From d9459922a15ce7a20a85b38a976494ac7f445732 Mon Sep 17 00:00:00 2001 From: Claudio Imbrenda Date: Fri, 11 Nov 2022 18:06:28 +0100 Subject: [PATCH] KVM: s390: pv: api documentation for asynchronous destroy Add documentation for the new commands added to the KVM_S390_PV_COMMAND ioctl. Signed-off-by: Claudio Imbrenda Reviewed-by: Nico Boehr Reviewed-by: Steffen Eiden Reviewed-by: Janosch Frank Link: https://lore.kernel.org/r/20221111170632.77622-3-imbrenda@linux.ibm.com Message-Id: <20221111170632.77622-3-imbrenda@linux.ibm.com> Signed-off-by: Janosch Frank --- Documentation/virt/kvm/api.rst | 41 +++++++++++++++++++++++++++++++++++++---- 1 file changed, 37 insertions(+), 4 deletions(-) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index eee9f857a986..9175d41e8081 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -5163,10 +5163,13 @@ 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. + 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. If a + previous protected VM had been prepared for asynchonous teardown with + KVM_PV_ASYNC_CLEANUP_PREPARE and not subsequently torn down with + KVM_PV_ASYNC_CLEANUP_PERFORM, it will be torn down in this call + together with the current protected VM. KVM_PV_VM_SET_SEC_PARMS Pass the image header from VM memory to the Ultravisor in @@ -5289,6 +5292,36 @@ KVM_PV_DUMP authentication tag all of which are needed to decrypt the dump at a later time. +KVM_PV_ASYNC_CLEANUP_PREPARE + :Capability: KVM_CAP_S390_PROTECTED_ASYNC_DISABLE + + 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 prepared for asynchronous teardown at any time. If + a protected VM had already been prepared for teardown without + subsequently calling KVM_PV_ASYNC_CLEANUP_PERFORM, 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_PREPARE can be called again as soon + as cleanup starts, i.e. before KVM_PV_ASYNC_CLEANUP_PERFORM finishes. + +KVM_PV_ASYNC_CLEANUP_PERFORM + :Capability: KVM_CAP_S390_PROTECTED_ASYNC_DISABLE + + Tear down the protected VM previously prepared for teardown 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, including the ones whose teardown was interrupted by + process termination. + 4.126 KVM_XEN_HVM_SET_ATTR -------------------------- -- 2.11.0