Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261532AbVA2TKy (ORCPT ); Sat, 29 Jan 2005 14:10:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261531AbVA2TJC (ORCPT ); Sat, 29 Jan 2005 14:09:02 -0500 Received: from twilight.ucw.cz ([81.30.235.3]:59342 "EHLO suse.cz") by vger.kernel.org with ESMTP id S261533AbVA2TIK (ORCPT ); Sat, 29 Jan 2005 14:08:10 -0500 Date: Sat, 29 Jan 2005 12:25:10 +0100 From: Vojtech Pavlik To: Al Viro Cc: Roman Zippel , Andries Brouwer , linux-kernel@vger.kernel.org Subject: Re: Possible bug in keyboard.c (2.6.10) Message-ID: <20050129112510.GB2268@ucw.cz> References: <20050127125637.GA6010@pclin040.win.tue.nl> <20050128105937.GA5963@ucw.cz> <20050129045055.GS8859@parcelfarce.linux.theplanet.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050129045055.GS8859@parcelfarce.linux.theplanet.co.uk> User-Agent: Mutt/1.5.6i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1787 Lines: 44 On Sat, Jan 29, 2005 at 04:50:55AM +0000, Al Viro wrote: > > I'm very sorry about the locking, but the thing grew up in times of > > kernel 2.0, which didn't require any locking. There are a few possible > > Incorrect. You have blocking allocations in critical areas and they > required locking all way back. Ok. I see a problem where input_register_device() calls input handler connect methods, which do kmalloc(). This would be bad even on 2.0. Anything else? I believe the ->open()/->release() methods are still protected. > > races with device registration/unregistration, and it's on my list to > > fix that, however under normal operation there shouldn't be any need for > > locks, as there are no complex structures built that'd become > > inconsistent. > > Um-hm... Vojtech, meet USB mouse; USB mouse, meet Vojtech. Now watch > a disconnect and reconnect happening when luser suddenly gets overexcited > and jerks the wrong hand a bit too hard while browsing the most profitable > sort of website... I know. As I said, this is a problem I know about, and will be fixed. I was mainly interested whether anyone sees further problems in scenarios which don't include device addition/removal. We already fixed this in serio, and input and gameport are next in the list. > > If you find scenarios which will lead to trouble in the event delivery > > system, please tell me, and I'll try to fix that as soon as possible. > > See above. Devices appearing and disappearing *are* normal. -- Vojtech Pavlik SuSE Labs, SuSE CR - 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/