Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/vapier...

[cascardo/linux.git] / drivers / gpu / drm / i915 / i915_gem_execbuffer.c

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 7ff7f93..20a4cc5 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -367,6 +367,10 @@ i915_gem_execbuffer_relocate_entry(struct drm_i915_gem_object *obj,
                uint32_t __iomem *reloc_entry;
                void __iomem *reloc_page;
 
+               /* We can't wait for rendering with pagefaults disabled */
+               if (obj->active && in_atomic())
+                       return -EFAULT;
+
                ret = i915_gem_object_set_to_gtt_domain(obj, 1);
                if (ret)
                        return ret;
@@ -440,15 +444,24 @@ i915_gem_execbuffer_relocate(struct drm_device *dev,
                             struct list_head *objects)
 {
        struct drm_i915_gem_object *obj;
-       int ret;
-
+       int ret = 0;
+
+       /* This is the fast path and we cannot handle a pagefault whilst
+        * holding the struct mutex lest the user pass in the relocations
+        * contained within a mmaped bo. For in such a case we, the page
+        * fault handler would call i915_gem_fault() and we would try to
+        * acquire the struct mutex again. Obviously this is bad and so
+        * lockdep complains vehemently.
+        */
+       pagefault_disable();
        list_for_each_entry(obj, objects, exec_list) {
                ret = i915_gem_execbuffer_relocate_object(obj, eb);
                if (ret)
-                       return ret;
+                       break;
        }
+       pagefault_enable();
 
-       return 0;
+       return ret;
 }
 
 static int