From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:43388) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RvYJd-0001IH-6W for qemu-devel@nongnu.org; Thu, 09 Feb 2012 13:02:01 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RvYJU-0005eG-SS for qemu-devel@nongnu.org; Thu, 09 Feb 2012 13:01:53 -0500 Received: from fmmailgate05.web.de ([217.72.192.243]:44991) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RvYJU-0005e0-KC for qemu-devel@nongnu.org; Thu, 09 Feb 2012 13:01:44 -0500 Received: from moweb002.kundenserver.de (moweb002.kundenserver.de [172.19.20.108]) by fmmailgate05.web.de (Postfix) with ESMTP id 15027695A0B7 for ; Thu, 9 Feb 2012 19:01:43 +0100 (CET) Message-ID: <4F340A04.5080303@web.de> Date: Thu, 09 Feb 2012 19:01:40 +0100 From: Jan Kiszka MIME-Version: 1.0 References: <5c058df627b83bf0c35c2e1dcd92b0a3fd301181.1328445531.git.jan.kiszka@web.de> <4F33E3B3.8000205@redhat.com> <4F33E8C1.3070906@web.de> <4F33EDAD.9020000@redhat.com> <4F33F50C.2050104@web.de> <4F340066.9070108@redhat.com> In-Reply-To: <4F340066.9070108@redhat.com> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig96A3A8182885B0BA790CF018" Subject: Re: [Qemu-devel] [PATCH 3/6] kvmvapic: Introduce TPR access optimization for Windows guests List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: Anthony Liguori , kvm@vger.kernel.org, Gleb Natapov , Marcelo Tosatti , qemu-devel , Avi Kivity This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig96A3A8182885B0BA790CF018 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 2012-02-09 18:20, Paolo Bonzini wrote: > On 02/09/2012 05:32 PM, Jan Kiszka wrote: >> > I mean just check kpcr.self. >> >> Yes, clear, but that means that Windows must have initialized FS.base = to >> point to the KPCR also in UP mode. Is that really the case? E.g. when >> ACPI is off?! I wonder if that explains the reported bug of qemu-kvm >> with -no-acpi and in-kernel irqchip... >=20 > Yes, it does. It's used by some fast-path kernel APIs, and indeed the > canonical way to find the KPCR base from ring 0 is to look at FS:[1Ch].= Yep, can confirm this so far. I briefly tested a non-ACPI installation, and it both works without problems on qemu-kvm and shows that pattern at FS:[1C]. I guess I will simply remove the smp_cpus =3D=3D 1 special case. Jan PS: Please strip of the newsgroups from CC when picking up a thread via news.gmane.org. Some clients may not be configured to reply to them (like mine - intentionally :) ). --------------enig96A3A8182885B0BA790CF018 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/ iEYEARECAAYFAk80CgQACgkQitSsb3rl5xQ75gCg4ypj6p1EgoIpEdRjzpS9wavg b4gAoK/VhqjsyEo7a6hdcWLQ2b8RoBYc =lUR0 -----END PGP SIGNATURE----- --------------enig96A3A8182885B0BA790CF018--