Date: Thu, 9 Aug 2007 10:37:21 -0400 (EDT)
From: Steven Rostedt <rostedt@goodmis.org>
To: Andi Kleen <ak@suse.de>
cc: Jeremy Fitzhardinge <jeremy@goop.org>,
       Glauber de Oliveira Costa <gcosta@redhat.com>,
       linux-kernel@vger.kernel.org, akpm@linux-foundation.org,
       rusty@rustcorp.com.au, mingo@elte.hu, chrisw@sous-sol.org,
       avi@qumranet.com, anthony@codemonkey.ws,
       virtualization@lists.linux-foundation.org, lguest@ozlabs.org
Subject: Re: [PATCH 25/25] [PATCH] add paravirtualization support for x86_64
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--
On Thu, 9 Aug 2007, Andi Kleen wrote:
>
> > This has to match the normal C calling convention though, doesn't it?
>
> Native cli/sti/save/restore_flags are all only assembly and can be easily
> (in fact more easily than in C) written as pure assembler functions. Then
> you can use whatever calling convention you want.

I agree.
Should we make a paravirt_ops_asm.S file that can implement these native
funcions, and so we can get rid of the C functions only doing asm?

>
> While some paravirt implementations may have more complicated implementations
> i guess it's still a reasonable requirement to make them simple enough
> in pure assembler. If not they can use a trampoline, but that's hopefully
> not needed.

It works for lguest64.  I'm sure it should be no problem with other HVs.

-- Steve

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