Hello, with the current qemu-kvm release candidate our diskless linux guests cannot use their NFS root filesystem anymore. /usr/local/bin/qemu-system-x86_64 -m 4096 -smp 1 -boot n -net nic,macaddr=00:50:56:24:0b:57,model=rtl8139 -net tap,ifname=vm01,script=no,downscript=no This boots via the pxe-rtl8139.bin Boot ROM and starts a locally-developed diskless boot environment. (Unfortunately I'm not able to describe this in detail, and I didn't manage to reproduce this in an easier environment.) When this boot environment tries to mount the new root filesystem via NFS, these message appear, waiting severeal seconds between each line: nfs: server 172.31.11.10 not responding, still trying nfs: server 172.31.11.10 OK This continues until I kill the qemu process. During this problem the guests IP address can be pinged. The problem disappears with each of these: - qemu-kvm-0.10.6 - model=virtio or model=e1000 These changes didn't help: - -no-kvm-irqchip - -no-kvm-pit - -no-kvm - qemu-system-x86_64 instantly coredumps - qemu-kvm-0.11.0-rc1 My environment: - Host - Linux 2.6.31-rc9 x86_64 - kvm kernel components from this kernel - Dual-Socket AMD Opteron 2347 HE - Guest - Linux 2.6.25.9 i686 I tried to watch this with tcpdump. Before the line "nfs: server 172.31.11.10 OK" it looks like this: 13:45:28.665935 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.665940 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666162 IP 172.31.11.10.948098278 > 172.31.10.11.2049: 112 read [|nfs] 13:45:28.666259 IP 172.31.11.10.964875494 > 172.31.10.11.2049: 112 read [|nfs] 13:45:28.666345 IP 172.31.10.11.2049 > 172.31.11.10.948098278: reply ok 1472 read 13:45:28.666403 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666408 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666412 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666416 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666421 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666464 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666469 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666476 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666482 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666487 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666526 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666532 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666538 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666543 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666549 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666587 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666594 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666599 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666605 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666613 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666622 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666628 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666929 IP 172.31.10.11.2049 > 172.31.11.10.964875494: reply ok 1472 read 13:45:28.666935 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666940 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666944 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666949 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666991 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.666996 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667002 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667008 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667014 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667052 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667058 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667064 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667069 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667075 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667114 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667121 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667128 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667134 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667140 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667160 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667168 IP 172.31.10.11 > 172.31.11.10: udp 13:45:28.667174 IP 172.31.10.11 > 172.31.11.10: udp and after this line this appears: 13:45:41.261362 IP 172.31.11.10 > 172.31.10.11: ICMP ip reassembly time exceeded, length 556 13:45:41.682275 IP 172.31.11.10 > 172.31.10.11: ICMP ip reassembly time exceeded, length 556 13:45:42.091219 IP 172.31.11.10 > 172.31.10.11: ICMP ip reassembly time exceeded, length 556 13:45:42.942096 IP 172.31.11.10 > 172.31.10.11: ICMP ip reassembly time exceeded, length 556 13:45:46.260603 arp who-has 172.31.10.11 tell 172.31.11.10 13:45:46.260756 arp reply 172.31.10.11 is-at 00:c0:9f:ca:9a:78 13:45:56.507139 IP 172.31.11.10 > 172.31.10.11: ICMP ip reassembly time exceeded, length 556 13:45:57.207030 IP 172.31.11.10 > 172.31.10.11: ICMP ip reassembly time exceeded, length 556 13:45:58.688814 IP 172.31.11.10 > 172.31.10.11: ICMP ip reassembly time exceeded, length 556 Thats all informatiion I extracted for now. If needed I would try to provide additional information or run some tests. Thanks, Sven -- 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