Single PV startup vs multiple PV startup

[zach at vmware.com (Zachary Amsden)]

Zachary Amsden wrote:
> Jeremy Fitzhardinge wrote:
>   
>>>   When combined with Zach's "share startup_32" patch, I
>>> think it's a no-brainer.
>>>   
>>>       
>> Actually, that's a non-starter.  It won't work if the kernel is 
>> running in ring 0.
>>     
>
>   

Doesn't this work and give a common entry point with the regular kernel, 
eliminating all the need for string processing?

--- .pc/head-S-common-entry/arch/i386/kernel/head.S     2006-07-28 
00:02:12.000000000 -0700
+++ arch/i386/kernel/head.S     2006-07-28 00:04:43.000000000 -0700
@@ -54,6 +54,12 @@
  * can.
  */
 ENTRY(startup_32)
+
+#ifdef CONFIG_PARAVIRT
+       mov %cr0, %ecx
+       test %ecx, %ecx
+       js pv_startup_32
+#endif

 /*
  * Set segments to known values.