Add documentation for the new commands added to the KVM_S390_PV_COMMAND
ioctl.
Signed-off-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
Reviewed-by: Nico Boehr <nrb@xxxxxxxxxxxxx>
---
Documentation/virt/kvm/api.rst | 30 ++++++++++++++++++++++++++++--
1 file changed, 28 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index 9788b19f9ff7..5bd151b601b4 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -5163,8 +5163,11 @@ KVM_PV_ENABLE
KVM_PV_DISABLE
Deregister the VM from the Ultravisor and reclaim the memory that
had been donated to the Ultravisor, making it usable by the kernel
- again. All registered VCPUs are converted back to non-protected
- ones.
+ again. All registered VCPUs are converted back to non-protected
+ ones. If a previous VM had been set aside for asynchonous teardown
+ with KVM_PV_ASYNC_CLEANUP_PREPARE and not actually torn down with
+ KVM_PV_ASYNC_CLEANUP_PERFORM, it will be torn down in this call
+ together with the current VM.
KVM_PV_VM_SET_SEC_PARMS
Pass the image header from VM memory to the Ultravisor in
@@ -5287,6 +5290,29 @@ KVM_PV_DUMP
authentication tag all of which are needed to decrypt the dump at a
later time.
+KVM_PV_ASYNC_CLEANUP_PREPARE
+ Prepare the current protected VM for asynchronous teardown. Most
+ resources used by the current protected VM will be set aside for a
+ subsequent asynchronous teardown. The current protected VM will then
+ resume execution immediately as non-protected. There can be at most
+ one protected VM set aside at any time. If a protected VM had
+ already been set aside without starting the asynchronous teardown
+ process, this call will fail. In that case, the userspace process
+ should issue a normal KVM_PV_DISABLE. The resources set aside with
+ this call will need to be cleaned up with a subsequent call to
+ KVM_PV_ASYNC_CLEANUP_PERFORM or KVM_PV_DISABLE, otherwise they will
+ be cleaned up when KVM terminates.
+
+KVM_PV_ASYNC_CLEANUP_PERFORM
+ Tear down the protected VM previously set aside with
+ KVM_PV_ASYNC_CLEANUP_PREPARE. The resources that had been set aside
+ will be freed during the execution of this command. This PV command
+ should ideally be issued by userspace from a separate thread. If a
+ fatal signal is received (or the process terminates naturally), the
+ command will terminate immediately without completing, and the normal
+ KVM shutdown procedure will take care of cleaning up all remaining
+ protected VMs.
+
4.126 KVM_X86_SET_MSR_FILTER
----------------------------
--
2.37.1
