6 @@
 #define _GVT_GTT_H_
 
 #define I915_GTT_PAGE_SHIFT         12
-#define I915_GTT_PAGE_MASK		(~(I915_GTT_PAGE_SIZE - 1))
 
 struct intel_vgpu_mm;
 
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -449,7 +449,7 @@ eb_validate_vma(struct i915_execbuffer *
 	 * any non-page-aligned or non-canonical addresses.
 	 */
 	if (unlikely(entry->flags & EXEC_OBJECT_PINNED &&
-		     entry->offset != gen8_canonical_addr(entry->offset & PAGE_MASK)))
+		     entry->offset != gen8_canonical_addr(entry->offset & I915_GTT_PAGE_MASK)))
 		return -EINVAL;
 
 	/* pad_to_size was once a reserved field, so sanitize it */
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -49,6 +49,8 @@
 #define I915_GTT_PAGE_SIZE I915_GTT_PAGE_SIZE_4K
 #define I915_GTT_MAX_PAGE_SIZE I915_GTT_PAGE_SIZE_2M
 
+#define I915_GTT_PAGE_MASK -I915_GTT_PAGE_SIZE
+
 #define I915_GTT_MIN_ALIGNMENT I915_GTT_PAGE_SIZE
 
 #define I915_FENCE_REG_NONE -1