Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268447AbUI2PNt (ORCPT ); Wed, 29 Sep 2004 11:13:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268589AbUI2OxJ (ORCPT ); Wed, 29 Sep 2004 10:53:09 -0400 Received: from rrcs-24-227-247-8.sw.biz.rr.com ([24.227.247.8]:3042 "EHLO emachine.austin.ammasso.com") by vger.kernel.org with ESMTP id S268527AbUI2Osy (ORCPT ); Wed, 29 Sep 2004 10:48:54 -0400 Message-ID: <415ACACE.1020008@ammasso.com> Date: Wed, 29 Sep 2004 09:46:38 -0500 From: Timur Tabi Organization: Ammasso User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.2) Gecko/20040803 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Dave Hansen CC: Christoph Hellwig , linux-mm , Linux Kernel Mailing List , kernelnewbies@nl.linux.org Subject: Re: get_user_pages() still broken in 2.6 References: <4159E85A.6080806@ammasso.com> <20040929000325.A6758@infradead.org> <1096413678.16198.16.camel@localhost> In-Reply-To: <1096413678.16198.16.camel@localhost> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 871 Lines: 25 Dave Hansen wrote: > You probably want mlock(2) to keep the kernel from messing with the ptes > at all. mlock() can only be called via sys_mlock(), which is a user-space call. Not only that, but only root can call sys_mlock(). This is not compatible with our needs. > But, you should probably really be thinking about why you're > accessing the page tables at all. I count *ONE* instance in drivers/ > where page tables are accessed directly. I access PTEs to get the physical addresses of a user-space buffer, so that we can DMA to/from it directly. -- Timur Tabi Staff Software Engineer timur.tabi@ammasso.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/