Re: Should Qemu monitor be enabled by default

["Daniel P. Berrange" <berrange@redhat.com>]

On Thu, Apr 12, 2007 at 02:40:23PM +0800, You, Yongkang wrote:
> Hi Christian,
> 
> We worked out a simple patch and tried it well. Please apply. 

This part of the patch does not look correct:

-- a/tools/python/xen/xend/image.py	Thu Apr 12 13:18:08 2007 +0100
+++ b/tools/python/xen/xend/image.py	Thu Apr 12 13:21:26 2007 +0100
@@ -415,6 +415,8 @@ class HVMImageHandler(ImageHandler):
         else:
             ret.append('-nographic')
 
+        if int(vmConfig['platform'].get('monitor', 0)) != 0:
+            ret.append('-monitor vc')
         return ret
 
     def createDeviceModel(self, restore = False):

The '-monitor vc' is already the default for QEMU, so both branches of
that if end up reducing to the same functional state - the monitor being
enabled. You need to explicitly disable the monitor if the config file 
has monitor=0

I'm not sure this patch is a good idea long term though. If, as Anthony
suggests in previous thread, XenD takes control of the monitor and provides
an explicit 'xm monitor' command, then it'll be impossible to also make
the monitor also appear on a VC. 

This also doesn't address the issue that making the monitor appear on a
VC is fundamentally a security risk and so can never be enabled in any
production environment where you care about integrity of the Dom0 host. 
I don't see the point in introducing a config file setting which will 
have to go away once a sustainable 'xm monitor' patch is implemented.

For the timescales involved in 3.0.5 I think we should instead make sure
that 'xm block-configure' works correctly.

Dan
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