Monitor/QMP: Don't allow cont on bad VM state

We have two states where issuing cont before system_reset can
cause problems: RSTATE_SHUTDOWN (when -no-shutdown is used) and
RSTATE_PANICKED (which only happens with kvm).

This commit fixes that by doing the following when state is
RSTATE_SHUTDOWN or RSTATE_PANICKED:

 1. returning an error to the user/client if cont is issued
 2. automatically transition to RSTATE_PAUSED during system_reset

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

diff --git a/monitor.c b/monitor.c
index 442b4cf01d79f619b15af3fb601195db6cb4ab59..ac68edf98b6abab9b5fc421379ab8598ebd9e1c9 100644 (file)
--- a/monitor.c
+++ b/monitor.c
@@ -1314,7 +1314,12 @@ static int do_cont(Monitor *mon, const QDict *qdict, QObject **ret_data)
     if (runstate_check(RSTATE_IN_MIGRATE)) {
         qerror_report(QERR_MIGRATION_EXPECTED);
         return -1;
+    } else if (runstate_check(RSTATE_PANICKED) ||
+               runstate_check(RSTATE_SHUTDOWN)) {
+        qerror_report(QERR_RESET_REQUIRED);
+        return -1;
     }
+
     bdrv_iterate(encrypted_bdrv_it, &context);
     /* only resume the vm if all keys are set and valid */
     if (!context.err) {

diff --git a/qerror.c b/qerror.c
index 3d64b80b24a6363006eda8d410bb7e8e5f7e2485..c591a5443cedb4d3d85dae95218edbd44d5aeb6e 100644 (file)
--- a/qerror.c
+++ b/qerror.c
@@ -193,6 +193,10 @@ static const QErrorStringTable qerror_table[] = {
         .error_fmt = QERR_QMP_EXTRA_MEMBER,
         .desc      = "QMP input object member '%(member)' is unexpected",
     },
+    {
+        .error_fmt = QERR_RESET_REQUIRED,
+        .desc      = "Resetting the Virtual Machine is required",
+    },
     {
         .error_fmt = QERR_SET_PASSWD_FAILED,
         .desc      = "Could not set password",

diff --git a/qerror.h b/qerror.h
index 8058456d2e831ffbb15a019849d0e53b16adceda..d4070015f726d80e3a88a6f5990df1da853b4e15 100644 (file)
--- a/qerror.h
+++ b/qerror.h
@@ -163,6 +163,9 @@ QError *qobject_to_qerror(const QObject *obj);
 #define QERR_QMP_EXTRA_MEMBER \
     "{ 'class': 'QMPExtraInputObjectMember', 'data': { 'member': %s } }"
 
+#define QERR_RESET_REQUIRED \
+    "{ 'class': 'ResetRequired', 'data': {} }"
+
 #define QERR_SET_PASSWD_FAILED \
     "{ 'class': 'SetPasswdFailed', 'data': {} }"
 

diff --git a/vl.c b/vl.c
index 9128d48fea7986c2b252473b7d37d72e82283a0a..686e491e9aeafc1df05aa87509e23490b55c4e64 100644 (file)
--- a/vl.c
+++ b/vl.c
@@ -1573,6 +1573,10 @@ static void main_loop(void)
             cpu_synchronize_all_states();
             qemu_system_reset(VMRESET_REPORT);
             resume_all_vcpus();
+            if (runstate_check(RSTATE_PANICKED) ||
+                runstate_check(RSTATE_SHUTDOWN)) {
+                runstate_set(RSTATE_PAUSED);
+            }
         }
         if (qemu_powerdown_requested()) {
             monitor_protocol_event(QEVENT_POWERDOWN, NULL);