Hi ,

Trying to attach a disk to existing VM using virsh attach-device - 


XML 

<disk type='file' device='disk'>
      <driver name='qemu' type='qcow2' cache='none' io='native'/>
      <source file='/var/lib/libvirt/images/guest.qcow2'/>
      <target dev='vdc' bus='virtio'/>
</disk>


After executing the command I am getting - 

[root@cent7 ~]# virsh attach-device lib-virt-man-001 newDisk.xml
error: Failed to attach device from newDisk.xml
error: internal error: unable to execute QEMU command 'device_add': Bus 'pci.0' does not support hotplugging.


[root@cent7 ~]# virsh version
Compiled against library: libvirt 1.2.17
Using library: libvirt 1.2.17
Using API: QEMU 1.2.17
Running hypervisor: QEMU 1.5.3



While searching on this issue found that some have suggested to install following - 
modprobe acpiphp
modprobe pci_hotplug
 I am not sure if this is QEMU issue or libvirt issue. 
Any help in this would be appreciated.
Thanks,
Keyur Bhalerao