From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932250AbWAPIV5 (ORCPT ); Mon, 16 Jan 2006 03:21:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932249AbWAPIV5 (ORCPT ); Mon, 16 Jan 2006 03:21:57 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:21385 "EHLO mx3.mail.elte.hu") by vger.kernel.org with ESMTP id S932247AbWAPIV4 (ORCPT ); Mon, 16 Jan 2006 03:21:56 -0500 Date: Mon, 16 Jan 2006 09:21:59 +0100 From: Ingo Molnar To: Andrew Morton Cc: "Rafael J. Wysocki" , linux-kernel@vger.kernel.org, greg@kroah.com, zaitcev@redhat.com Subject: Re: 2.6.15-mm4: sem2mutex problem in USB OHCI Message-ID: <20060116082159.GA9744@elte.hu> References: <200601150058.58518.rjw@sisk.pl> <20060114160526.228da734.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060114160526.228da734.akpm@osdl.org> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: 0.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=0.0 required=5.9 tests=AWL autolearn=no SpamAssassin version=3.0.3 0.0 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 * Andrew Morton wrote: > > Badness in __mutex_trylock_slowpath at kernel/mutex.c:281 > > > > Call Trace: {mutex_trylock+141} > > > > {:ohci_hcd:ohci_hub_status_data+480} > > {rh_timer_func+0} {usb_hcd_poll_rh_status+67} > > {rh_timer_func+0} {rh_timer_func+9} > > {run_timer_softirq+396} > err, taking a mutex from softirq context. btw., i'm wondering how the down_trylock() can be correct code: what guarantees progress if the trylock happens to fail all the time? (or just happens to fail frequently, due to some other, unrelated dev->mutex workload) Shouldnt this code use some other solution to process these timed events more robustly? Ingo