Re: [Qemu-devel] virtio-gpu: cursor update not in sync with resource update

[Dave Airlie]

On 15 September 2015 at 01:17, Marc-André Lureau
<address@hidden> wrote:
> Hi
>
> On Mon, Sep 14, 2015 at 4:06 PM, Gerd Hoffmann <address@hidden> wrote:
>> The guest can upload different cursors and then switch between them
>> without re-uploading and therefore without ctrl queue updates.  Thats
>> why they have an id in the first place ...
>
> Ok, but the cursor id is reused most of the time. So there are at
> least two things to fix: use different cursor ids for different cursor
> data (with some cache management probably), fix kernel to only upload
> new resource id and wait for data to be transfered. Is that correct?

Currently the kernel driver does this:

        ret = virtio_gpu_cmd_transfer_to_host_2d(vgdev, qobj->hw_res_handle, 0,
                                                 cpu_to_le32(64),
                                                 cpu_to_le32(64),
                                                 0, 0, &fence);
        if (!ret) {
                reservation_object_add_excl_fence(qobj->tbo.resv,
                                                  &fence->f);
                virtio_gpu_object_wait(qobj, false);
        }

before moving the cursor, shouldn't that suffice?

Do we fail the transfer sometimes?

Dave.