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Re: [Xen-devel] Where is xtime updated in a domU with an independent wal

To: Jay Patel <nitrofin@xxxxxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] Where is xtime updated in a domU with an independent wallclock?
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Wed, 02 May 2007 08:16:01 +0100
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On 2/5/07 07:41, "Jay Patel" <nitrofin@xxxxxxxxx> wrote:

I have just started looking at the code for Xen so please bear with me.
 
A domU Linux kernel running with independent_wallclock=1 seems to sync its  time with dom0 after every "xm unpause" (obviously preceded by an "xm  pause").
 
I don't see where the xtime variable is being updated after an "xm unpause",  i.e., domain_unpause_by_systemcontroller(). Right after the unpause, it seems to  me that the xtime in the domU should be what it were just prior to the  pause.

Yes, a guest with independent wallclock should never sync with the wallclock time record provided by Xen, even after an unpause (the unpause is not explicitly visible to the guest anyway).

 -- Keir
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