From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753840Ab2LNLp4 (ORCPT ); Fri, 14 Dec 2012 06:45:56 -0500 Received: from mail-la0-f46.google.com ([209.85.215.46]:38693 "EHLO mail-la0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752282Ab2LNLpz (ORCPT ); Fri, 14 Dec 2012 06:45:55 -0500 Message-ID: <50CB116D.7050701@openvz.org> Date: Fri, 14 Dec 2012 15:45:49 +0400 From: Konstantin Khlebnikov User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.11) Gecko/20121123 Firefox/10.0.11 Iceape/2.7.11 MIME-Version: 1.0 To: Borislav Petkov , linux-kernel@vger.kernel.org, Jeff Garzik CC: Alan Cox Subject: Re: [PATCH] ata: uncomment ata_timing for XFER_PIO_SLOW References: <20121214110137.9155.68183.stgit@zurg> <20121214111351.GA7307@liondog.tnic> In-Reply-To: <20121214111351.GA7307@liondog.tnic> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Borislav Petkov wrote: > On Fri, Dec 14, 2012 at 03:01:37PM +0400, Konstantin Khlebnikov wrote: >> This patch uncomments ata timings for XFER_PIO_SLOW, >> otherwise ata_timing_find_mode() returns NULL and kernel crashes in >> pacpi_set_dmamode() after null-pointer dereference. >> >> The same problem was mentioned recently in debug patch v3.7-rc5-72-gcd705d5 >> ("libata debugging: Warn when unable to find timing descriptor based on xfer_mode") >> >> I'm not sure about this patch, because I have no idea what this XFER_PIO_SLOW > > No, this is already fixed by: > > > Btw, this patch will go to stable since I can't find it in 3.7, I'm > guessing Jeff will send it to Linus soonish since it is in his NEXT > branch. > > Until that happens, you could test 3.7 by cherrypicking the patch above > ontop of it or by simply applying it by hand since it is only two lines. > > Or, you could wait and test -rc1 when it comes out after the world ends :-). Ah, thanks. Sorry for noise. I'll check this again in current linux-next. > >> means and why this bug so rare (3 times during 4 days boot-reboot test) I caught >> this on completely ordinary PC with nvidia MCP61 chipset, sata hdd and ide dvd-rom. >> >> Signed-off-by: Konstantin Khlebnikov >> Signed-off-by: Borislav Petkov >> Signed-off-by: Jeff Garzik > > Btw, just FYI, this is not how S-o-b chaining works. Take a look > at for details on how it is done > correctly. ouch :facepalm: how I missed this... just copy-paste error. sorry again. > > HTH. >