From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <1331644149.3595.48.camel@sauron.fi.intel.com> Subject: Re: [PATCH] mtd: cfi: Wait for Block Erase operation to finish From: Artem Bityutskiy To: Joakim Tjernlund Date: Tue, 13 Mar 2012 15:09:09 +0200 In-Reply-To: References: <1330697193.91058.YahooMailClassic@web29016.mail.ird.yahoo.com> <1331289909.22872.65.camel@sauron.fi.intel.com> <1331642936.3595.39.camel@sauron.fi.intel.com> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-UWT14OazFHWWtYbCkCPh" Mime-Version: 1.0 Cc: linux-mtd-bounces@lists.infradead.org, linux-mtd@lists.infradead.org, dwmw2@infradead.org, philipp.zabel@gmail.com, Paul Parsons Reply-To: dedekind1@gmail.com List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --=-UWT14OazFHWWtYbCkCPh Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, 2012-03-13 at 13:55 +0100, Joakim Tjernlund wrote: > > > > On Tue, 2012-03-13 at 09:27 +0100, Joakim Tjernlund wrote: > > > > > > > > On Fri, 2012-03-02 at 15:30 +0100, Joakim Tjernlund wrote: > > > > > yes, UBI probably has some different use. One seems that it keeps > > > > > erasing the > > > > > same block over and over again if the erase fails. JFFS2 doesn't = do > > > > > that since > > > > > you can't trust a block that is failing erase(how can you be sure= that > > > > > write will work?) > > > > > So, IMHO, UBIFS should reconsider this policy. > > > > > > > > The thread is very long and I would like save my time by not going > > > > through it. But if you could start a new thread and formulate the > > > > problem with UBI, I could think about it a bit. I am open to change > > > > policies if it is not too much work. Otherwise I am open to give h= ints > > > > and suggestions and accept patches which change the policy. :-) > > > > > > I just noted from one of the logs Paul sent, it LOOKED like UBI tried > > > to erase the same sector several times if erase failed, gave me the i= mpression > > > that UBI would try erasing a failing sector over and over again. > > > I think Paul will have to provide details if this is the case or not. > > > > Correct, UBI does retry erasing several times, see function > > 'do_sync_erase()' in drivers/mtd/ubi/io.c. Why would this be a problem? >=20 > How can you trust a sector that fails to erase several times and then sud= denly works ? It could be a transient error, some random noise in the line, some electrons did not want to move by an accident, something like this :-) But I guess it does not make much sense for erase and write. For read it does make sense to re-try. I am happy to accept a patch. --=20 Best Regards, Artem Bityutskiy --=-UWT14OazFHWWtYbCkCPh Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAABAgAGBQJPX0b1AAoJECmIfjd9wqK0amUP/1p5L3+MW7+8jOkhmNbHt1pH MxvWocqTLJ/CV1Y8wq8GrE75OBuFhDXiskrYuS9c8b4X3JCzHS25c5k9rzw1utL5 66PDHuC2X7ol2thcD2q2Q9Oae/N2A0r91hEVTBI71nzk1OTmGPBBR9BrjdQwFXSv QzqrKk0fj2kWUdcD8WJhBbUgehpvaNVbRAax+JoiIcE056ToxeHxLc/yIJ6mKyAz RaHjey/Z4OrsTQh5+WBQWz6s2dXTzjiltuep9pBun4kMdeTDArfB/SWQlAwhBfQx CktRxXXx+BS2Zp1I4rytsQgejWGQn9v8C58rLNh+D6VfRv81kcOo4tUd5UG/kUhk dw8x9ELM4Khph55Xe+OPHw4tjDVLRv2HCCPudcwWGJIpgoviPNav59wisgEtJDFJ tpcaXYw8k315+tl+fAZY9Hn7MECVGLfvmVkXP1yQB6onDW+9r8VhgczYvl81zqH9 ZpMi2kNk5R2nc4UEmZ+0ppBYxWYvJvFBpLI4XD709kIKPeakHvSEfFdb+H97o2wK Snu8wdE0Wg+eGXTAnRgi/lGTbm77mDJTOsZMNwlzyq7qknsZ3O7Q8i+T491gsJ43 U+5yUUIHaC/n/2QFPsCaaTww1R1Jyq+kNFUHlyjvLqXyjqYdC94krO9Wt9L6SRY4 xZIUVZuonz85irwxIME8 =EKZ6 -----END PGP SIGNATURE----- --=-UWT14OazFHWWtYbCkCPh--