From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by 10.25.208.211 with SMTP id h202csp2516963lfg; Wed, 9 Mar 2016 06:07:34 -0800 (PST) X-Received: by 10.55.75.144 with SMTP id y138mr43501381qka.96.1457532452509; Wed, 09 Mar 2016 06:07:32 -0800 (PST) Return-Path: Received: from lists.gnu.org (lists.gnu.org. [2001:4830:134:3::11]) by mx.google.com with ESMTPS id z7si8076022qhb.22.2016.03.09.06.07.32 for (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 09 Mar 2016 06:07:32 -0800 (PST) Received-SPF: pass (google.com: domain of qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org designates 2001:4830:134:3::11 as permitted sender) client-ip=2001:4830:134:3::11; Authentication-Results: mx.google.com; spf=pass (google.com: domain of qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org designates 2001:4830:134:3::11 as permitted sender) smtp.mailfrom=qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org Received: from localhost ([::1]:41752 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1adelv-0003WX-Vl for alex.bennee@linaro.org; Wed, 09 Mar 2016 09:07:31 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59633) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1adelu-0003WR-Jo for qemu-arm@nongnu.org; Wed, 09 Mar 2016 09:07:31 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1adelt-00049I-Hr for qemu-arm@nongnu.org; Wed, 09 Mar 2016 09:07:30 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40152) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1adelt-00048w-CW; Wed, 09 Mar 2016 09:07:29 -0500 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (Postfix) with ESMTPS id 1AE89AA0B0; Wed, 9 Mar 2016 14:07:29 +0000 (UTC) Received: from [10.36.112.60] (ovpn-112-60.ams2.redhat.com [10.36.112.60]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u29E7PAU006079 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 9 Mar 2016 09:07:26 -0500 To: Laszlo Ersek , Ard Biesheuvel References: <1455288361-30117-1-git-send-email-peter.maydell@linaro.org> <56DD9C58.7050306@redhat.com> <56DEBF6A.6070809@redhat.com> <56DEC234.70907@redhat.com> <56DEC860.1060707@redhat.com> <56DECE5F.6000207@redhat.com> <56E02DCD.5060008@redhat.com> From: Paolo Bonzini Message-ID: <56E02E1C.2090207@redhat.com> Date: Wed, 9 Mar 2016 15:07:24 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <56E02DCD.5060008@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: Peter Maydell , qemu-arm , QEMU Developers , Markus Armbruster , "Michael S. Tsirkin" Subject: Re: [Qemu-arm] [Qemu-devel] [PATCH 0/4] virt: provide secure-only RAM and first flash X-BeenThere: qemu-arm@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org Sender: qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org X-TUID: kZeOYwAkZD6I On 09/03/2016 15:06, Laszlo Ersek wrote: > However: despite reusing the core SMM code identically in the guest, > there is at least one stark behavioral difference: in QEMU the SMI is > raised only on the processor that triggers it. This exercises paths in > the core SMM code where processors have to count down timeouts and bring > each other in, and these busy loops are very visible to an interactive > user in certain circumstances. Right, and that's unfortunately something that's hard to change because SeaBIOS relies on it. :(( Paolo From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59653) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1adelw-0003Xu-Rk for qemu-devel@nongnu.org; Wed, 09 Mar 2016 09:07:39 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1adelv-0004A5-Dt for qemu-devel@nongnu.org; Wed, 09 Mar 2016 09:07:32 -0500 References: <1455288361-30117-1-git-send-email-peter.maydell@linaro.org> <56DD9C58.7050306@redhat.com> <56DEBF6A.6070809@redhat.com> <56DEC234.70907@redhat.com> <56DEC860.1060707@redhat.com> <56DECE5F.6000207@redhat.com> <56E02DCD.5060008@redhat.com> From: Paolo Bonzini Message-ID: <56E02E1C.2090207@redhat.com> Date: Wed, 9 Mar 2016 15:07:24 +0100 MIME-Version: 1.0 In-Reply-To: <56E02DCD.5060008@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 0/4] virt: provide secure-only RAM and first flash List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Laszlo Ersek , Ard Biesheuvel Cc: Peter Maydell , qemu-arm , QEMU Developers , Markus Armbruster , "Michael S. Tsirkin" On 09/03/2016 15:06, Laszlo Ersek wrote: > However: despite reusing the core SMM code identically in the guest, > there is at least one stark behavioral difference: in QEMU the SMI is > raised only on the processor that triggers it. This exercises paths in > the core SMM code where processors have to count down timeouts and bring > each other in, and these busy loops are very visible to an interactive > user in certain circumstances. Right, and that's unfortunately something that's hard to change because SeaBIOS relies on it. :(( Paolo