Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261712AbVBEBSo (ORCPT ); Fri, 4 Feb 2005 20:18:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263369AbVBEBKs (ORCPT ); Fri, 4 Feb 2005 20:10:48 -0500 Received: from mail.gmx.net ([213.165.64.20]:51153 "HELO mail.gmx.net") by vger.kernel.org with SMTP id S265016AbVBEBHX (ORCPT ); Fri, 4 Feb 2005 20:07:23 -0500 X-Authenticated: #26200865 Message-ID: <42041C6D.4000905@gmx.net> Date: Sat, 05 Feb 2005 02:07:57 +0100 From: Carl-Daniel Hailfinger User-Agent: Mozilla/5.0 (X11; U; Linux i686; de-AT; rv:1.7.2) Gecko/20040906 X-Accept-Language: de, en MIME-Version: 1.0 To: James Simmons CC: Pavel Machek , Jon Smirl , ncunningham@linuxmail.org, ACPI List , Linux Kernel Mailing List , Matthew Garrett Subject: Re: [RFC] Reliable video POSTing on resume References: <20050122134205.GA9354@wsc-gmbh.de> <4201825B.2090703@gmx.net> <420217DB.709@gmx.net> <4202A972.1070003@gmx.net> <20050203225410.GB1110@elf.ucw.cz> <1107474198.5727.9.camel@desktop.cunninghams> <4202DF7B.2000506@gmx.net> <9e47339105020321031ccaabb@mail.gmail.com> <420367CF.7060206@gmx.net> <20050204163019.GC1290@elf.ucw.cz> In-Reply-To: X-Enigmail-Version: 0.86.0.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1433 Lines: 31 James Simmons schrieb: >>>int video_helper(struct video_actions *what_to_do) >> >>I do not know, synchronously executing userland code from kernel seems >>like wrong thing to do. > > I'm not a fan for this either. The good news is most graphics cards don't > require these tricks. The only ones that do are the ix86 cards. The real > solution would be if the hradware vendors open the parts of the spec to do > what we need. Many of the older cards could be supported in this way if we > talk to the vendors. They shouldn't care if the specs are released anymore. > The problem would be the latest Radeon card and NVIDIA cards which > unfortunely are the most common cards for x86 platforms ;-( Well, either you call userspace synchronously or you crash on resume. I know what I prefer. And this synchronous call isn't so bad because it comes with a timeout. So whatever the userspace program does, after two seconds the kernel will continue unaffected. Once you execute the code asynchronously, you get nondeterministic behaviour. That's sure fun for filling up your random pool, but I wouldn't trust my data to such a system. Regards, Carl-Daniel -- http://www.hailfinger.org/ - 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/