From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1abPUF-0001at-5u for barebox@lists.infradead.org; Thu, 03 Mar 2016 09:23:59 +0000 Date: Thu, 3 Mar 2016 10:23:36 +0100 From: Sascha Hauer Message-ID: <20160303092336.GX9224@pengutronix.de> References: <3665455.GH0lG2JcVq@ws-stein> <9617410.tHQtcjn6HO@ws-stein> <20160303082856.GW9224@pengutronix.de> <2657168.Ls95HLtK4M@ws-stein> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <2657168.Ls95HLtK4M@ws-stein> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: UBIFS recovery fails in barebox while Linux suceeds To: Alexander Stein Cc: barebox@lists.infradead.org, Daniel =?iso-8859-15?Q?Kr=FCger?= On Thu, Mar 03, 2016 at 09:38:30AM +0100, Alexander Stein wrote: > On Thursday 03 March 2016 09:28:56, Sascha Hauer wrote: > > On Thu, Mar 03, 2016 at 08:16:13AM +0100, Alexander Stein wrote: > > > On Wednesday 02 March 2016 20:56:13, Sascha Hauer wrote: > > > > On Wed, Mar 02, 2016 at 05:19:08PM +0100, Alexander Stein wrote: > > > > > Hi, > > > > > > > > > > in case a UBIFS needs recovery (unclean write or whatever on NOR > > > > > flash) it is possible that barebox fails to do so while Linux suceeds. > > > > > The main cause, IMHO, is that Linux takes max_write_size into account > > > > > (starting with commit 2765df7da540687c4d57ca840182122f074c5b9c "UBIFS: > > > > > use max_write_size during recovery") while barebox doesn't. Apparently > > > > > is_last_write (fs/ubifs/recovery.c) results differently due to that > > > > > fact which explains why recovery progress differently. I don't know > > > > > which linux version the ubifs code in barebox is taken from but I > > > > > guess this needs to be updated. Are there any plans? > > > > > > > > The barebox UBIFS code is taken from U-Boot 2013.07 which is taken from > > > > Linux-2.6.29-rc6, so indeed the code is quite old. U-Boot has updated > > > > UBIFS support to Linux-4.2. The question is if we update UBIFS from > > > > U-Boot or directly from the Kernel, I have no idea which way is easier. > > > > > > I still wonder if this problem should have been avoided in the first > > > place. It seems like the change in the kernel is like chaning the > > > on-disk-format. > > > > BTW what happens after the failed recovery? Is the filesystem not > > readable? > > It is not even mounted, neither in barebox in current state, nor e.g. using mtdram in Linux with a different writebuf size. > Recovery fails so does mounting ubifs. Once recovery suceeded everybody is happy again. > BTW: mtdram in barebox would suffer the same problem, writebufsize is fixed 64. > > > > > > > > Currently there are no plans to update UBIFS, but of course you are > > > > invited to create them ;) > > > > > > I expected an answer like that ;-) I did a quick compare and there are > > > a lot of changes in barebox upon the code taken from u-boot. AFAICS > > > those are not documented :( > > > > I wouldn't say that. I just checked out barebox 551b412 (the initial > > ubifs commit) and U-Boot 2013.07 and copied over the ubifs files from > > U-Boot to barebox. The diff doesn't look too bad, it nearly only shows > > the changes necessary to adopt to the barebox filesystem layer. > > I assume fs/ubifs/ubifs.c can be left nearly unmodified. The rest is > > copying over the kernel files and boxing them through the compiler > > (which indeed might be a significant amount of work given the size of > > the code) > > Well, linux and u-boot, to some degree at least, IIRC gained support for fastmap, xattr and even optional atime support. Maybe it won't that easy anymore. Fastmap is a UBI feature, not a UBIFS feature. barebox supports that aswell. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox