From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: [patch 13/21] Xen-paravirt: Add nosegneg capability
 to the vsyscall page notes
Date: Tue, 13 Feb 2007 14:49:10 -0800
Message-ID: <45D24066.4070109@goop.org>
References: <20070213221729.772002682@goop.org>
	<20070213221830.466651996@goop.org> <45D23F97.5040907@vmware.com>
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To: Zachary Amsden <zach@vmware.com>
Cc: Andrew Morton <akpm@osdl.org>, xen-devel@lists.xensource.com, Ian Pratt <ian.pratt@xensource.com>, virtualization@lists.osdl.org, linux-kernel@vger.kernel.org, Chris Wright <chrisw@sous-sol.org>, Andi Kleen <ak@muc.de>, Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
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Zachary Amsden wrote:
> I don't like this because now a kernel compiled with both CONFIG_XEN
> and CONFIG_VMI has "nosegneg" turned on.  We don't actually require
> this for performance or correctness, so it would be nice to be able to
> dynamically turn it off instead of having it forced. 

Any suggestions about how to do this?  It seems hard to have a note
dynamically appear and disappear in the vsyscall.so.

I wasn't terribly concerned about this, since there is effectively zero
performance difference between the two library implementations.

    J