From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.nokia.com ([192.100.122.230] helo=mgw-mx03.nokia.com) by bombadil.infradead.org with esmtps (Exim 4.69 #1 (Red Hat Linux)) id 1Ln52r-0002pP-NV for linux-mtd@lists.infradead.org; Fri, 27 Mar 2009 05:56:05 +0000 Subject: Re: [RFC/PATCH] flash_eraseall: extra care if NOR flash is not BIT_WRITEABLE From: Artem Bityutskiy To: Sebastian Andrzej Siewior In-Reply-To: <20090326154142.GA15963@Chamillionaire.breakpoint.cc> References: <1237848138-18157-1-git-send-email-sebastian@breakpoint.cc> <1237848138-18157-4-git-send-email-sebastian@breakpoint.cc> <1237874727.14602.95.camel@localhost.localdomain> <20090324085530.GA21444@Chamillionaire.breakpoint.cc> <1237962807.14602.99.camel@localhost.localdomain> <20090326134418.GB21993@shareable.org> <20090326154142.GA15963@Chamillionaire.breakpoint.cc> Content-Type: text/plain; charset="UTF-8" Date: Fri, 27 Mar 2009 07:55:32 +0200 Message-Id: <1238133332.3321.98.camel@localhost.localdomain> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Cc: linux-mtd@lists.infradead.org, Jamie Lokier Reply-To: dedekind@infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2009-03-26 at 16:41 +0100, Sebastian Andrzej Siewior wrote: > * Jamie Lokier | 2009-03-26 13:44:18 [+0000]: > > >Artem Bityutskiy wrote: > >> It sounds wrong to me to make flash_eraseall depend on how JFFS2 is > >> compiled... > > > >It sounds wrong to me as well. > > > >What if you're running flash_eraseall on one kernel - it might not > >even have JFFS2 - and then use the flash later with a different kernel > >with a different setting. > > I'm sorry. That is actually my point. The layout of the cleanmarker > (which are used only by JFFS2) depends on a specific kernel switch in > case of NOR flash which is not BIT_WRITEABLE and userland can't know > that. > I've sent a patch to remove the -j option because the generated > cleanmaker *may* be wrong. Artem replied that he would like to see this > fixed. > So here is an attempt to fix this: black listed ubi & data flash but I > dunno how fix the NOR case where does not have BIT_WRITEABLE bit. A > commandline switch for those who know what they do? > Why don't rip out -j and let the kernel create clean marker if it > needs it? I looked into your patch closer, and there is no such dependency actually. Now it looks fine for me. I can apply them if there are not complaints. But how you have tested them? I would not want to break 'flash_eraseall' once again :-) -- Best regards, Artem Bityutskiy (Битюцкий Артём)