On Mon, Nov 22, 2021, Paolo Bonzini wrote:
> Allow intra-host migration of a mirror VM; the destination VM will be
> a mirror of the same ASID as the source.
>
> Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration")
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
> arch/x86/kvm/svm/sev.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
> index dc974c1728b6..c1eb1c83401d 100644
> --- a/arch/x86/kvm/svm/sev.c
> +++ b/arch/x86/kvm/svm/sev.c
> @@ -1616,11 +1616,13 @@ static void sev_migrate_from(struct kvm_sev_info *dst,
> dst->asid = src->asid;
> dst->handle = src->handle;
> dst->pages_locked = src->pages_locked;
> + dst->enc_context_owner = src->enc_context_owner;
>
> src->asid = 0;
> src->active = false;
> src->handle = 0;
> src->pages_locked = 0;
> + src->enc_context_owner = NULL;
Ah, since this is effectively transferring the kvm_put_kvm() "owner", I definitely
think a refcount on the number of mirrors is the way to go.
Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>
