[Qemu-devel] [PATCH 3/4] target/i386: kvm: Save nested-state only in case vCPU have set VMXON region

[Liran Alon]

Having (nested_state->hdr.vmx.vmxon_pa != -1ull) signals that vCPU have set
at some point in time a VMXON region. Note that even though when vCPU enters
SMM mode it temporarily exit VMX operation, KVM still reports (vmxon_pa != 
-1ull).
Therefore, this field can be used as a reliable indicator on when we require to
send VMX nested-state as part of migration stream.

Reviewed-by: Joao Martins <address@hidden>
Signed-off-by: Liran Alon <address@hidden>
---
 target/i386/machine.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/target/i386/machine.c b/target/i386/machine.c
index 851b249d1a39..20bda9f80154 100644
--- a/target/i386/machine.c
+++ b/target/i386/machine.c
@@ -997,9 +997,8 @@ static bool vmx_nested_state_needed(void *opaque)
 {
     struct kvm_nested_state *nested_state = opaque;
 
-    return ((nested_state->format == KVM_STATE_NESTED_FORMAT_VMX) &&
-            ((nested_state->hdr.vmx.vmxon_pa != -1ull) ||
-             (nested_state->hdr.vmx.smm.flags & KVM_STATE_NESTED_SMM_VMXON)));
+    return (nested_state->format == KVM_STATE_NESTED_FORMAT_VMX) &&
+           (nested_state->hdr.vmx.vmxon_pa != -1ull);
 }
 
 static const VMStateDescription vmstate_vmx_nested_state = {
-- 
2.20.1