From owner-freebsd-security@FreeBSD.ORG Mon Apr 24 21:50:31 2006 Return-Path: X-Original-To: freebsd-security@freebsd.org Delivered-To: freebsd-security@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id A685D16A405 for ; Mon, 24 Apr 2006 21:50:31 +0000 (UTC) (envelope-from cperciva@freebsd.org) Received: from pd3mo3so.prod.shaw.ca (shawidc-mo1.cg.shawcable.net [24.71.223.10]) by mx1.FreeBSD.org (Postfix) with ESMTP id 4920C43D46 for ; Mon, 24 Apr 2006 21:50:28 +0000 (GMT) (envelope-from cperciva@freebsd.org) Received: from pd3mr1so.prod.shaw.ca (pd3mr1so-qfe3.prod.shaw.ca [10.0.141.177]) by l-daemon (Sun ONE Messaging Server 6.0 HotFix 1.01 (built Mar 15 2004)) with ESMTP id <0IY800JOBY035530@l-daemon> for freebsd-security@freebsd.org; Mon, 24 Apr 2006 15:50:27 -0600 (MDT) Received: from pn2ml10so.prod.shaw.ca ([10.0.121.80]) by pd3mr1so.prod.shaw.ca (Sun ONE Messaging Server 6.0 HotFix 1.01 (built Mar 15 2004)) with ESMTP id <0IY80000MY03T900@pd3mr1so.prod.shaw.ca> for freebsd-security@freebsd.org; Mon, 24 Apr 2006 15:50:27 -0600 (MDT) Received: from [192.168.0.60] ([24.82.18.31]) by l-daemon (Sun ONE Messaging Server 6.0 HotFix 1.01 (built Mar 15 2004)) with ESMTP id <0IY800GNYY029TK1@l-daemon> for freebsd-security@freebsd.org; Mon, 24 Apr 2006 15:50:27 -0600 (MDT) Date: Mon, 24 Apr 2006 14:50:26 -0700 From: Colin Percival In-reply-to: <662E8E58-F87F-4098-B573-06A863B72B7B@lassitu.de> To: Stefan Bethke Message-id: <444D4822.3070102@freebsd.org> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1 Content-transfer-encoding: 7bit X-Enigmail-Version: 0.94.0.0 References: <200604242117.k3OLH2RG032117@repoman.freebsd.org> <662E8E58-F87F-4098-B573-06A863B72B7B@lassitu.de> User-Agent: Thunderbird 1.5 (X11/20060416) Cc: freebsd-security@freebsd.org Subject: Re: cvs commit: src/sys/amd64/amd64 mp_machdep.c src/sys/i386/i386 mp_machdep.c X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Security issues \[members-only posting\]" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 24 Apr 2006 21:50:31 -0000 Stefan Bethke wrote: > Am 24.04.2006 um 23:17 schrieb Colin Percival: >> FreeBSD src repository >> >> Modified files: >> sys/amd64/amd64 mp_machdep.c >> sys/i386/i386 mp_machdep.c > > I do not pretend to understand the background, but from your description > it sounds like performance on Core Duo machines will be bad unless this > change is made, or the potentially dangerous sysctl is active. If that > is indeed the case, will this change make it into 6.1? I'm not part of the release engineering team, but I think they're hoping to merge this before the release, yes. If anyone has a Core Duo system running -CURRENT and can tell me what # sysctl machdep.hyperthreading_allowed # sysctl machdep.hlt_cpus says before and after this change, it would probably speed up the process of merging this into other branches. Colin Percival