From: Michal Luczaj Date: Wed, 21 May 2025 23:18:21 +0000 (+0200) Subject: vsock/virtio: Linger on unsent data X-Git-Tag: v6.16-rc1~132^2~25^2~4 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1c39f5dbbfd2b44602d46936fe55361205196257;p=thirdparty%2Fkernel%2Flinux.git vsock/virtio: Linger on unsent data Currently vsock's lingering effectively boils down to waiting (or timing out) until packets are consumed or dropped by the peer; be it by receiving the data, closing or shutting down the connection. To align with the semantics described in the SO_LINGER section of man socket(7) and to mimic AF_INET's behaviour more closely, change the logic of a lingering close(): instead of waiting for all data to be handled, block until data is considered sent from the vsock's transport point of view. That is until worker picks the packets for processing and decrements virtio_vsock_sock::bytes_unsent down to 0. Note that (some interpretation of) lingering was always limited to transports that called virtio_transport_wait_close() on transport release. This does not change, i.e. under Hyper-V and VMCI no lingering would be observed. The implementation does not adhere strictly to man page's interpretation of SO_LINGER: shutdown() will not trigger the lingering. This follows AF_INET. Reviewed-by: Stefano Garzarella Signed-off-by: Michal Luczaj Link: https://patch.msgid.link/20250522-vsock-linger-v6-1-2ad00b0e447e@rbox.co Signed-off-by: Paolo Abeni --- diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 6e7b727c781c8..f2f1b166731b1 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1195,12 +1195,14 @@ static void virtio_transport_wait_close(struct sock *sk, long timeout) { if (timeout) { DEFINE_WAIT_FUNC(wait, woken_wake_function); + struct vsock_sock *vsk = vsock_sk(sk); add_wait_queue(sk_sleep(sk), &wait); do { if (sk_wait_event(sk, &timeout, - sock_flag(sk, SOCK_DONE), &wait)) + virtio_transport_unsent_bytes(vsk) == 0, + &wait)) break; } while (!signal_pending(current) && timeout);