> -----Original Message----- > From: intel-gvt-dev [mailto:intel-gvt-dev-bounces@xxxxxxxxxxxxxxxxxxxxx] On > Behalf Of Joonas Lahtinen > Sent: Monday, November 6, 2017 7:24 PM > To: Zhang, Tina <tina.zhang@xxxxxxxxx>; zhenyuw@xxxxxxxxxxxxxxx; Wang, Zhi > A <zhi.a.wang@xxxxxxxxx>; daniel@xxxxxxxx; chris@xxxxxxxxxxxxxxxxxx > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx>; intel-gfx@xxxxxxxxxxxxxxxxxxxxx; > intel-gvt-dev@xxxxxxxxxxxxxxxxxxxxx > Subject: Re: [PATCH v2 1/2] drm/i915: Introduce GEM proxy > > On Wed, 2017-11-01 at 17:22 +0800, Tina Zhang wrote: > > GEM proxy is a kind of GEM, whose backing physical memory is pinned > > and produced by guest VM and is used by host as read only. With GEM > > proxy, host is able to access guest physical memory through GEM object > > interface. As GEM proxy is such a special kind of GEM, a new flag > > I915_GEM_OBJECT_IS_PROXY is introduced to ban host from changing the > > backing storage of GEM proxy. > > > > v2: > > - return -ENXIO when pin and map pages of GEM proxy to kernel space. > > (Chris) > > > > Here are the histories of this patch in "Dma-buf support for Gvt-g" > > patch-set: > > > > v14: > > - return -ENXIO when gem proxy object is banned by ioctl. > > (Chris) (Daniel) > > > > v13: > > - add comments to GEM proxy. (Chris) > > - don't ban GEM proxy in i915_gem_sw_finish_ioctl. (Chris) > > - check GEM proxy bar after finishing i915_gem_object_wait. (Chris) > > - remove GEM proxy bar in i915_gem_madvise_ioctl. > > > > v6: > > - add gem proxy barrier in the following ioctls. (Chris) > > i915_gem_set_caching_ioctl > > i915_gem_set_domain_ioctl > > i915_gem_sw_finish_ioctl > > i915_gem_set_tiling_ioctl > > i915_gem_madvise_ioctl > > > > Signed-off-by: Tina Zhang <tina.zhang@xxxxxxxxx> > > Reviewed-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> > > Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > Cc: Daniel Vetter <daniel.vetter@xxxxxxxx> > > <SNIP> > > > @@ -1649,6 +1659,10 @@ i915_gem_sw_finish_ioctl(struct drm_device > *dev, void *data, > > if (!obj) > > return -ENOENT; > > > > + /* Proxy objects are barred from CPU access, so there is no > > + * need to ban sw_finish as it is a nop. > > + */ > > + > > /* Pinned buffers may be scanout, so flush the cache */ > > i915_gem_object_flush_if_display(obj); > > i915_gem_object_put(obj); > > @@ -2614,7 +2628,8 @@ void *i915_gem_object_pin_map(struct > drm_i915_gem_object *obj, > > void *ptr; > > int ret; > > > > - GEM_BUG_ON(!i915_gem_object_has_struct_page(obj)); > > + if (unlikely(!i915_gem_object_has_struct_page(obj))) > > + return ERR_PTR(-ENODEV); > > You should have marked this change in the changelog and then marked the > Reviewed-by tags to be valid only to the previous version of this patch. > > It's not a fair game to claim a patch to be "Reviewed-by" at the current version, > when you've made changes that were not agreed upon. I thought we were agreed on this :) > > So that's some meta-review. Back to the actual review; > > Which codepath was hitting the GEM_BUG_ON? Wondering if it would be > cleaner to avoid the call to this function on that single codepath. Here is the previously comments: https://lists.freedesktop.org/archives/intel-gvt-dev/2017-October/002278.html Thanks. BR, Tina > > Regards, Joonas > -- > Joonas Lahtinen > Open Source Technology Center > Intel Corporation > _______________________________________________ > intel-gvt-dev mailing list > intel-gvt-dev@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/intel-gvt-dev _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
