From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: [Bug #14388] keyboard under X with 2.6.31 Date: Tue, 13 Oct 2009 18:12:12 -0700 (PDT) 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> Mime-Version: 1.0 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: TEXT/PLAIN; charset="iso-8859-1" To: =?ISO-8859-15?Q?Fr=E9d=E9ric_L=2E_W=2E_Meunier?= Cc: 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 On Tue, 13 Oct 2009, Fr=E9d=E9ric L. W. Meunier wrote: >=20 > For now (more than 3h), it isn't doing any harm. And no keyboard lock= ups. I think it was Boyan who said he could trigger it "easily", and everybo= dy=20 else had a hard time to reproduce the problem, so I'll consider your "g= ood=20 for 3h" to not really be a confirmation either way. But at least it's n= ot=20 totally broken. > BTW, the old version of the patch was funny. It booted, but at the lo= gin > prompt I could only enter the first letter. Yeah, each time somebody read from a tty, the reading would also get ri= d=20 of all the buffers, but would leave buf.tail set to the last one (that = had=20 been freed).=20 Which then resulted in all subsequent IO going to that tail buffer, but= =20 nobody ever seeing it, because 'head' was NULL, and would stay that way= as=20 long as 'tail' existed (which it would until the tty was flushed, which= it=20 would never be). So you'd only ever see the first read (which could obviously be more th= an=20 one character, but you'd have to type REALLY FAST to get there ;^) Linus