qemu.py: include debug information on launch error

When launching a VM, if an exception happens and the VM is not initiated, it might be useful to see the qemu command line and the qemu command output. This patch creates that message. Notice that self._iolog needs to be cleaned up in the beginning of the launch() to make sure we will not expose the qemu log from a previous launch if the current one fails. Signed-off-by: Amador Pahim <[email protected]> Message-Id: <[email protected]> Reviewed-by: Fam Zheng <[email protected]> Signed-off-by: Eduardo Habkost <[email protected]>
dreddy · Sep 15, 2017 · b92a001 · b92a001
1 parent dab91d9
commit b92a001
Showing 1 changed file with 7 additions and 0 deletions.
diff --git a/scripts/qemu.py b/scripts/qemu.py
@@ -187,6 +187,7 @@ def _post_shutdown(self):
 
     def launch(self):
         '''Launch the VM and establish a QMP connection'''
+        self._iolog = None
         self._qemu_full_args = None
         devnull = open(os.path.devnull, 'rb')
         qemulog = open(self._qemu_log_path, 'wb')
@@ -206,6 +207,12 @@ def launch(self):
                 self._popen.wait()
             self._load_io_log()
             self._post_shutdown()
+
+            LOG.debug('Error launching VM')
+            if self._qemu_full_args:
+                LOG.debug('Command: %r', ' '.join(self._qemu_full_args))
+            if self._iolog:
+                LOG.debug('Output: %r', self._iolog)
             raise
 
     def shutdown(self):