From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pv0-f179.google.com (mail-pv0-f179.google.com [74.125.83.179]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 3C1D8B6F88 for ; Thu, 23 Jun 2011 18:30:45 +1000 (EST) Received: by pvg18 with SMTP id 18so1065083pvg.38 for ; Thu, 23 Jun 2011 01:30:41 -0700 (PDT) Subject: RE: NAND BBT corruption on MPC83xx From: Artem Bityutskiy To: Atlant Schmidt Date: Thu, 23 Jun 2011 11:31:25 +0300 In-Reply-To: <0A40042D85E7C84DB443060EC44B3FD32A7208F91B@dekaexchange07.deka.local> References: <20110617163442.204348a0@schlenkerla.am.freescale.net> <0A40042D85E7C84DB443060EC44B3FD32A7208F91B@dekaexchange07.deka.local> Content-Type: text/plain; charset="UTF-8" Message-ID: <1308817889.18119.98.camel@sauron> Mime-Version: 1.0 Cc: Scott Wood , "linuxppc-dev@lists.ozlabs.org" , "linux-mtd@lists.infradead.org" , "Matthew L. Creech" , 'Mike Hench' Reply-To: dedekind1@gmail.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, 2011-06-20 at 07:22 -0400, Atlant Schmidt wrote: > > As far as I know (and I'm sure the list will correct > me if I'm wrong! ;-) ), neither UBI nor UBIFS nor any > Linux layer provides this routine scrubbing; you have > to code it up yourself, probably by accessing the > device at the UBI (underlying block device/LEB) layer. UBI will scrub all LEBs with bit-flips once they are read. But if you have bit-flips in an LEB and it is never read, it will never be scrubbed. And erasures of the neighboring PEBs may turn bit-flips into hard errors. To force scrubbing, the easies way is to just read all volumes, like dd if=/dev/ubi0_i of=/dev/null bs=4096 for each i. -- Best Regards, Artem Bityutskiy