tap: Better report errors receiving from QEMU socket

If we get an error on recv() from the QEMU socket, we currently don't
print any kind of error.  Although this can happen in a non-fatal situation
such as a guest restarting, it's unusual enough that we realy should report
something for debugability.

Add an error message in this case.  Also always report when the qemu
connection closes for any reason, not just when it will cause us to exit
(--one-off).

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[sbrivio: Change error message: it's not necessarily QEMU, and mention
 that we are resetting the connection]
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
David Gibson 2024-07-26 17:20:27 +10:00 committed by Stefano Brivio
parent 77c092ee5e
commit a06db27c49

10
tap.c
View file

@ -969,10 +969,10 @@ void tap_add_packet(struct ctx *c, ssize_t l2len, char *p)
*/ */
static void tap_sock_reset(struct ctx *c) static void tap_sock_reset(struct ctx *c)
{ {
if (c->one_off) { info("Client connection closed%s", c->one_off ? ", exiting" : "");
info("Client closed connection, exiting");
if (c->one_off)
exit(EXIT_SUCCESS); exit(EXIT_SUCCESS);
}
/* Close the connected socket, wait for a new connection */ /* Close the connected socket, wait for a new connection */
epoll_ctl(c->epollfd, EPOLL_CTL_DEL, c->fd_tap, NULL); epoll_ctl(c->epollfd, EPOLL_CTL_DEL, c->fd_tap, NULL);
@ -1005,8 +1005,10 @@ redo:
n = recv(c->fd_tap, p, TAP_BUF_FILL, MSG_DONTWAIT); n = recv(c->fd_tap, p, TAP_BUF_FILL, MSG_DONTWAIT);
if (n < 0) { if (n < 0) {
if (errno != EINTR && errno != EAGAIN && errno != EWOULDBLOCK) if (errno != EINTR && errno != EAGAIN && errno != EWOULDBLOCK) {
err_perror("Receive error on guest connection, reset");
tap_sock_reset(c); tap_sock_reset(c);
}
return; return;
} }