Documentation for the s390 DIAGNOSE 0x318 instruction handling. Signed-off-by: Collin Walling <walling@xxxxxxxxxxxxx> --- Documentation/virt/kvm/api.rst | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 426f94582b7a..056608e8f243 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -6150,3 +6150,22 @@ KVM can therefore start protected VMs. This capability governs the KVM_S390_PV_COMMAND ioctl and the KVM_MP_STATE_LOAD MP_STATE. KVM_SET_MP_STATE can fail for protected guests when the state change is invalid. + +8.24 KVM_CAP_S390_DIAG318 +------------------------- + +:Architecture: s390 + +This capability allows for information regarding the control program that may +be observed via system/firmware service events. The availability of this +capability indicates that KVM handling of the register synchronization, reset, +and VSIE shadowing of the DIAGNOSE 0x318 related information is present. + +The information associated with the instruction is an 8-byte value consisting +of a one-byte Control Program Name Code (CPNC), and a 7-byte Control Program +Version Code (CPVC). The CPNC determines what environment the control program +is running in (e.g. Linux, z/VM...), and the CPVC is used for extraneous +information specific to OS (e.g. Linux version, Linux distribution...) + +If this capability is available, then the CPNC and CPVC can be synchronized +between KVM and userspace via the sync regs mechanism (KVM_SYNC_DIAG318). -- 2.26.2
