From: Chris Wilson Date: Thu, 12 Feb 2015 07:53:18 +0000 (+0000) Subject: drm/i915: Check obj->vma_list under the struct_mutex X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=6c31a614c43ae274546f736b2a33363e149c3dc2;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git drm/i915: Check obj->vma_list under the struct_mutex When we walk the list of vma, or even for protecting against concurrent framebuffer creation, we must hold the struct_mutex or else a second thread can corrupt the list as we walk it. Fixes regression from commit d7f46fc4e7323887494db13f063a8e59861fefb0 Author: Ben Widawsky Date: Fri Dec 6 14:10:55 2013 -0800 drm/i915: Make pin count per VMA References: https://bugs.freedesktop.org/show_bug.cgi?id=89085 Signed-off-by: Chris Wilson Reviewed-by: Daniel Vetter Cc: stable@vger.kernel.org Signed-off-by: Jani Nikula --- diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c index 7a24bd1a51f6..6377b22269ad 100644 --- a/drivers/gpu/drm/i915/i915_gem_tiling.c +++ b/drivers/gpu/drm/i915/i915_gem_tiling.c @@ -335,9 +335,10 @@ i915_gem_set_tiling(struct drm_device *dev, void *data, return -EINVAL; } + mutex_lock(&dev->struct_mutex); if (i915_gem_obj_is_pinned(obj) || obj->framebuffer_references) { - drm_gem_object_unreference_unlocked(&obj->base); - return -EBUSY; + ret = -EBUSY; + goto err; } if (args->tiling_mode == I915_TILING_NONE) { @@ -369,7 +370,6 @@ i915_gem_set_tiling(struct drm_device *dev, void *data, } } - mutex_lock(&dev->struct_mutex); if (args->tiling_mode != obj->tiling_mode || args->stride != obj->stride) { /* We need to rebind the object if its current allocation @@ -424,6 +424,7 @@ i915_gem_set_tiling(struct drm_device *dev, void *data, obj->bit_17 = NULL; } +err: drm_gem_object_unreference(&obj->base); mutex_unlock(&dev->struct_mutex);