From owner-freebsd-current@FreeBSD.ORG Sun Oct 1 20:48:27 2006 Return-Path: X-Original-To: current@freebsd.org Delivered-To: freebsd-current@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id E706216A403; Sun, 1 Oct 2006 20:48:27 +0000 (UTC) (envelope-from alc@cs.rice.edu) Received: from mail.cs.rice.edu (mail.cs.rice.edu [128.42.1.31]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8C4FA43D45; Sun, 1 Oct 2006 20:48:27 +0000 (GMT) (envelope-from alc@cs.rice.edu) Received: from mail.cs.rice.edu (localhost.localdomain [127.0.0.1]) by mail.cs.rice.edu (Postfix) with ESMTP id 4644A2C2C0B; Sun, 1 Oct 2006 15:48:27 -0500 (CDT) X-Virus-Scanned: by amavis-2.4.0 at mail.cs.rice.edu Received: from mail.cs.rice.edu ([127.0.0.1]) by mail.cs.rice.edu (mail.cs.rice.edu [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 2vvm67SSTDCl; Sun, 1 Oct 2006 15:48:26 -0500 (CDT) Received: from [216.63.78.18] (adsl-216-63-78-18.dsl.hstntx.swbell.net [216.63.78.18]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.cs.rice.edu (Postfix) with ESMTP id 908332C2C0A; Sun, 1 Oct 2006 15:48:26 -0500 (CDT) Message-ID: <4520299A.80102@cs.rice.edu> Date: Sun, 01 Oct 2006 15:48:26 -0500 From: Alan Cox User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.7.10) Gecko/20050817 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Martin Blapp References: <20060928195536.Y91466@godot.imp.ch> <20061001132422.O91466@godot.imp.ch> <45201C2B.7080706@cs.rice.edu> <20061001223622.R91466@godot.imp.ch> In-Reply-To: <20061001223622.R91466@godot.imp.ch> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: alc@freebsd.org, current@freebsd.org Subject: Re: CURRENT unusable again, too many panics X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 01 Oct 2006 20:48:28 -0000 Martin Blapp wrote: >> Can you tell me what if anything is printed with the attached patch >> applied? >> > > Hi, > >> MFC >> Correct a very old and very obscure bug: vmspace_fork() calls >> pmap_copy() if the mapping is VM_INHERIT_SHARE. Suppose the mapping >> is also wired. vmspace_fork() clears the wiring attributes in the vm >> map entry but pmap_copy() copies the PG_W attribute in the PTE. I >> don't think this is catastrophic. It blocks pmap_remove_pages() from >> destroying the mapping and corrupts the pmap's wiring count. > > > With or without this MFC applied ? > It won't matter. However, the patch will likely not apply cleanly with the above change backed out simply due to the context being different. Alan