On Tue, Oct 8, 2024 at 2:52 PM Akihiko Odaki <akihiko.od...@daynix.com> wrote:
>
> ipvtap and macvtap create a file for each interface unlike tuntap, which
> creates one file shared by all interfaces. Try to open a file dedicated
> to the interface first for ipvtap and macvtap.
>
Management layers usually pass these fds via SCM_RIGHTS. Is this for
testing purposes? (Note that we can use something like -netdev
tap,fd=10 10<>/dev/tap0).
> Signed-off-by: Akihiko Odaki <akihiko.od...@daynix.com>
> ---
> net/tap-linux.c | 17 ++++++++++++++---
> 1 file changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/net/tap-linux.c b/net/tap-linux.c
> index 1226d5fda2d9..22ec2f45d2b7 100644
> --- a/net/tap-linux.c
> +++ b/net/tap-linux.c
> @@ -45,10 +45,21 @@ int tap_open(char *ifname, int ifname_size, int *vnet_hdr,
> int len = sizeof(struct virtio_net_hdr);
> unsigned int features;
>
> - fd = RETRY_ON_EINTR(open(PATH_NET_TUN, O_RDWR));
> +
> + ret = if_nametoindex(ifname);
> + if (ret) {
> + g_autofree char *file = g_strdup_printf("/dev/tap%d", ret);
> + fd = open(file, O_RDWR);
> + } else {
> + fd = -1;
> + }
> +
> if (fd < 0) {
> - error_setg_errno(errp, errno, "could not open %s", PATH_NET_TUN);
> - return -1;
> + fd = RETRY_ON_EINTR(open(PATH_NET_TUN, O_RDWR));
Any reason tuntap were tried after the macvtap/ipvtap?
> + if (fd < 0) {
> + error_setg_errno(errp, errno, "could not open %s", PATH_NET_TUN);
> + return -1;
> + }
> }
> memset(&ifr, 0, sizeof(ifr));
> ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
>
> ---
> base-commit: 31669121a01a14732f57c49400bc239cf9fd505f
> change-id: 20241008-macvtap-b152e5abb457
>
> Best regards,
> --
> Akihiko Odaki <akihiko.od...@daynix.com>
Thanks
>
