On Mon, Mar 5, 2018 at 7:50 AM, Peter Xu <pet...@redhat.com> wrote:
> TCP chardevs can be using QIO network listeners working in the
> background when in listening mode. However the network listeners are
> always running in main context. This can race with chardevs that are
> running in non-main contexts.
>
> To solve this, we need to re-setup the net listeners in
> tcp_chr_update_read_handler() with the newly cached gcontext.
>
> Signed-off-by: Peter Xu <pet...@redhat.com>
> ---
> chardev/char-socket.c | 26 ++++++++++++++++++++------
> 1 file changed, 20 insertions(+), 6 deletions(-)
>
Reviewed-by: Marc-André Lureau <marcandre.lur...@redhat.com>
> diff --git a/chardev/char-socket.c b/chardev/char-socket.c
> index 205ee377a4..5aa01e15ff 100644
> --- a/chardev/char-socket.c
> +++ b/chardev/char-socket.c
> @@ -422,8 +422,8 @@ static void tcp_chr_disconnect(Chardev *chr)
> tcp_chr_free_connection(chr);
>
> if (s->listener) {
> - qio_net_listener_set_client_func(s->listener, tcp_chr_accept,
> - chr, NULL);
> + qio_net_listener_set_client_func_full(s->listener, tcp_chr_accept,
> + chr, NULL, chr->gcontext);
> }
> update_disconnected_filename(s);
> if (emit_close) {
> @@ -559,6 +559,16 @@ static void tcp_chr_update_read_handler(Chardev *chr)
> {
> SocketChardev *s = SOCKET_CHARDEV(chr);
>
> + if (s->listener) {
> + /*
> + * It's possible that chardev context is changed in
> + * qemu_chr_be_update_read_handlers(). Reset it for QIO net
> + * listener if there is.
> + */
> + qio_net_listener_set_client_func_full(s->listener, tcp_chr_accept,
> + chr, NULL, chr->gcontext);
> + }
> +
> if (!s->connected) {
> return;
> }
> @@ -743,7 +753,8 @@ static int tcp_chr_new_client(Chardev *chr,
> QIOChannelSocket *sioc)
> qio_channel_set_delay(s->ioc, false);
> }
> if (s->listener) {
> - qio_net_listener_set_client_func(s->listener, NULL, NULL, NULL);
> + qio_net_listener_set_client_func_full(s->listener, NULL, NULL,
> + NULL, chr->gcontext);
> }
>
> if (s->tls_creds) {
> @@ -824,7 +835,8 @@ static void char_socket_finalize(Object *obj)
> tcp_chr_reconn_timer_cancel(s);
> qapi_free_SocketAddress(s->addr);
> if (s->listener) {
> - qio_net_listener_set_client_func(s->listener, NULL, NULL, NULL);
> + qio_net_listener_set_client_func_full(s->listener, NULL, NULL,
> + NULL, chr->gcontext);
> object_unref(OBJECT(s->listener));
> }
> if (s->tls_creds) {
> @@ -980,8 +992,10 @@ static void qmp_chardev_open_socket(Chardev *chr,
> return;
> }
> if (!s->ioc) {
> - qio_net_listener_set_client_func(s->listener, tcp_chr_accept,
> - chr, NULL);
> + qio_net_listener_set_client_func_full(s->listener,
> + tcp_chr_accept,
> + chr, NULL,
> + chr->gcontext);
> }
> } else if (qemu_chr_wait_connected(chr, errp) < 0) {
> goto error;
> --
> 2.14.3
>
