From af1a7301c7cf8912dca03065d448c4437c5c239f Mon Sep 17 00:00:00 2001 From: Bob Paauwe Date: Thu, 18 Dec 2014 09:51:26 -0800 Subject: [PATCH] drm/i915: Only fence tiled region of object. When creating a fence for a tiled object, only fence the area that makes up the actual tiles. The object may be larger than the tiled area and if we allow those extra addresses to be fenced, they'll get converted to addresses beyond where the object is mapped. This opens up the possiblity of writes beyond the end of object. To prevent this, we adjust the size of the fence to only encompass the area that makes up the actual tiles. The extra space is considered un-tiled and now behaves as if it was a linear object. Testcase: igt/gem_tiled_fence_overflow Reported-by: Dan Hettena Signed-off-by: Bob Paauwe Reviewed-by: Daniel Vetter Cc: stable@vger.kernel.org Signed-off-by: Jani Nikula --- drivers/gpu/drm/i915/i915_gem.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index b4a4f36..5f61482 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -3148,6 +3148,13 @@ static void i965_write_fence_reg(struct drm_device *dev, int reg, u32 size = i915_gem_obj_ggtt_size(obj); uint64_t val; + /* Adjust fence size to match tiled area */ + if (obj->tiling_mode != I915_TILING_NONE) { + uint32_t row_size = obj->stride * + (obj->tiling_mode == I915_TILING_Y ? 32 : 8); + size = (size / row_size) * row_size; + } + val = (uint64_t)((i915_gem_obj_ggtt_offset(obj) + size - 4096) & 0xfffff000) << 32; val |= i915_gem_obj_ggtt_offset(obj) & 0xfffff000; -- 2.7.4