target-i386: seperate MCIP & MCE_MASK error reason

Previously we would only get a simple string "Triple fault" in qemu
log. Add detailed message for the two reasons to describe why qemu
has to reset the guest.

Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Message-Id: <20200930100440.1060708-2-pizhenwei@bytedance.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

target/i386/helper.c

@@ -857,6 +857,8 @@ static void do_inject_x86_mce(CPUState *cs, run_on_cpu_data data)
     X86CPU *cpu = X86_CPU(cs);
     CPUX86State *cenv = &cpu->env;
     uint64_t *banks = cenv->mce_banks + 4 * params->bank;
+    g_autofree char *msg = NULL;
+    bool need_reset = false;
 
     cpu_synchronize_state(cs);
 
@@ -894,16 +896,25 @@ static void do_inject_x86_mce(CPUState *cs, run_on_cpu_data data)
             return;
         }
 
-        if ((cenv->mcg_status & MCG_STATUS_MCIP) ||
-            !(cenv->cr[4] & CR4_MCE_MASK)) {
-            monitor_printf(params->mon,
-                           "CPU %d: Previous MCE still in progress, raising"
-                           " triple fault\n",
-                           cs->cpu_index);
-            qemu_log_mask(CPU_LOG_RESET, "Triple fault\n");
+        if (cenv->mcg_status & MCG_STATUS_MCIP) {
+            need_reset = true;
+            msg = g_strdup_printf("CPU %d: Previous MCE still in progress, "
+                                  "raising triple fault", cs->cpu_index);
+        }
+
+        if (!(cenv->cr[4] & CR4_MCE_MASK)) {
+            need_reset = true;
+            msg = g_strdup_printf("CPU %d: MCE capability is not enabled, "
+                                  "raising triple fault", cs->cpu_index);
+        }
+
+        if (need_reset) {
+            monitor_printf(params->mon, "%s", msg);
+            qemu_log_mask(CPU_LOG_RESET, "%s\n", msg);
             qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
             return;
         }
+
         if (banks[1] & MCI_STATUS_VAL) {
             params->status |= MCI_STATUS_OVER;
         }