Interestingly this does not appear to affect Windows guests on the same host/bridge as the ESXi guest, as Windows pads the frames before sending them out. However it does affect Linux guests on the same host/bridge from communicating with the ESXi guest itself and the guests ESXi hosts.
-- *View My LinkedIn Profile* http://uk.linkedin.com/in/bendraper00 On 20 August 2014 13:27, Ben Draper <b...@xrsa.net> wrote: > When running VMware ESXi under qemu-kvm the guest discards frames > that are too short. Short ARP Requests will be dropped, this prevents > guests on the same bridge as VMware ESXi from communicating. This patch > simply adds the padding on the network device itself. > > Signed-off-by: Ben Draper <b...@xrsa.net> > --- > hw/net/vmxnet3.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/hw/net/vmxnet3.c b/hw/net/vmxnet3.c > index 791321f..f246fa1 100644 > --- a/hw/net/vmxnet3.c > +++ b/hw/net/vmxnet3.c > @@ -34,6 +34,7 @@ > > #define PCI_DEVICE_ID_VMWARE_VMXNET3_REVISION 0x1 > #define VMXNET3_MSIX_BAR_SIZE 0x2000 > +#define MIN_BUF_SIZE 60 > > #define VMXNET3_BAR0_IDX (0) > #define VMXNET3_BAR1_IDX (1) > @@ -1871,12 +1872,21 @@ vmxnet3_receive(NetClientState *nc, const uint8_t > *buf, size_t size) > { > VMXNET3State *s = qemu_get_nic_opaque(nc); > size_t bytes_indicated; > + uint8_t min_buf[MIN_BUF_SIZE]; > > if (!vmxnet3_can_receive(nc)) { > VMW_PKPRN("Cannot receive now"); > return -1; > } > > + /* Pad to minimum Ethernet frame length */ > + if (size < sizeof(min_buf)) { > + memcpy(min_buf, buf, size); > + memset(&min_buf[size], 0, sizeof(min_buf) - size); > + buf = min_buf; > + size = sizeof(min_buf); > + } > + > if (s->peer_has_vhdr) { > vmxnet_rx_pkt_set_vhdr(s->rx_pkt, (struct virtio_net_hdr *)buf); > buf += sizeof(struct virtio_net_hdr); > -- > 1.7.10.4 > >
