PCI devices on s390x
PCI devices on s390x work differently than on other architectures and need to be configured in a slightly different way.
Every PCI device is linked with an additional
zpci device will be autogenerated if not specified, it is
recommended to specify it explicitly so that you can pass s390-specific
For example, in order to pass a PCI device
0000:00:00.0 through to the
guest, you would specify:
qemu-system-s390x ... \ -device zpci,uid=1,fid=0,target=hostdev0,id=zpci1 \ -device vfio-pci,host=0000:00:00.0,id=hostdev0
Here, the zpci device is joined with the PCI device via the
Note that we don’t set bus, slot or function here for the guest as is common in other PCI implementations. Topology information is not available on s390x, and the guest will not see any of the bus, slot or function information specified on the command line.
fid determine how the device is presented to the guest
In case of Linux,
uid will be used in the
domain part of the PCI
fid identifies the physical slot, i.e.:
qemu-system-s390x ... \ -device zpci,uid=7,fid=8,target=hostdev0,id=zpci1 \ ...
will be presented in the guest as:
# lspci -v 0007:00:00.0 ... Physical Slot: 00000008 ...