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[Xen-devel] [PATCH] Add a safety valve to the HVM RTC model for big time

from [Tim Deegan]

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Subject:	[Xen-devel] [PATCH] Add a safety valve to the HVM RTC model for big time jumps
From:	Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Date:	Wed, 2 Jun 2010 11:19:06 +0100
Delivery-date:	Wed, 02 Jun 2010 03:27:02 -0700
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If xen's time leaps forward by a large amount, the RTC will try to model
a tick for every second that it thinks has passed.  This can livelock a
CPU with a series of timer requests each of which fires immediately and
requests the next one.

This patch treats a delay of more than a day between ticks as a special
case, abandoning the attempt to catch up.  That should be good enough to
avoid livelock but doesn't fix the underlying time problem.

Signed-off-by: Tim Deegan <Tim.Deegan@xxxxxxxxxx>

xen-unstable.hg.patch
Description: Text Data

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