From owner-cvs-src@FreeBSD.ORG Mon Aug 8 20:02:23 2005 Return-Path: X-Original-To: cvs-src@FreeBSD.org 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 7E0BF16A41F; Mon, 8 Aug 2005 20:02:23 +0000 (GMT) (envelope-from nate@root.org) Received: from www.cryptography.com (li-22.members.linode.com [64.5.53.22]) by mx1.FreeBSD.org (Postfix) with ESMTP id 4C4A243D73; Mon, 8 Aug 2005 20:02:16 +0000 (GMT) (envelope-from nate@root.org) Received: from [10.0.5.50] (adsl-64-171-187-230.dsl.snfc21.pacbell.net [64.171.187.230]) by www.cryptography.com (8.12.8/8.12.8) with ESMTP id j78K2Go5026386 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Mon, 8 Aug 2005 13:02:17 -0700 Message-ID: <42F7BA45.4040700@root.org> Date: Mon, 08 Aug 2005 13:02:13 -0700 From: Nate Lawson User-Agent: Mozilla Thunderbird 1.0.6 (Windows/20050716) X-Accept-Language: en-us, en MIME-Version: 1.0 To: csjp@FreeBSD.org References: <200508081956.j78Jui1l095716@gw.catspoiler.org> In-Reply-To: <200508081956.j78Jui1l095716@gw.catspoiler.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: cvs-src@FreeBSD.org, Don Lewis , src-committers@FreeBSD.org, cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/kern kern_sysctl.c X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.5 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: Mon, 08 Aug 2005 20:02:23 -0000 Don Lewis wrote: > On 8 Aug, Christian S.J. Peron wrote: >>csjp 2005-08-08 18:54:35 UTC >> >> FreeBSD src repository >> >> Modified files: >> sys/kern kern_sysctl.c >> Log: >> Check to see if we wired the user-supplied buffers in SYSCTL_OUT, if >> the buffer has not been wired and we are holding any non-sleep-able locks, >> drop a witness warning. If the buffer has not been wired, it is possible >> that the writing of the data can sleep, especially if the page is not in >> memory. This can result in a number of different locking issues, including >> dead locks. > > > Thanks. > > I think SYSCTL_IN() should also check for locks. We don't have a > function to wire the buffer in this direction. > One other thing: I don't think this should be MFCd before 6.0. It's possible that there are some drivers that violate this rule and having a release trigger panics is bad. This is the same reason we turn off INVARIANTS for releases. -- Nate