The network stream backend uses the async QIO socket APIs for listening
and connecting sockets. It does not check the task object completion
status, however, instead just looking at whether the socket FD is -1
or not.
By checking the task completion, we can set a useful error message for
users instead of the non-actionable "connection error" string.
eg so users will see:
(qemu) info network
net: index=0,type=stream,error: Failed to connect to '/foo.unix': No such file or directory
Signed-off-by: "Daniel P. Berrangé" <berrange@redhat.com>
Message-ID: <20240104162942.211458-6-berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
When running 'info network', if the stream backend is still in
the process of connecting, or waiting for an incoming connection,
no information is displayed.
There is also no way to distinguish whether the server is still
in the process of setting up the listener socket, or whether it
is ready to accept incoming client connections.
This leads to a race condition in the netdev-socket qtest which
launches a server process followed by a client process. Under
high load conditions it is possible for the client to attempt
to connect before the server is accepting clients. For the
scenarios which do not set the 'reconnect' option, this opens
up a race which can lead to the test scenario failing to reach
the expected state.
Now that 'info network' can distinguish between initialization
phase and the listening phase, the netdev-socket qtest will
correctly synchronize, such that the client QEMU is not spawned
until the server is ready.
This should solve the non-deterministic failures seen with the
netdev-socket qtest.
Signed-off-by: "Daniel P. Berrangé" <berrange@redhat.com>
Message-ID: <20240104162942.211458-5-berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
In stream mode, if the server shuts down there is currently
no way to reconnect the client to a new server without removing
the NIC device and the netdev backend (or to reboot).
This patch introduces a reconnect option that specifies a delay
to try to reconnect with the same parameters.
Add a new test in qtest to test the reconnect option and the
connect/disconnect events.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
With the G_GNUC_PRINTF function attribute the compiler detects
two potential insecure format strings:
../../../net/stream.c:248:31: warning: format string is not a string literal (potentially insecure) [-Wformat-security]
qemu_set_info_str(&s->nc, uri);
^~~
../../../net/stream.c:322:31: warning: format string is not a string literal (potentially insecure) [-Wformat-security]
qemu_set_info_str(&s->nc, uri);
^~~
There are also two other warnings:
../../../net/socket.c:182:35: warning: zero-length gnu_printf format string [-Wformat-zero-length]
182 | qemu_set_info_str(&s->nc, "");
| ^~
../../../net/stream.c:170:35: warning: zero-length gnu_printf format string [-Wformat-zero-length]
170 | qemu_set_info_str(&s->nc, "");
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20221126152507.283271-7-sw@weilnetz.de>
The netdev reports NETDEV_STREAM_CONNECTED event when the backend
is connected, and NETDEV_STREAM_DISCONNECTED when it is disconnected.
The NETDEV_STREAM_CONNECTED event includes the destination address.
This allows a system manager like libvirt to detect when the server
fails.
For instance with passt:
{ 'execute': 'qmp_capabilities' }
{ "return": { } }
{ "timestamp": { "seconds": 1666341395, "microseconds": 505347 },
"event": "NETDEV_STREAM_CONNECTED",
"data": { "netdev-id": "netdev0",
"addr": { "path": "/tmp/passt_1.socket", "type": "unix" } } }
[killing passt here]
{ "timestamp": { "seconds": 1666341430, "microseconds": 968694 },
"event": "NETDEV_STREAM_DISCONNECTED",
"data": { "netdev-id": "netdev0" } }
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Use QIOChannel, QIOChannelSocket and QIONetListener.
This allows net/stream to use all the available parameters provided by
SocketAddress.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com> (QAPI schema)
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Other errors are treated as failure by net_stream_client_init(),
but if connect() returns EINVAL, we'll fail silently. Remove the
related exception.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
[lvivier: applied to net/stream.c]
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Copied from socket netdev file and modified to use SocketAddress
to be able to introduce new features like unix socket.
"udp" and "mcast" are squashed into dgram netdev, multicast is detected
according to the IP address type.
"listen" and "connect" modes are managed by stream netdev. An optional
parameter "server" defines the mode (off by default)
The two new types need to be parsed the modern way with -netdev, because
with the traditional way, the "type" field of netdev structure collides with
the "type" field of SocketAddress and prevents the correct evaluation of the
command line option. Moreover the traditional way doesn't allow to use
the same type (SocketAddress) several times with the -netdev option
(needed to specify "local" and "remote" addresses).
The previous commit paved the way for parsing the modern way, but
omitted one detail: how to pick modern vs. traditional, in
netdev_is_modern().
We want to pick based on the value of parameter "type". But how to
extract it from the option argument?
Parsing the option argument, either the modern or the traditional way,
extracts it for us, but only if parsing succeeds.
If parsing fails, there is no good option. No matter which parser we
pick, it'll be the wrong one for some arguments, and the error
reporting will be confusing.
Fortunately, the traditional parser accepts *anything* when called in
a certain way. This maximizes our chance to extract the value of
"type", and in turn minimizes the risk of confusing error reporting.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Daniel P. Berrangé
Laurent Vivier
Stefan Weil via
Stefano Brivio