From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tristan Gingold <Tristan.Gingold@bull.net>
Date: Thu, 28 Sep 2006 06:55:22 +0000
Subject: Re: [Xen-ia64-devel] Re: ia64 kexec: xen -> linux
Message-Id: <200609280855.22061.Tristan.Gingold@bull.net>
List-Id: <linux-ia64.vger.kernel.org>
References: <200609271152.12393.Tristan.Gingold@bull.net>
In-Reply-To: <200609271152.12393.Tristan.Gingold@bull.net>
MIME-Version: 1.0
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
To: linux-ia64@vger.kernel.org

Le Jeudi 28 Septembre 2006 03:27, Horms a =E9crit :
> On Wed, Sep 27, 2006 at 11:52:12AM +0200, Tristan Gingold wrote:
> > Linux and xen call efi in real mode if set_virtual_address_map fails.
> > You may add an option in both xen and linux to force calling efi in real
> > mode. This should be really simple and you will be able to make progres=
s.
>
> Great, I will test this out and see how it goes.
>
> > The only possible drawback is performance.
>
> What kind of performance issues would you expect?
Making EFI calls in physical mode is slower: Linux must switch from and to =

virtual mode.

However EFI calls are very unfrequent so the impact should be almost nul.

Tristan.