On 6/6/22 4:33 PM, Matthew Rosato wrote:
Enable interpretive execution of zPCI instructions + adapter interruption forwarding for s390x KVM vfio-pci. This is done by triggering a routine when the VFIO group is associated with the KVM guest, transmitting to firmware a special token (GISA designation) to enable that specific guest for interpretive execution on that zPCI device. Load/store interpreation enablement is then controlled by userspace (based upon whether or not a SHM bit is placed in the virtual function handle). Adapter Event Notification interpretation is controlled from userspace via a new KVM ioctl. By allowing intepretation of zPCI instructions and firmware delivery of interrupts to guests, we can reduce the frequency of guest SIE exits for zPCI. From the perspective of guest configuration, you passthrough zPCI devices in the same manner as before, with intepretation support being used by default if available in kernel+qemu. Will follow up with a link the most recent QEMU series.
Latest QEMU series: https://lore.kernel.org/kvm/20220606203614.110928-1-mjrosato@xxxxxxxxxxxxx/
