[libvirt-users] error: Failed to start domain

On a gentoo server with libvirt-1.1.3 I get problems with starting VMs. When I do: # virsh start vm180 error: Failed to start domain vm180 error: Input/output error This happens with 1.1.3 and 1.1.4 (I rebuilt the packages and restarted the libvirtd.service). # journalctl -f -u libvirtd.service shows: Dec 03 17:32:56 jupiter libvirtd[24020]: Input/output error Dec 03 17:33:47 jupiter libvirtd[24020]: Input/output error The log for the specific VM shows: 2013-12-03 16:33:47.004+0000: starting up LC_ALL=C PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin QEMU_AUDIO_DRV=none /usr/bin/qemu-kvm -name vm180 -S -machine pc-i440fx-1.5,accel=kvm,usb=off -cpu Opteron_G5,+bmi1,+perfctr_nb,+perfctr_core,+topoext,+nodeid_msr,+tce,+lwp,+wdt,+skinit,+ibs,+osvw,+cr8legacy,+extapic,+cmp_legacy,+fxsr_opt,+mmxext,+osxsave,+monitor,+ht,+vme -m 3954 -realtime mlock=off -smp 4,sockets=4,cores=1,threads=1 -uuid 646f757f-2ab7-4fdf-2140-a79396200c6f -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/vm180.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=localtime,clock=vm,driftfix=slew -no-kvm-pit-reinjection -no-hpet -no-shutdown -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -drive file=/dev/VG01/vm180_disk0,if=none,id=drive-virtio-disk0,format=raw,cache=none,aio=threads -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x7,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -drive file=/mnt/tests/grml64-full_2013.02.iso,if=none,id=drive-ide0-1-0,readonly=on,format=raw -device ide-cd,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0 -netdev tap,fd=27,id=hostnet0,vhost=on,vhostfd=28 -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:8d:3b:af,bus=pci.0,addr=0x3 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -vnc 127.0.0.1:5 -vga cirrus -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x6 2013-12-03 16:33:47.013+0000: shutting down libvirt: error : libvirtd quit during handshake: Input/output error What can I do about this issue? Thanks for any pointers, Stefan