Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268458AbUI2OWz (ORCPT ); Wed, 29 Sep 2004 10:22:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268457AbUI2OTz (ORCPT ); Wed, 29 Sep 2004 10:19:55 -0400 Received: from imladris.demon.co.uk ([193.237.130.41]:37892 "EHLO phoenix.infradead.org") by vger.kernel.org with ESMTP id S268447AbUI2OQG (ORCPT ); Wed, 29 Sep 2004 10:16:06 -0400 Date: Wed, 29 Sep 2004 15:16:01 +0100 From: Christoph Hellwig To: Keith Whitwell Cc: Discuss issues related to the xorg tree , Christoph Hellwig , dri-devel , lkml Subject: Re: New DRM driver model - gets rid of DRM() macros! Message-ID: <20040929151601.A13135@infradead.org> Mail-Followup-To: Christoph Hellwig , Keith Whitwell , Discuss issues related to the xorg tree , dri-devel , lkml References: <9e4733910409280854651581e2@mail.gmail.com> <20040929133759.A11891@infradead.org> <415AB8B4.4090408@tungstengraphics.com> <20040929143129.A12651@infradead.org> <415ABA34.9080608@tungstengraphics.com> <415AC2B3.6070900@tungstengraphics.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <415AC2B3.6070900@tungstengraphics.com>; from keith@tungstengraphics.com on Wed, Sep 29, 2004 at 03:12:03PM +0100 X-SRS-Rewrite: SMTP reverse-path rewritten from by phoenix.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1224 Lines: 24 On Wed, Sep 29, 2004 at 03:12:03PM +0100, Keith Whitwell wrote: > Thinking about it, it may not have been a problem of crashing, but rather that > the behaviour visible from a program attempting to read (or poll) was > different with noop versions of these functions to NULL versions, and that was > causing problems. This is 18 months ago, so yes, I'm being vague. > > The X server does look at this file descriptor, which is where the problem > would have arisen, but only the gamma & maybe ffb drivers do anything with it. Indeed, for read you're returning 0 now instead of the -EINVAL from common code when no ->read is present. I'd say the current drm behaviour is a bug, but if X drivers rely on it. Similar in poll your return 0 now while the generic code return (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM) for fds without ->poll, and again I'd say current drm behaviour could be considered a bug. for ->flush there's no behaviour change of not supplying it. - 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/