This patchset is also available at: https://github.com/amdese/linux/commits/sev-init2-ghcb-v1 and is based on commit 20cc50a0410f (just before the v13 SNP patches) from: https://git.kernel.org/pub/scm/virt/kvm/kvm.git/log/?h=kvm-coco-queue Overview -------- While the main additions from GHCB protocol version 1 to version 2 revolve mostly around SEV-SNP support, there are a number of changes applicable to SEV-ES guests as well. This series plucks a handful patches from the SNP hypervisor patchset that comprise the total set of GHCB-related changes that are also applicable to SEV-ES, and then introduces a KVM_SEV_INIT2 field so that userspace can control the maximum GHCB protocol version advertised to guests to help manage compatibility across kernels/versions. For more background discussion, see: https://lore.kernel.org/kvm/ZimnngU7hn7sKoSc@xxxxxxxxxx/ Patch Layout ------------ 01-03: These patches add support for all version 2 GHCB requests that are applicable to SEV-ES 04: This patch switches the KVM_SEV_INIT2 default to GHCB protocol version 2, and extends it with a new parameter that userspace can use to control the specific GHCB version for a guest Testing ------- For testing this via QEMU, use the following tree: https://github.com/amdese/qemu/commits/snp-v4-wip3c A basic command-line invocation for SEV-ES would be: qemu-system-x86_64 -smp 32,maxcpus=255 -cpu EPYC-Milan-v2 -machine q35,confidential-guest-support=sev0 -object sev-guest,id=sev0,cbitpos=51,reduced-phys-bits=1,ghcb-version=2 Feedback/review is very much appreciated. -Mike ---------------------------------------------------------------- Brijesh Singh (1): KVM: SEV: Add GHCB handling for Hypervisor Feature Support requests Michael Roth (2): KVM: SEV: Add GHCB handling for termination requests KVM: SEV: Allow per-guest configuration of GHCB protocol version Tom Lendacky (1): KVM: SEV: Add support to handle AP reset MSR protocol Documentation/virt/kvm/x86/amd-memory-encryption.rst | 11 ++++- arch/x86/include/asm/sev-common.h | 8 +++- arch/x86/include/uapi/asm/kvm.h | 4 +- arch/x86/kvm/svm/sev.c | 111 ++++++++++++++++++++++++++++++++++++++++----- arch/x86/kvm/svm/svm.h | 2 + 5 files changed, 120 insertions(+), 16 deletions(-)