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From:   David Stevens <stevensd@chromium.org>
Date:   Tue, 3 Mar 2020 11:42:22 +0900
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Subject: Re: [virtio-dev] [PATCH v2 4/4] drm/virtio: Support virtgpu exported resources
To:     Gurchetan Singh <gurchetansingh@chromium.org>
Cc:     Gerd Hoffmann <kraxel@redhat.com>, David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        "Michael S . Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>,
        Sumit Semwal <sumit.semwal@linaro.org>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        open list <linux-kernel@vger.kernel.org>,
        ML dri-devel <dri-devel@lists.freedesktop.org>,
        "open list:VIRTIO GPU DRIVER" 
        <virtualization@lists.linux-foundation.org>,
        Linux Media Mailing List <linux-media@vger.kernel.org>,
        linaro-mm-sig@lists.linaro.org, virtio-dev@lists.oasis-open.org
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> cmd_p->hdr.ctx_id =
>
> Before this completion of this hypercall, this resource can be
> considered context local, while afterward it can be considered
> "exported".

Maybe I'm misunderstanding render contexts, but exporting a resource
doesn't seem related to render contexts. The other resource management
operations (e.g. creation, attaching a backing) don't take render
contexts, and exporting a resource seems like the same sort of
operation. It's not clear to me why exporting a resource would affect
what render contexts a resource has been attached to, nor why the
render contexts a resource has been attached to would affect exporting
the resource. Also, from an implementation perspective, I don't see
any struct virtio_gpu_fpriv to get the ctx_id from.

-David