AMD SEV encrypts the memory of VMs and because this encryption is done using an address tweak, the hypervisor will not be able to simply copy ciphertext between machines to migrate a VM. Instead the AMD SEV Key Management API provides a set of functions which the hypervisor can use to package a guest encrypted pages for migration, while maintaining the confidentiality provided by AMD SEV.
The patch series add the support required in Qemu to perform the SEV guest live migration. Before initiating the live migration a user should use newly added 'migrate-set-sev-info' command to pass the target machines certificate chain. See the docs/amd-memory-encryption.txt for further details. The patch series depends on kernel patches available here: https://marc.info/?l=kvm&m=156278967226011&w=2 The complete tree with patch is available at: https://github.com/codomania/qemu/tree/sev-migration-v2 Changes since v1: - use the dirty log sync APIs to also sync the page encryption bitmap when SEV is active. Brijesh Singh (13): linux-headers: update kernel header to include SEV migration commands kvm: introduce high-level API to support encrypted page migration migration/ram: add support to send encrypted pages kvm: add support to sync the page encryption state bitmap doc: update AMD SEV API spec web link doc: update AMD SEV to include Live migration flow target/i386: sev: do not create launch context for an incoming guest misc.json: add migrate-set-sev-info command target/i386: sev: add support to encrypt the outgoing page target/i386: sev: add support to load incoming encrypted page kvm: introduce high-level API to migrate the page encryption bitmap migration: add support to migrate page encryption bitmap target/i386: sev: remove migration blocker accel/kvm/kvm-all.c | 108 ++++++++ accel/kvm/sev-stub.c | 22 ++ accel/stubs/kvm-stub.c | 22 ++ docs/amd-memory-encryption.txt | 44 +++- include/exec/ram_addr.h | 161 +++++++++++- include/exec/ramlist.h | 3 +- include/sysemu/kvm.h | 25 ++ include/sysemu/sev.h | 6 + linux-headers/linux/kvm.h | 53 ++++ migration/ram.c | 91 ++++++- qapi/misc-target.json | 18 ++ target/i386/monitor.c | 10 + target/i386/sev-stub.c | 5 + target/i386/sev.c | 455 +++++++++++++++++++++++++++++++-- target/i386/sev_i386.h | 11 +- target/i386/trace-events | 8 + 16 files changed, 1016 insertions(+), 26 deletions(-) -- 2.17.1