Documentation/Platforms/S390X
QEMU s390x Guest Support
QEMU supports running s390x (aka zSystems aka mainframe) guests via the s390-virtio-ccw machine.
Supported Devices
The s390-virtio-ccw machine emulates a virtual channel subsystem. Currently, only virtio-ccw proxy devices (for most virtio device types) are supported.
As a console device, supported types are SCLP VT220-compatible (preferred), SCLP line-mode or virtio-serial console.
Links
Wikipedia page for the System 390
Installing Ubuntu Linux
Installing SUSE Linux
s390x emulator for Ubuntu