Re: [Intel-gfx] [PATCH v2] drm/i915: Restrict pagefault disabling to just around copy_from_user()

2016-10-18 Thread Tvrtko Ursulin
On 18/10/2016 10:07, Chris Wilson wrote: When handling execbuf relocations, we play a delicate dance with pagefault. We first try to access the user pages underneath our struct_mutex. However, if those pages were inside a GEM object, we may trigger a pagefault and deadlock as i915_gem_fault()

[Intel-gfx] [PATCH v2] drm/i915: Restrict pagefault disabling to just around copy_from_user()

2016-10-18 Thread Chris Wilson
When handling execbuf relocations, we play a delicate dance with pagefault. We first try to access the user pages underneath our struct_mutex. However, if those pages were inside a GEM object, we may trigger a pagefault and deadlock as i915_gem_fault() tries to recursively acquire struct_mutex.