From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262869AbVA2HPT (ORCPT ); Sat, 29 Jan 2005 02:15:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262870AbVA2HPT (ORCPT ); Sat, 29 Jan 2005 02:15:19 -0500 Received: from adsl-64-174-59-65.dsl.snfc21.pacbell.net ([64.174.59.65]:1228 "EHLO vpnmail.netd.com") by vger.kernel.org with ESMTP id S262869AbVA2HPP (ORCPT ); Sat, 29 Jan 2005 02:15:15 -0500 Date: Fri, 28 Jan 2005 20:23:55 -0800 From: Om To: Rock Gordon Cc: Jan Hudec , linux-kernel@vger.kernel.org, kernelnewbies@nl.linux.org, Bernd Petrovitsch Subject: Re: userspace vs. kernelspace address Message-ID: <20050129042355.GA5527@netd.com> Reply-To: Om References: <20050128075209.GA14153@vagabond> <20050128214051.34768.qmail@web41411.mail.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050128214051.34768.qmail@web41411.mail.yahoo.com> User-Agent: Mutt/1.4.1i X-Operating-System: Linux turyx 2.6.9-exp Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 28, 2005 at 01:40:51PM -0800, Rock Gordon wrote: > Hi everbody, > > Thanks for your replies. > > However I think my copy_to_user and copy_from_user are > failing since the kernel-mode thread is copying data > into another process's address space, and I am not > sure how to do this. Do the get_fs() and set_fs() > combinations let you do that? If not, then how do I do My idea is on kernel thread is limited. But I think it is not possible to any userspace address from any kernel thread because they do not have access to it. Their proc_struct->mm field is empty. I am not sure whether set_fs and get_fs help in this case. HTH, Om