Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932688Ab2HPOcB (ORCPT ); Thu, 16 Aug 2012 10:32:01 -0400 Received: from mail-lb0-f174.google.com ([209.85.217.174]:52184 "EHLO mail-lb0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964799Ab2HPObr (ORCPT ); Thu, 16 Aug 2012 10:31:47 -0400 MIME-Version: 1.0 In-Reply-To: <20120816165027.6520c4f4@pixies.home.jungo.com> References: <1341937423-16516-1-git-send-email-richard.genoud@gmail.com> <1341937423-16516-5-git-send-email-richard.genoud@gmail.com> <20120816115713.726da8f2@pixies.home.jungo.com> <1345123718.3393.235.camel@sauron.fi.intel.com> <20120816165027.6520c4f4@pixies.home.jungo.com> From: Richard Genoud Date: Thu, 16 Aug 2012 16:30:59 +0200 Message-ID: Subject: Re: [PATCH 4/4] UBI: replace MTD_UBI_BEB_LIMIT with user-space parameter To: Shmulik Ladkani Cc: dedekind1@gmail.com, linux-mtd@lists.infradead.org, David Woodhouse , linux-kernel@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2170 Lines: 51 2012/8/16 Shmulik Ladkani : > On Thu, 16 Aug 2012 16:28:38 +0300 Artem Bityutskiy wrote: >> On Thu, 2012-08-16 at 11:57 +0300, Shmulik Ladkani wrote: >> > >> > For the simplest systems (those having one ubi device) that need a >> > limit >> > *other* than the default (20 per 1024), they can simply set the config >> > to their chosen value, as they were used to. >> > >> > With you approach, these system MUST pass the limit parameter via the >> > ioctl / module-parameter. >> >> Yeah, when you change the default, you usually need to do an extra step. >> It does not feel too bad, and I would not keep additional configuration >> option for a hypothetical user. If someone suffers, we can add an option >> to change the default. But I'd start without it. So, I think it is OK to >> remove this. > > Yes, but the main drawback I was referring to is those platforms already > setting MTD_UBI_BEB_RESERVE other than the default, by means of kernel > configuration. > (there's one platform known to do so in its defconfig, that's > sam9_l9260_defconfig, which uses 3% instead of the "standard" 2%). I found the board: https://www.olimex.com/dev/sam9-L9260.html and the nand datasheet: http://www.rockbox.org/wiki/pub/Main/LyrePrototype/K9xxG08UXM.pdf page 11, we can see that the max_bad_bebper1024 is 25 (100 for 4096) > These platforms must now change their usermode code to either pass a > module parameter during the insmod or change their attach ioctl of > their application. > > We force these systems to change their usermode because we changed ubi's > default BEB limit to be 20/1024 _hardcoded_ (instead of kernel > configurable as previously was). > > Is this ok? well, I don't know, Artem, you're the maintainer :) I made a quick patch on this, if you decide to apply it. Richard -- for me, ck means con kolivas and not calvin klein... does it mean I'm a geek ? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/