From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga03.intel.com ([143.182.124.21]) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UG5PP-0006nE-Uo for linux-mtd@lists.infradead.org; Thu, 14 Mar 2013 10:29:16 +0000 Message-ID: <1363257009.11441.97.camel@sauron.fi.intel.com> Subject: Re: MTD : Kernel oops when remounting ubifs as read/write From: Artem Bityutskiy To: Mark Jackson Date: Thu, 14 Mar 2013 12:30:09 +0200 In-Reply-To: <51419E3A.8030007@mimc.co.uk> References: <5134CEF9.5070502@mimc.co.uk> <1363087506.3348.62.camel@sauron.fi.intel.com> <51405F3A.3090901@mimc.co.uk> <1363252425.11441.94.camel@sauron.fi.intel.com> <51419E3A.8030007@mimc.co.uk> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Cc: "linux-omap@vger.kernel.org" , "linux-mtd@lists.infradead.org" , lkml , adrian.hunter@intel.com Reply-To: dedekind1@gmail.com List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2013-03-14 at 09:54 +0000, Mark Jackson wrote: > On 14/03/13 09:13, Artem Bityutskiy wrote: > > On Wed, 2013-03-13 at 11:12 +0000, Mark Jackson wrote: > >> Sorry ... this just locks up the unit. > > > > OK, I've reproduced the issue with 3.9-rc2 in nandsim, see the details > > below. The patch I proposed did not get the error path correctly, but it > > does fix the issue. > > > > I think what you treat as "lockup" is the fixup process. UBIFS basically > > reads the entire UBI volume and writes it back. And it uses the atomic > > change UBI service, which means it also calculates CRC of everything it > > writes. And this all just takes a lot of time. This has to be done only > > once on the first mount. > > Okay ... I've retried, but how long is "a lot of time" ? > > I've waited 15 minutes and still nothing. > > And I can see that there's no activity on the NAND chip select !?! > > I'll put some debug info into the fixup routines to see if I can trace what's going on. Just to make sure - try this last patch I sent. I did test it with nandsim at least, and I am sure it works. I did not test at all the first one. And yes, debug messages would be useful, just do not forget to add the 'ignore_loglevel' kernel boot option, otherwise you won't see the messages on your console, since they are of KERN_DEBUG level. You may have other issues which cause lockup, e.g., in driver level. It makes sense to validate your flash with MTD test modules. -- Best Regards, Artem Bityutskiy