Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964963AbWEaLze (ORCPT ); Wed, 31 May 2006 07:55:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932488AbWEaLzd (ORCPT ); Wed, 31 May 2006 07:55:33 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:40678 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S932479AbWEaLzd (ORCPT ); Wed, 31 May 2006 07:55:33 -0400 Date: Wed, 31 May 2006 13:55:45 +0200 From: Ingo Molnar To: Steven Rostedt Cc: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: 2.6.17-rc5-mm1 Message-ID: <20060531115545.GA4874@elte.hu> References: <20060530022925.8a67b613.akpm@osdl.org> <1149045448.28264.4.camel@localhost.localdomain> <20060530211442.a260a32e.akpm@osdl.org> <20060531063103.GC21779@elte.hu> <1149076243.28264.8.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1149076243.28264.8.camel@localhost.localdomain> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -3.1 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-3.1 required=5.9 tests=ALL_TRUSTED,AWL,BAYES_50 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts 0.0 BAYES_50 BODY: Bayesian spam probability is 40 to 60% [score: 0.5000] 0.2 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1082 Lines: 27 * Steven Rostedt wrote: > > > It does that because it knows it's about to spend a long time talking > > > with the mii registers and it doesn't want to do that with interrupts > > > disabled. > > > > i still consider it a 'quirky' locking construct, because disabling > > interrupts for a long time also disables all other devices sharing the > > same IRQ line - not nice. > > > > Also, this is a really hard case for lockdep to detect > > automatically. (fortunately it's also relatively rare) > > What's the standard way to teach lockdep about this? Not yet. One possibility would be to use existing locks and to get rid of the disable_irq(). One technique could be to disable the IRQ on the card (i think the code already does this), and then call synchronize_irq() instead of disable_irq(). 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/