Let's say I have a vm, vm1, which has a lv as its hard drive: <disk type='file' device='disk'> <driver name='qemu' type='raw' cache='none' io='native'/> <source file='/dev/mapper/kvmtest_vm1_rootvg'/> <target dev='vda' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </disk> I could add pickles as a second drive as follows: <disk type='file' device='disk'> <driver name='qemu' type='raw' cache='none' io='native'/> <source file='/dev/mapper/kvmtest_pickles'/> <target dev='vdb' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/> </disk> but I am trying to understand the pci address entry. Must drive be on a different slot?