On 7/14/21 11:01 AM, Peter Gonda wrote:
For SEV to work with intra host migration, contents of the SEV info struct such as the ASID (used to index the encryption key in the AMD SP) and the list of memory regions need to be transferred to the target VM. This change adds commands for sending and receiving the sev info. To avoid exposing this internal state to userspace and prevent other processes from importing state they shouldn't have access to, the send returns a token to userspace that is handed off to the target VM. The target passes in this token to receive the sent state. The token is only valid for one-time use. Functionality on the source becomes limited after send has been performed. If the source is destroyed before the target has received, the token becomes invalid. The target is expected to be initialized (sev_guest_init), but not launched state (sev_launch_start) when performing receive. Once the target has received, it will be in a launched state and will not need to perform the typical SEV launch commands. Co-developed-by: Lars Bull <larsbull@xxxxxxxxxx> Signed-off-by: Lars Bull <larsbull@xxxxxxxxxx> Signed-off-by: Peter Gonda <pgonda@xxxxxxxxxx> Reviewed-by: Marc Orr <marcorr@xxxxxxxxxx> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> Cc: Sean Christopherson <seanjc@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Dr. David Alan Gilbert <dgilbert@xxxxxxxxxx> Cc: Brijesh Singh <brijesh.singh@xxxxxxx> Cc: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> Cc: Wanpeng Li <wanpengli@xxxxxxxxxxx> Cc: Jim Mattson <jmattson@xxxxxxxxxx> Cc: Joerg Roedel <joro@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: kvm@xxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx
Reviewed-by: Brijesh Singh <brijesh.singh@xxxxxxx> thanks
