From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: http://bugzilla.kernel.org/show_bug.cgi?id=11742 Date: Mon, 20 Oct 2008 08:07:03 +0200 Message-ID: <20081020060703.GA4266@gollum.tnic> References: <20081018180747.GA29577@gollum.tnic> <20081020112039W.fujita.tomonori@lab.ntt.co.jp> Reply-To: petkovbb@gmail.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from fg-out-1718.google.com ([72.14.220.152]:33037 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750769AbYJTGHM (ORCPT ); Mon, 20 Oct 2008 02:07:12 -0400 Received: by fg-out-1718.google.com with SMTP id 19so1287774fgg.17 for ; Sun, 19 Oct 2008 23:07:10 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20081020112039W.fujita.tomonori@lab.ntt.co.jp> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: FUJITA Tomonori Cc: valerio.p@libero.it, linux-ide@vger.kernel.org On Mon, Oct 20, 2008 at 11:20:49AM +0900, FUJITA Tomonori wrote: > On Sat, 18 Oct 2008 20:07:47 +0200 > Borislav Petkov wrote: > > > would you please take a look at this bug caused by > > > > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff_plain;h=e5318b531b008c79d2a0c0df06a7b8628da38e2f > > Did he confirm that this patch causes this bug? > > But, yes, this patch might be the cause. > > Using the dma safe check for all the non fs commands is the right > thing. But blk_queue_update_dma_pad() has side effects. It might be > the cause (but I'm not sure about it since I don't know how the ide > code completes requests). Well, imho and judging from __ide_end_request(), which wraps around __blk_end_request(), it reenables dma for 3 times (3 being random magic) and after that remains in pio. -- Regards/Gruss, Boris.