On Tue, 07/07 11:13, Michael S. Tsirkin wrote:
> On Tue, Jul 07, 2015 at 09:21:07AM +0800, Fam Zheng wrote:
> > Since commit 6e99c63 "net/socket: Drop net_socket_can_send" and friends,
> > net queues need to be explicitly flushed after qemu_can_send_packet()
> > returns false, because the netdev side will disable the polling of fd.
> >
> > This fixes the case of "cont" after "stop" (or migration).
> >
> > Signed-off-by: Fam Zheng <f...@redhat.com>
>
> Note virtio has its own handler which must be used to
> flush packets - this one might run too early or too late.
Which handler do you mean? I don't think virtio-net handles resume now. (If it
does, we probably should drop it together with this change, since it's needed
by as all NICs.)
Fam
>
> > ---
> >
> > v2: Unify with VM stop handler. (Stefan)
> > ---
> > net/net.c | 19 ++++++++++++-------
> > 1 file changed, 12 insertions(+), 7 deletions(-)
> >
> > diff --git a/net/net.c b/net/net.c
> > index 6ff7fec..28a5597 100644
> > --- a/net/net.c
> > +++ b/net/net.c
> > @@ -1257,14 +1257,19 @@ void qmp_set_link(const char *name, bool up, Error
> > **errp)
> > static void net_vm_change_state_handler(void *opaque, int running,
> > RunState state)
> > {
> > - /* Complete all queued packets, to guarantee we don't modify
> > - * state later when VM is not running.
> > - */
> > - if (!running) {
> > - NetClientState *nc;
> > - NetClientState *tmp;
> > + NetClientState *nc;
> > + NetClientState *tmp;
> >
> > - QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
> > + QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
> > + if (running) {
> > + /* Flush queued packets and wake up backends. */
> > + if (nc->peer && qemu_can_send_packet(nc)) {
> > + qemu_flush_queued_packets(nc->peer);
> > + }
> > + } else {
> > + /* Complete all queued packets, to guarantee we don't modify
> > + * state later when VM is not running.
> > + */
> > qemu_flush_or_purge_queued_packets(nc, true);
> > }
> > }
> > --
> > 2.4.3
