From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bartlomiej Zolnierkiewicz Subject: Re: [PATCH 1/3] Make the IDE DMA timeout modifiable Date: Sat, 16 Jun 2007 01:23:55 +0200 Message-ID: <200706160123.55636.bzolnier@gmail.com> References: <20070221011922.GA1777@freefall.freebsd.org> <200702210342.20775.bzolnier@gmail.com> <466EEFD6.9030001@ru.mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from ug-out-1314.google.com ([66.249.92.168]:64985 "EHLO ug-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757670AbXFOX0y (ORCPT ); Fri, 15 Jun 2007 19:26:54 -0400 Received: by ug-out-1314.google.com with SMTP id j3so964359ugf for ; Fri, 15 Jun 2007 16:26:53 -0700 (PDT) In-Reply-To: <466EEFD6.9030001@ru.mvista.com> Content-Disposition: inline Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Sergei Shtylyov Cc: Suleiman Souhlal , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org On Tuesday 12 June 2007, Sergei Shtylyov wrote: > Bartlomiej Zolnierkiewicz wrote: > >>On Feb 20, 2007, at 5:44 PM, Bartlomiej Zolnierkiewicz wrote: > > >>>On Wednesday 21 February 2007 02:19, Suleiman Souhlal wrote: > > >>>>It can be changed via /proc/ide/hd?/settings. > > >>>Why do we need to change IDE DMA timeout dynamically? > > >>I've used it to test error recovery (for example). > > > Seems quite useable for developers but I would prefer not to > > expose it in production kernels for end users. > > It seems that I have counter example of a customer asking if this timeout > can be done configurable. :-) May I ask what was the rationale for this request? I have no strong feelings about adding this /proc/ide/ setting but I worry that it could be (mis)used just to (unreliably) work-around problems... > BTW, why the timeout is so damn long? 2*WAIT_CMD is 20 secs, and if DMA is > not complete or interrupt pending, it may wait 10 more secs... I really don't remember... :) Maybe Mark or Alan could help with figuring this out. Thanks, Bart