From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xensource.com>
Subject: Re: [PATCH] Have xen dom0 still handle time of 1970
Date: Wed, 17 Jan 2007 16:16:01 +0000
Message-ID: <C1D3FC41.7C28%keir@xensource.com>
References: <45AE45B7.7030704@redhat.com>
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To: Steven Rostedt <srostedt@redhat.com>, xen-devel@lists.xensource.com
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On 17/1/07 15:50, "Steven Rostedt" <srostedt@redhat.com> wrote:

> Here's what you get without the patch:
> 
> # date -u 010100011970
> Thu Jan  1 00:01:00 UTC 1970
> # date
> Mon Feb 22 16:42:30 EST 2010
> 
> Here's what you get with the patch:
> 
> # date -u 010100011970
> Thu Jan  1 00:01:00 UTC 1970
> # date
> Wed Dec 31 19:01:01 EST 1969

The Xen interface is defined relative to UTC, not local time zone, so
negative numbers shuld not be involved if you are setting a time value after
the epoch (which you are). Perhaps our assumption that xtime is a UTC
variable is broken? If that's the case, is there a way to translate between
local time zone and UTC inside the kernel? If not we have a bit of a problem
since it really makes sense for Xen to work in UTC and let each guest apply
its own time-zone transformation.

 -- Keir