From owner-cvs-all@FreeBSD.ORG Mon Feb 16 13:23:16 2004 Return-Path: Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6A7DC16A4CE; Mon, 16 Feb 2004 13:23:16 -0800 (PST) Received: from harmony.village.org (rover.bsdimp.com [204.144.255.66]) by mx1.FreeBSD.org (Postfix) with ESMTP id 08B8743D1F; Mon, 16 Feb 2004 13:23:16 -0800 (PST) (envelope-from imp@bsdimp.com) Received: from localhost (warner@rover2.village.org [10.0.0.1]) by harmony.village.org (8.12.10/8.12.9) with ESMTP id i1GLNEnJ003975; Mon, 16 Feb 2004 14:23:14 -0700 (MST) (envelope-from imp@bsdimp.com) Date: Mon, 16 Feb 2004 14:23:12 -0700 (MST) Message-Id: <20040216.142312.76327813.imp@bsdimp.com> To: scottl@FreeBSD.org From: "M. Warner Losh" In-Reply-To: <20040216120153.S80753@pooker.samsco.home> References: <20040216120153.S80753@pooker.samsco.home> X-Mailer: Mew version 3.3 on Emacs 21.3 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit cc: cvs-src@FreeBSD.org cc: src-committers@FreeBSD.org cc: rwatson@FreeBSD.org cc: cvs-all@FreeBSD.org cc: des@FreeBSD.org Subject: Re: cvs commit: src/sys/vm vm_kern.c X-BeenThere: cvs-all@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the entire tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 Feb 2004 21:23:16 -0000 In message: <20040216120153.S80753@pooker.samsco.home> Scott Long writes: : On Mon, 16 Feb 2004, Robert Watson wrote: : > : > On Mon, 16 Feb 2004, Dag-Erling Smorgrav wrote: : > : > > Log: : > > Don't panic if we fail to satisfy an M_WAITOK request; return 0 instead. : > > The calling code will either handle that gracefully or cause a page fault. : > : > Also, this turns an easily understood and widely documented kernel panic : > message into a page fault. Prior to this, users could google for the : > message and find documentation on increasing the size of the kernel : > address space. Now, it requires facility with the source code in order to : > figure out what it is going on (since the page fault trace won't include : > the memory allocation). : > : : Agreed on all points. I thought that there was along discussion on this : in the last 1-2 weeks and that all of these issues were brought up. : Please back this out, and lets focus on getting the sematics that you need : for procfs rather than just ruining the sematics for everything else. Please back this out. We worked for a long time to make M_WAITOK mean that the return value is never null. Warner