From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52517) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1erJqI-0008AL-01 for qemu-devel@nongnu.org; Thu, 01 Mar 2018 03:45:35 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1erJqH-0007Dq-3D for qemu-devel@nongnu.org; Thu, 01 Mar 2018 03:45:34 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:42110 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1erJqG-0007DS-Rk for qemu-devel@nongnu.org; Thu, 01 Mar 2018 03:45:33 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 29E9DFB650 for ; Thu, 1 Mar 2018 08:45:32 +0000 (UTC) From: Peter Xu Date: Thu, 1 Mar 2018 16:44:30 +0800 Message-Id: <20180301084438.13594-8-peterx@redhat.com> In-Reply-To: <20180301084438.13594-1-peterx@redhat.com> References: <20180301084438.13594-1-peterx@redhat.com> Subject: [Qemu-devel] [PATCH v2 07/15] qio/chardev: update net listener gcontext List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Paolo Bonzini , "Daniel P . Berrange" , Juan Quintela , peterx@redhat.com, =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Markus Armbruster , Stefan Hajnoczi , "Dr . David Alan Gilbert" 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. Since at it, generalize a tcp_chr_net_listener_setup() helper function and clean up the old code a bit. Signed-off-by: Peter Xu --- chardev/char-socket.c | 32 ++++++++++++++++++++++++++------ 1 file changed, 26 insertions(+), 6 deletions(-) diff --git a/chardev/char-socket.c b/chardev/char-socket.c index 43a2cc2c1c..5cd20cc932 100644 --- a/chardev/char-socket.c +++ b/chardev/char-socket.c @@ -410,6 +410,19 @@ static void update_disconnected_filename(SocketChardev *s) s->is_listen, s->is_telnet); } +/* Set enable=true to start net listeners, false to stop them. */ +static void tcp_chr_net_listener_setup(SocketChardev *s, bool enable) +{ + Chardev *chr = CHARDEV(s); + + /* Net listeners' context will follow the Chardev's. */ + qio_net_listener_set_client_func_full(s->listener, + enable ? tcp_chr_accept : NULL, + enable ? chr : NULL, + NULL, + chr->gcontext); +} + /* NB may be called even if tcp_chr_connect has not been * reached, due to TLS or telnet initialization failure, * so can *not* assume s->connected == true @@ -422,8 +435,7 @@ 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); + tcp_chr_net_listener_setup(s, true); } update_disconnected_filename(s); if (emit_close) { @@ -559,6 +571,15 @@ 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. + */ + tcp_chr_net_listener_setup(s, true); + } + if (!s->connected) { return; } @@ -742,7 +763,7 @@ 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); + tcp_chr_net_listener_setup(s, false); } if (s->tls_creds) { @@ -823,7 +844,7 @@ 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); + tcp_chr_net_listener_setup(s, false); object_unref(OBJECT(s->listener)); } if (s->tls_creds) { @@ -979,8 +1000,7 @@ 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); + tcp_chr_net_listener_setup(s, true); } } else if (qemu_chr_wait_connected(chr, errp) < 0) { goto error; -- 2.14.3