On 20/04/21 01:06, Sean Christopherson wrote:
diff --git a/arch/x86/include/uapi/asm/kvm_para.h b/arch/x86/include/uapi/asm/kvm_para.h
index 950afebfba88..f6bfa138874f 100644
--- a/arch/x86/include/uapi/asm/kvm_para.h
+++ b/arch/x86/include/uapi/asm/kvm_para.h
@@ -33,6 +33,7 @@
#define KVM_FEATURE_PV_SCHED_YIELD 13
#define KVM_FEATURE_ASYNC_PF_INT 14
#define KVM_FEATURE_MSI_EXT_DEST_ID 15
+#define KVM_FEATURE_SEV_LIVE_MIGRATION 16
#define KVM_HINTS_REALTIME 0
@@ -54,6 +55,7 @@
#define MSR_KVM_POLL_CONTROL 0x4b564d05
#define MSR_KVM_ASYNC_PF_INT 0x4b564d06
#define MSR_KVM_ASYNC_PF_ACK 0x4b564d07
+#define MSR_KVM_SEV_LIVE_MIGRATION 0x4b564d08
struct kvm_steal_time {
__u64 steal;
@@ -136,4 +138,6 @@ struct kvm_vcpu_pv_apf_data {
#define KVM_PV_EOI_ENABLED KVM_PV_EOI_MASK
#define KVM_PV_EOI_DISABLED 0x0
+#define KVM_SEV_LIVE_MIGRATION_ENABLED BIT_ULL(0)
Even though the intent is to "force" userspace to intercept the MSR, I think KVM
should at least emulate the legal bits as a nop. Deferring completely to
userspace is rather bizarre as there's not really anything to justify KVM
getting involved. It would also force userspace to filter the MSR just to
support the hypercall.
I think this is the intention, the hypercall by itself cannot do much if
you cannot tell userspace that it's up-to-date.
On the other hand it is kind of wrong that KVM_GET_SUPPORTED_CPUID
returns the feature, but the MSR is not supported.
Somewhat of a nit, but I think we should do something like s/ENABLED/READY,
Agreed. I'll send a patch that puts everything together.
Paolo
