From owner-cvs-src@FreeBSD.ORG Tue Oct 7 20:23:31 2003 Return-Path: Delivered-To: cvs-src@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 99F9116A4C0 for ; Tue, 7 Oct 2003 20:23:31 -0700 (PDT) Received: from smtp.mho.com (smtp.mho.net [64.58.4.6]) by mx1.FreeBSD.org (Postfix) with SMTP id 8578F43FE5 for ; Tue, 7 Oct 2003 20:23:28 -0700 (PDT) (envelope-from scottl@freebsd.org) Received: (qmail 94371 invoked by uid 1002); 8 Oct 2003 03:23:25 -0000 Received: from unknown (HELO freebsd.org) (64.58.1.252) by smtp.mho.net with SMTP; 8 Oct 2003 03:23:25 -0000 Message-ID: <3F83832B.407@freebsd.org> Date: Tue, 07 Oct 2003 21:23:23 -0600 From: Scott Long User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.3) Gecko/20030425 X-Accept-Language: en-us, en MIME-Version: 1.0 To: David Rhodus References: <4906E41E-F938-11D7-B905-000A959B213E@catpa.com> In-Reply-To: <4906E41E-F938-11D7-B905-000A959B213E@catpa.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit cc: "Jacques A. Vidrine" cc: cvs-src@FreeBSD.org cc: src-committers@FreeBSD.org cc: cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/i386/i386 pmap.c X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 Oct 2003 03:23:31 -0000 David Rhodus wrote: > > On Tuesday, October 7, 2003, at 08:53 AM, Jacques A. Vidrine wrote: > >> On Tue, Oct 07, 2003 at 05:34:37AM -0700, Jacques A. Vidrine wrote: >> >>> nectar 2003/10/07 05:34:37 PDT >>> >>> FreeBSD src repository >>> >>> Modified files: (Branch: RELENG_4) >>> sys/i386/i386 pmap.c >>> Log: >>> Disable PSE at boot time for Pentium 4 processors. On many such CPUs, >>> data corruption will result otherwise. It seems that the bug is >>> aggravated by recent work related to PAE. >>> >>> This change was originally based on rev 1.386, but now the test for >>> CPU type is correct and the display of the warning is postponed until >>> we have initialized the kernel message buffer (e.g. for dmesg). >>> >>> peter@ believes that only certain revisions of the Pentium 4 processor >>> are affected. However, we are unsure which so we choose to be safe by >>> disabling PSE on all Pentium 4s. >>> >>> The test can be disabled entirely with NO_PSE_HACK. >>> >>> Approved by: re >>> >>> Revision Changes Path >>> 1.250.2.22 +34 -0 src/sys/i386/i386/pmap.c >> >> >> The symptoms from this bug that I experienced on an ``Intel(R) >> Celeron(R) CPU 2.00GHz'' system were SIGBUS and SIGSEGV during `make >> buildworld'. > > > Interesting, I was just typing a message to ask if we needed to look at > applying bmilekic's work to RELENG_4. Is that being looked at as a > more elegant method rather than leaving PSE turned off. > > -DR > > It might indeed be interesting to backport Bosko's work to 4.x. However, we are too close to the 4.9 release to do it now. Jacques' work is recognised as a band-aid for now. Scott