[PATCH V1 1/3] vl: start on wakeup request

[Steve Sistare]

If qemu starts and loads a VM in the suspended state, then a later wakeup
request sets the state to running and tries to start execution, but it
bypasses vm_start() and its initialization steps, which is fatal for the
guest.  See qemu_system_wakeup_request(), and qemu_system_wakeup() in
main_loop_should_exit().

Define the start_on_wakeup_requested() hook to cause vm_start() to be called
when processing the wakeup request.  This will be called in a subsequent
migration patch.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
---
 include/sysemu/runstate.h |  1 +
 softmmu/runstate.c        | 15 ++++++++++++++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/include/sysemu/runstate.h b/include/sysemu/runstate.h
index 7beb29c..c12ad7d 100644
--- a/include/sysemu/runstate.h
+++ b/include/sysemu/runstate.h
@@ -57,6 +57,7 @@ void qemu_system_reset_request(ShutdownCause reason);
 void qemu_system_suspend_request(void);
 void qemu_register_suspend_notifier(Notifier *notifier);
 bool qemu_wakeup_suspend_enabled(void);
+void qemu_system_start_on_wakeup_request(void);
 void qemu_system_wakeup_request(WakeupReason reason, Error **errp);
 void qemu_system_wakeup_enable(WakeupReason reason, bool enabled);
 void qemu_register_wakeup_notifier(Notifier *notifier);
diff --git a/softmmu/runstate.c b/softmmu/runstate.c
index 1957caf..e127b21 100644
--- a/softmmu/runstate.c
+++ b/softmmu/runstate.c
@@ -343,6 +343,7 @@ void vm_state_notify(bool running, RunState state)
     }
 }
 
+static bool start_on_wakeup_requested;
 static ShutdownCause reset_requested;
 static ShutdownCause shutdown_requested;
 static int shutdown_signal;
@@ -568,6 +569,11 @@ void qemu_register_suspend_notifier(Notifier *notifier)
     notifier_list_add(&suspend_notifiers, notifier);
 }
 
+void qemu_system_start_on_wakeup_request(void)
+{
+    start_on_wakeup_requested = true;
+}
+
 void qemu_system_wakeup_request(WakeupReason reason, Error **errp)
 {
     trace_system_wakeup_request(reason);
@@ -580,7 +586,14 @@ void qemu_system_wakeup_request(WakeupReason reason, Error 
**errp)
     if (!(wakeup_reason_mask & (1 << reason))) {
         return;
     }
-    runstate_set(RUN_STATE_RUNNING);
+
+    if (start_on_wakeup_requested) {
+        start_on_wakeup_requested = false;
+        vm_start();
+    } else {
+        runstate_set(RUN_STATE_RUNNING);
+    }
+
     wakeup_reason = reason;
     qemu_notify_event();
 }
-- 
1.8.3.1