[PATCH -v3] Add savevm/loadvm support for MCE

[Huang Ying <ying.huang@intel.com>]

MCE registers are saved/load into/from CPUState in
kvm_arch_save/load_regs. To simulate the MCG_STATUS clearing upon
reset, MSR_MCG_STATUS is set to 0 for KVM_PUT_RESET_STATE.

v3:

 - use msrs[] in kvm_arch_load/save_regs and get_msr_entry directly.

v2:

 - Rebased on new CPU registers save/load framework.

Signed-off-by: Huang Ying <ying.huang@intel.com>
---
 qemu-kvm-x86.c |   36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

--- a/qemu-kvm-x86.c
+++ b/qemu-kvm-x86.c
@@ -748,7 +748,22 @@ static int get_msr_entry(struct kvm_msr_
         case MSR_KVM_WALL_CLOCK:
             env->wall_clock_msr = entry->data;
             break;
+#ifdef KVM_CAP_MCE
+        case MSR_MCG_STATUS:
+            env->mcg_status = entry->data;
+            break;
+        case MSR_MCG_CTL:
+            env->mcg_ctl = entry->data;
+            break;
+#endif
         default:
+#ifdef KVM_CAP_MCE
+            if (entry->index >= MSR_MC0_CTL && \
+                entry->index < MSR_MC0_CTL + (env->mcg_cap & 0xff) * 4) {
+                env->mce_banks[entry->index - MSR_MC0_CTL] = entry->data;
+                break;
+            }
+#endif
             printf("Warning unknown msr index 0x%x\n", entry->index);
             return 1;
         }
@@ -979,6 +994,18 @@ void kvm_arch_load_regs(CPUState *env, i
         set_msr_entry(&msrs[n++], MSR_KVM_SYSTEM_TIME, env->system_time_msr);
         set_msr_entry(&msrs[n++], MSR_KVM_WALL_CLOCK, env->wall_clock_msr);
     }
+#ifdef KVM_CAP_MCE
+    if (env->mcg_cap) {
+        if (level == KVM_PUT_RESET_STATE)
+            set_msr_entry(&msrs[n++], MSR_MCG_STATUS, env->mcg_status);
+        else if (level == KVM_PUT_FULL_STATE) {
+            set_msr_entry(&msrs[n++], MSR_MCG_STATUS, env->mcg_status);
+            set_msr_entry(&msrs[n++], MSR_MCG_CTL, env->mcg_ctl);
+            for (i = 0; i < (env->mcg_cap & 0xff); i++)
+                set_msr_entry(&msrs[n++], MSR_MC0_CTL + i, env->mce_banks[i]);
+        }
+    }
+#endif
 
     rc = kvm_set_msrs(env, msrs, n);
     if (rc == -1)
@@ -1144,6 +1171,15 @@ void kvm_arch_save_regs(CPUState *env)
     msrs[n++].index = MSR_KVM_SYSTEM_TIME;
     msrs[n++].index = MSR_KVM_WALL_CLOCK;
 
+#ifdef KVM_CAP_MCE
+    if (env->mcg_cap) {
+        msrs[n++].index = MSR_MCG_STATUS;
+        msrs[n++].index = MSR_MCG_CTL;
+        for (i = 0; i < (env->mcg_cap & 0xff) * 4; i++)
+            msrs[n++].index = MSR_MC0_CTL + i;
+    }
+#endif
+
     rc = kvm_get_msrs(env, msrs, n);
     if (rc == -1) {
         perror("kvm_get_msrs FAILED");