It looks like gen2 has a peculiar interleaved 2-row inter-tile layout. Probably inherited from i81x which had 2kb tiles (which naturally fit an even-number-of-tile-rows scheme to fit onto 4kb pages). There is no other mention of this in any docs (also not in the Intel internal documention according to Chris Wilson). Problem manifests itself in corruptions in the second half of the last tile row (if the bo has an odd number of tiles). Which can only happen with relaxed tiling (introduced in a00b10c360b35d6431a9). So reject set_tiling calls that don't satisfy this constrain to prevent broken userspace from causing havoc. While at it, also check the size for newer chipsets. LKML: https://lkml.org/lkml/2011/2/19/5 Reported-by: Indan Zupancic <indan@xxxxxx> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx> --- drivers/gpu/drm/i915/i915_gem_tiling.c | 16 +++++++++++++++- 1 files changed, 15 insertions(+), 1 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c index 22a32b9..79a04fd 100644 --- a/drivers/gpu/drm/i915/i915_gem_tiling.c +++ b/drivers/gpu/drm/i915/i915_gem_tiling.c @@ -184,7 +184,7 @@ i915_gem_detect_bit_6_swizzle(struct drm_device *dev) static bool i915_tiling_ok(struct drm_device *dev, int stride, int size, int tiling_mode) { - int tile_width; + int tile_width, tile_height; /* Linear is always fine */ if (tiling_mode == I915_TILING_NONE) @@ -215,6 +215,20 @@ i915_tiling_ok(struct drm_device *dev, int stride, int size, int tiling_mode) } } + if (IS_GEN2(dev) || + (tiling_mode == I915_TILING_Y && HAS_128_BYTE_Y_TILING(dev))) + tile_height = 32; + else + tile_height = 8; + /* i8xx is strange: It has 2 interleaved rows of tiles, so needs an even + * number of tile rows. */ + if (IS_GEN2(dev)) + tile_height *= 2; + + /* Size needs to be aligned to a full tile row */ + if (size & (tile_height * stride - 1)) + return false; + /* 965+ just needs multiples of tile width */ if (INTEL_INFO(dev)->gen >= 4) { if (stride & (tile_width - 1)) -- 1.7.4.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
