Re: [Qemu-devel] [PATCH 23/24] vhost-user: wait until link is up

[Michael S. Tsirkin]

On Tue, Jun 21, 2016 at 12:02:51PM +0200, address@hidden wrote:
> From: Marc-André Lureau <address@hidden>
> 
> The chardev waits for an initial connection before starting qemu,
> vhost-user wants the backend negotiation to be completed. vhost-user is
> started in the net_vhost_user_event callback, which is synchronously
> called after the socket is connected.
> 
> Signed-off-by: Marc-André Lureau <address@hidden>
> ---
>  net/vhost-user.c | 10 +++++++++-
>  1 file changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/net/vhost-user.c b/net/vhost-user.c
> index 95ed2d2..bb4a253 100644
> --- a/net/vhost-user.c
> +++ b/net/vhost-user.c
> @@ -248,7 +248,15 @@ static int net_vhost_user_init(NetClientState *peer, 
> const char *device,
>          s->chr = chr;
>      }
>  
> -    qemu_chr_add_handlers(chr, NULL, NULL, net_vhost_user_event, nc[0].name);
> +    do {
> +        Error *err = NULL;
> +        if (qemu_chr_wait_connected(chr, &err) < 0) {
> +            error_report_err(err);
> +            return -1;
> +        }
> +        qemu_chr_add_handlers(chr, NULL, NULL,
> +                              net_vhost_user_event, nc[0].name);
> +    } while (nc->link_down);
>  
>      assert(s->vhost_net != NULL);


I don't get why this makes sense.
Why should vhost user poke at link down at all?

> -- 
> 2.7.4