From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752269Ab2LSSKo (ORCPT ); Wed, 19 Dec 2012 13:10:44 -0500 Received: from merlin.infradead.org ([205.233.59.134]:43981 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751180Ab2LSSKg (ORCPT ); Wed, 19 Dec 2012 13:10:36 -0500 Message-ID: <50D20316.7020205@kernel.dk> Date: Wed, 19 Dec 2012 19:10:30 +0100 From: Jens Axboe MIME-Version: 1.0 To: Linus Torvalds CC: Shaohua Li , Neil Brown , Ingo Molnar , "linux-kernel@vger.kernel.org" , Andrew Morton Subject: Re: [boot crash] Re: [GIT PULL[ block drivers bits for 3.8 References: <50CF89EB.2030109@kernel.dk> <20121218092554.GA3823@gmail.com> <50D056A5.3040501@kernel.dk> <50D1D373.5060301@kernel.dk> In-Reply-To: X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2012-12-19 17:29, Linus Torvalds wrote: >> Of course it's been tested. Granted it got moved over too late (as 1 of >> 2 that did), but I've run the branch on a multitude of systems. >> Apparently none of them hit the case of having a zero granularity >> reported, so never hit the bug. > > I presumably happens on pretty much anything that doesn't have > discard. Of course, I've personally gotten rid of any rotating devices > I have, but it still sounds like there's a big testing hole somewhere. It doesn't, though it seems so. Otherwise I definitely would have seen it. It only happens if discard max sectors is set, but alignment isn't. I suspect because that first divide is ordered after the !max_discard_sectors check. At least here. And I suspect we would have seen a lot more reports if it DID trigger on anything that didn't have discard :-) -- Jens Axboe