On 09/22/2010 12:18 PM, Leszek Urbanski wrote:
Hi,
This is a qemu-kvm (i.e. not qemu) bug report. I've been told on IRC (#kvm)
that this bug report should go to this list anyway.
host and guest kernel: 2.6.32.22
arch: amd64
qemu-kvm: 0.12.5 and 0.13.0-rc1
How to reproduce: copy a large (few hundred MB) file to an NFS mount
(guest is the client), using qdev syntax for virtio:
-device virtio-net-pci,netdev=tap1,mac=ab:cd:ef:01:23:45 \
-netdev type=tap,id=tap1,ifname=tap1
all NFS mounts immediately stall and processes go into D state and are stuck
on nfs_wait_bit_uninterruptible. There is no further communication between
the client and the server. It occurs with UDP and TCP mounts.
That same guest, when switched to the old -net/-net syntax:
-net nic,vlan=0,model=virtio,name=eth0,macaddr=ab:cd:ef:01:23:45 \
-net tap,vlan=0,ifname=tap1
works fine. It also works fine on bare metal.
I can reproduce the problem every time within 10 minutes with qdev.
Is the guest kernel vanilla 2.6.32.22 or is it a distro kernel? If the
later, what distro?
The difference in the two invocations is that with the -device syntax,
you're getting offload features enabled.
Regards,
Anthony Liguori
