Subject: Re: [PATCH] paravirt.h
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Zachary Amsden <zach@vmware.com>
Cc: Arjan van de Ven <arjan@infradead.org>, Andi Kleen <ak@muc.de>,
       virtualization@lists.osdl.org, Jeremy Fitzhardinge <jeremy@goop.org>,
       Andrew Morton <akpm@osdl.org>, Chris Wright <chrisw@sous-sol.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Date: Tue, 22 Aug 2006 22:36:17 +0100
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Ar Maw, 2006-08-22 am 12:17 -0700, ysgrifennodd Zachary Amsden:
> Possibly an issue, but why would you ever want stacked paravirt-ops?  
> You're only talking to the hypervisor directly above you, and there is 
> only one of those.

Thankfully right now I can't think of a reason other than debugging when
using hardware VMX

> > - If we boot patch inline code to get performance natively its almost
> > impossible to then revert that.

> You can patch back over it.  I've already implemented the locking and 
> repatching bits for VMI.

Ok that bit seemed pretty scary because you have to halt all the
processors in a known state (which probably means in an IPI handler)
before you patch. If you have code thats great.

Alan

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