Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760852AbZJNBWD (ORCPT ); Tue, 13 Oct 2009 21:22:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753504AbZJNBWC (ORCPT ); Tue, 13 Oct 2009 21:22:02 -0400 Received: from mail.lang.hm ([64.81.33.126]:37536 "EHLO bifrost.lang.hm" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753486AbZJNBWB (ORCPT ); Tue, 13 Oct 2009 21:22:01 -0400 Date: Tue, 13 Oct 2009 18:20:37 -0700 (PDT) From: david@lang.hm X-X-Sender: dlang@asgard.lang.hm To: Linus Torvalds cc: =?ISO-8859-15?Q?Fr=E9d=E9ric_L=2E_W=2E_Meunier?= , Boyan , "Justin P. Mattock" , Nix , Alan Cox , Paul Fulghum , "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List , Dmitry Torokhov , Ed Tomlinson , OGAWA Hirofumi Subject: Re: [Bug #14388] keyboard under X with 2.6.31 In-Reply-To: Message-ID: References: <56acieJJ2fF.A.nEB.Hzl0KB@chimera> <87ljjgfcbu.fsf@spindle.srvr.nix> <4AD3F769.5080405@gmail.com> <4AD437F9.9020708@yahoo.co.uk> <4AD4DE4C.4010402@yahoo.co.uk> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1525 Lines: 36 On Tue, 13 Oct 2009, Linus Torvalds wrote: > On Tue, 13 Oct 2009, Fr?d?ric L. W. Meunier wrote: >> >> For now (more than 3h), it isn't doing any harm. And no keyboard lockups. > > I think it was Boyan who said he could trigger it "easily", and everybody > else had a hard time to reproduce the problem, so I'll consider your "good > for 3h" to not really be a confirmation either way. But at least it's not > totally broken. > >> BTW, the old version of the patch was funny. It booted, but at the login >> prompt I could only enter the first letter. > > Yeah, each time somebody read from a tty, the reading would also get rid > of all the buffers, but would leave buf.tail set to the last one (that had > been freed). > > Which then resulted in all subsequent IO going to that tail buffer, but > nobody ever seeing it, because 'head' was NULL, and would stay that way as > long as 'tail' existed (which it would until the tty was flushed, which it > would never be). > > So you'd only ever see the first read (which could obviously be more than > one character, but you'd have to type REALLY FAST to get there ;^) Interesting, I had a hadful of times in the last several months where I ran into something like this, but switching virtual terminals cleared it up. David Lang -- 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/