On Tue, Dec 15, 2015 at 02:41:47PM +0000, Dave Gordon wrote: > On 14/12/15 05:46, ankitprasad.r.sharma@xxxxxxxxx wrote: > >From: Ankitprasad Sharma <ankitprasad.r.sharma@xxxxxxxxx> > > > >Using stolen backed objects as a batchbuffer may result into a kernel > >panic during relocation. Added a check to prevent the panic and fail > >the execbuffer call. It is not recommended to use stolen object as > >a batchbuffer. > > > >Signed-off-by: Ankitprasad Sharma <ankitprasad.r.sharma@xxxxxxxxx> > >--- > > drivers/gpu/drm/i915/i915_gem_execbuffer.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > >diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c > >index 48ec484..d342f10 100644 > >--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c > >+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c > >@@ -462,7 +462,9 @@ i915_gem_execbuffer_relocate_entry(struct drm_i915_gem_object *obj, > > if (obj->active && pagefault_disabled()) > > return -EFAULT; > > > >- if (use_cpu_reloc(obj)) > >+ if (obj->stolen) > >+ ret = -EINVAL; > > I'd rather reject ALL "weird" gem objects at the first opportunity, > so that none of the execbuffer code has to worry about stolen, phys, > dmabuf, etc ... > > if (obj->ops != &i915_gem_object_ops)) > ret = -EINVAL; /* No exotica please */ No. All GEM objects are supposed to be first-class so that they are interchangeable through all aspects of the API (that becomes even more important with dma-buf interoperation). We have had to relax that for a couple of special categories (basically CPU mmapping) for certain clases that are not struct file backed. Though in principle, a gemfs would work just fine. The only restrictions we should ideally impose are those determined by hardware. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx