On Fri, Dec 23, 2016 at 07:14:21AM +0000, Jianfeng Tan wrote:
> In driver probe phase, we obtain device information; and then virtio
> driver will initialize device and stores info, like negotiated
> features, in vhost_user layer; finally, vhost_user gets DRIVER_OK
> notification from virtio driver, and then sync with backend device.
>
> Previously, DRIVER_OK could be sent twice: 1. when ether layer invokes
> eth_device_init to initialize device; 2. when user configures it with
> different configuration from that of previous.
Yes, but that's wrong. Now only 1) will be taken.
> Since we can only depend on DRIVER_OK notification to sync with backend
> device, we postpone it to virtio_dev_start when everything is settled.
I don't quite understand what you were going to fix here; you don't
state it in the commit log after all. Normally, when everything is
negotiated (when DRIVER_OK is set), we should not set it again, unless
a reset has been happened.
If you look at QEMU, qemu will simply ignore it once vhost has already
started.
--yliu
