Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268580AbUI2PlR (ORCPT ); Wed, 29 Sep 2004 11:41:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268652AbUI2PlR (ORCPT ); Wed, 29 Sep 2004 11:41:17 -0400 Received: from zero.aec.at ([193.170.194.10]:36877 "EHLO zero.aec.at") by vger.kernel.org with ESMTP id S268580AbUI2PlM (ORCPT ); Wed, 29 Sep 2004 11:41:12 -0400 To: Timur Tabi cc: linux-kernel@vger.kernel.org Subject: Re: get_user_pages() still broken in 2.6 References: <2JyXo-77W-19@gated-at.bofh.it> <2JzgH-7rT-11@gated-at.bofh.it> <2JOpu-1y1-21@gated-at.bofh.it> From: Andi Kleen Date: Wed, 29 Sep 2004 17:41:09 +0200 In-Reply-To: <2JOpu-1y1-21@gated-at.bofh.it> (Timur Tabi's message of "Wed, 29 Sep 2004 17:20:14 +0200") Message-ID: User-Agent: Gnus/5.110003 (No Gnus v0.3) Emacs/21.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 801 Lines: 21 Timur Tabi writes: > Christoph Hellwig wrote: > >> get_user_pages locks the page in memory. It doesn't do anything about ptes. > > I don't understand the difference. I thought a locked page is one > that stays in memory (i.e. isn't swapped out) and whose physical > address never changes. Is that wrong? All I need to do is keep a > page in memory at the same physical address until I'm done with it. After get_user_pages you don't need the page tables anymore. The struct page *s returned by it can be used for DMA. -Andi - 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/