Re: [PATCH v11 16/19] KVM: s390: pv: api documentation for asynchronous destroy

Janosch Frank
2022-06-20T09:14:00Z

On 6/3/22 08:56, Claudio Imbrenda wrote:
> Add documentation for the new commands added to the KVM_S390_PV_COMMAND
> ioctl.
>
> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
> Reviewed-by: Nico Boehr <nrb@linux.ibm.com>
> ---
> Documentation/virt/kvm/api.rst | 25 ++++++++++++++++++++++---
> 1 file changed, 22 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
> index 11e00a46c610..97d35b30ce3b 100644
> --- a/Documentation/virt/kvm/api.rst
> +++ b/Documentation/virt/kvm/api.rst
> @@ -5143,11 +5143,13 @@ 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.
> + again. All registered VCPUs are converted back to non-protected
> + ones. If a previous VM had been prepared for asynchonous teardown
> + with KVM_PV_ASYNC_DISABLE_PREPARE and not actually torn down with
> + KVM_PV_ASYNC_DISABLE, 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
> @@ -5160,6 +5162,23 @@ KVM_PV_VM_VERIFY
> Verify the integrity of the unpacked image. Only if this succeeds,
> KVM is allowed to start protected VCPUs.
>
> +KVM_PV_ASYNC_DISABLE_PREPARE
> + Prepare the current protected VM for asynchronous teardown. Most
> + resources used by the current protected VM will be set aside for a

We should state that leftover UV state needs cleanup, namely secure
storage and the configuration.