Hi! I noticed a curious little problem with my virtualized DSL router which seems to indicate that qemu-kvm (kvm-88-1081-g561d3ed) will deliver packets to the guest over the emulated network card (tested with rtl8139 and ne2k_pci) which wouldn't appear on real hardware because they are shorter than the minimum packet size on Ethernet (64 bytes including CRC32). My current workaround is to enforce a minimum size of 64 in net.c/tap_send, but I believe this is not the correct solution - the guest now sees every packet as really 64 bytes long even when it shouldn't be. In case anyone cares how this problems manifests on my setup: PPPoE packets have a payload length field that in the case of my ISP always indicates an overall packet size of at least 64 bytes even if the incoming packet is smaller than that. The pppoe code of Linux added checks that drop all packets where the PPPoE-header-indicated length is larger than the packet length in commit 392fdb0e. On real hardware this check would never fail even with my broken ISP because Ethernet cannot transmit packets small enough to fail this check, with qemu-kvm those packets are now dropped. Short system summary, although I suspect it doesn't matter with this problem: - AMD Phenom II 905e - kvm-88-1081-g561d3ed - host kernel 2.6.26-2-amd64 (Debian lenny packaged, amd64 arch) - 32 bit Linux userspace - kvm parameters: -m 128 -k de -nographic -serial mon:stdio -echr 0x14 -hda router.img -net nic,vlan=0 -net nic,vlan=1 -net tap,vlan=0,script=ifup.sh,downscript=ifdown.sh -net tap,vlan=1,script=ifup.sh,downscript=ifdown.sh (both virtual NICs bridged to their own ethernet card on the host) - no changes with "-no-kvm" -ik -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html