SEV-capable VMs may also use the KVM_X86_SW_PROTECTED_VM type, but they will still need architecture-specific handling to move encryption context. Hence, we let moving of encryption context be configurable and store that configuration in a flag.
Co-developed-by: Vishal Annapurve vannapurve@google.com Signed-off-by: Vishal Annapurve vannapurve@google.com Signed-off-by: Ackerley Tng ackerleytng@google.com --- arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/kvm/svm/sev.c | 2 ++ arch/x86/kvm/x86.c | 9 ++++++++- 3 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 71c1236e4f18..ab45a3d3c867 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1445,6 +1445,8 @@ struct kvm_arch { */ #define SPLIT_DESC_CACHE_MIN_NR_OBJECTS (SPTE_ENT_PER_PAGE + 1) struct kvm_mmu_memory_cache split_desc_cache; + + bool vm_move_enc_ctxt_supported; };
struct kvm_vm_stat { diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index e0e206aa3e62..b09e6477e309 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -256,6 +256,8 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) goto e_no_asid; sev->asid = asid;
+ kvm->arch.vm_move_enc_ctxt_supported = true; + ret = sev_platform_init(&argp->error); if (ret) goto e_free; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 75d48379d94d..a1a28dd77b94 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6351,7 +6351,14 @@ static int kvm_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) if (r) goto out_mark_migration_done;
- r = static_call(kvm_x86_vm_move_enc_context_from)(kvm, source_kvm); + /* + * Different types of VMs will allow userspace to define if moving + * encryption context should be supported. + */ + if (kvm->arch.vm_move_enc_ctxt_supported && + kvm_x86_ops.vm_move_enc_context_from) { + r = static_call(kvm_x86_vm_move_enc_context_from)(kvm, source_kvm); + }
kvm_unlock_two_vms(kvm, source_kvm); out_mark_migration_done: