net/tap-bsd.c was assuming IFF_VNET_HDR was always available, which I think isn't true on any BSD.
Signed-off-by: Juergen Lock <n...@jelal.kn-bremen.de> --- a/net/tap-bsd.c +++ b/net/tap-bsd.c @@ -87,6 +87,17 @@ int tap_open(char *ifname, int ifname_si dev = devname(s.st_rdev, S_IFCHR); pstrcpy(ifname, ifname_size, dev); + if (*vnet_hdr) { + /* BSD doesn't have IFF_VNET_HDR */ + *vnet_hdr = 0; + + if (vnet_hdr_required && !*vnet_hdr) { + qemu_error("vnet_hdr=1 requested, but no kernel " + "support for IFF_VNET_HDR available"); + close(fd); + return -1; + } + } fcntl(fd, F_SETFL, O_NONBLOCK); return fd; }