From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: kvm's vapic Date: Sun, 29 Jan 2012 16:37:18 +0100 Message-ID: <4F2567AE.8000509@web.de> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig8D30AED82E9DBA2B37E1F8BE" Cc: kvm To: Avi Kivity , Marcelo Tosatti , Gleb Natapov Return-path: Received: from fmmailgate03.web.de ([217.72.192.234]:56970 "EHLO fmmailgate03.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753013Ab2A2PhX (ORCPT ); Sun, 29 Jan 2012 10:37:23 -0500 Received: from moweb001.kundenserver.de (moweb001.kundenserver.de [172.19.20.114]) by fmmailgate03.web.de (Postfix) with ESMTP id E40751B0843FE for ; Sun, 29 Jan 2012 16:37:21 +0100 (CET) Sender: kvm-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig8D30AED82E9DBA2B37E1F8BE Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Hi all, I'm studying the TPR access optimization in qemu-kvm for quite a while now. It's one of the, well, let's call it "hardest" parts of qemu-kvm I dealt with so far. But it's slowly getting clearer. One thing I'm wondering now: This is practically targeting only 32-bit Windows, right? Already the assumption that we find a CPU index at fs:0x51 is apparently hard-coding this. Or that kernel code is at 0x8xxxxxxx or 0xExxxxxxx. But what makes sure that we aren't patching some other obscure OS that doesn't comply with our assumptions but triggers the TPR access reports nevertheless? Is there a way to detect the supported target OSes reliably before patching anything? Otherwise this feature has to remain off by default in upstream, I suppose. Jan --------------enig8D30AED82E9DBA2B37E1F8BE Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.16 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk8lZ68ACgkQitSsb3rl5xRzIgCgo8vHZGJgTzMOVGbLg7PeMcoW BV4AoK+PysTqDL738t1DplCbfdl7uLrz =cPcV -----END PGP SIGNATURE----- --------------enig8D30AED82E9DBA2B37E1F8BE--