kvm: x86: Use separate exception_injected CPUState field

Marcelo correctly remarked that there are usage conflicts between QEMU
core code and KVM /wrt exception_index. So spend a separate field and
also save/restore it properly.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

target-i386/cpu.h

@@ -694,6 +694,7 @@ typedef struct CPUX86State {
 
     /* For KVM */
     uint32_t mp_state;
+    int32_t exception_injected;
     int32_t interrupt_injected;
     uint8_t soft_interrupt;
     uint8_t nmi_injected;

target-i386/kvm.c

@@ -720,8 +720,8 @@ static int kvm_put_vcpu_events(CPUState *env)
         return 0;
     }
 
-    events.exception.injected = (env->exception_index >= 0);
-    events.exception.nr = env->exception_index;
+    events.exception.injected = (env->exception_injected >= 0);
+    events.exception.nr = env->exception_injected;
     events.exception.has_error_code = env->has_error_code;
     events.exception.error_code = env->error_code;
 
@@ -755,7 +755,7 @@ static int kvm_get_vcpu_events(CPUState *env)
     if (ret < 0) {
        return ret;
     }
-    env->exception_index =
+    env->exception_injected =
        events.exception.injected ? events.exception.nr : -1;
     env->has_error_code = events.exception.has_error_code;
     env->error_code = events.exception.error_code;

target-i386/machine.c

@@ -448,6 +448,7 @@ static const VMStateDescription vmstate_cpu = {
         VMSTATE_INT32_V(interrupt_injected, CPUState, 9),
         VMSTATE_UINT32_V(mp_state, CPUState, 9),
         VMSTATE_UINT64_V(tsc, CPUState, 9),
+        VMSTATE_INT32_V(exception_injected, CPUState, 11),
         VMSTATE_UINT8_V(soft_interrupt, CPUState, 11),
         VMSTATE_UINT8_V(nmi_injected, CPUState, 11),
         VMSTATE_UINT8_V(nmi_pending, CPUState, 11),