Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762654AbYCCK6r (ORCPT ); Mon, 3 Mar 2008 05:58:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761864AbYCCK62 (ORCPT ); Mon, 3 Mar 2008 05:58:28 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:43829 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762430AbYCCK61 (ORCPT ); Mon, 3 Mar 2008 05:58:27 -0500 Date: Mon, 3 Mar 2008 11:57:52 +0100 From: Ingo Molnar To: Pavel Roskin Cc: Linus Torvalds , Zan Lynx , linux-kernel , Jon Masters , Rusty Russell Subject: Re: [PATCH 2.6.25] module: allow ndiswrapper to use GPL-only symbols Message-ID: <20080303105752.GA23594@elte.hu> References: <20080229012012.ajlsk4pow8wkkgss@webmail.spamcop.net> <1204304352.6767.21.camel@localhost> <1204305609.21719.16.camel@dv> <1204313978.2316.8.camel@dv> <20080229211513.GI27212@elte.hu> <1204324265.2316.70.camel@dv> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1204324265.2316.70.camel@dv> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1113 Lines: 26 * Pavel Roskin wrote: > > btw., what are the technical reasons why ndiswrapper cannot be done > > in userspace, much like the (wildly successful) FUSE concept? > > ndiswrapper contains essentially two drivers in one - PCI and USB. > The PCI driver uses DMA, which should be a strong argument for keeping > it in the kernel. how exactly does it use DMA - how does it allocate the memory it later on DMAs into, and how does it typically program that DMA target - is there any control over that in the NDIS protocol - or will NDIS drivers just write random addresses to the mmio space and then the hardware does DMA to/from those addresses? [without the NDIS framework having any knowledge about the encoding of those bits?] on modern hardware it might even be possible to jail an ndiswrapper driver to its own pages via the IOMMU. Ingo -- 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/