From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757618Ab2IDSy0 (ORCPT ); Tue, 4 Sep 2012 14:54:26 -0400 Received: from mx1.redhat.com ([209.132.183.28]:18521 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757538Ab2IDSyZ (ORCPT ); Tue, 4 Sep 2012 14:54:25 -0400 Date: Tue, 4 Sep 2012 21:55:41 +0300 From: "Michael S. Tsirkin" To: Sjur =?iso-8859-1?Q?Br=E6ndeland?= Cc: Amit Shah , linux-kernel@vger.kernel.org, Rusty Russell , Ohad Ben-Cohen , Linus Walleij , virtualization@lists.linux-foundation.org Subject: Re: [RFC 1/2] virtio_console: Add support for DMA memory allocation Message-ID: <20120904185541.GB3602@redhat.com> References: <1346680277-5887-1-git-send-email-sjur.brandeland@stericsson.com> <20120903143018.GA5353@redhat.com> <20120903202737.GD6181@redhat.com> <20120904135022.GI9805@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 04, 2012 at 06:58:47PM +0200, Sjur Brændeland wrote: > Hi Michael, > > > Exactly. Though if we just fail load it will be much less code. > > > > Generally, using a feature bit for this is a bit of a problem though: > > normally driver is expected to be able to simply ignore > > a feature bit. In this case driver is required to > > do something so a feature bit is not a good fit. > > I am not sure what the right thing to do is. > > I see - so in order to avoid the binding between driver and device > there are two options I guess. Either make virtio_dev_match() or > virtcons_probe() fail. Neither of them seems like the obvious choice. > > Maybe adding a check for VIRTIO_CONSOLE_F_DMA_MEM match > between device and driver in virtcons_probe() is the lesser evil? > > Regards, > Sjur A simplest thing to do is change dev id. rusty? -- MST