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From: Brian Norris <computersforpeace@gmail.com>
To: <linux-mtd@lists.infradead.org>
Cc: Brian Norris <computersforpeace@gmail.com>,
	David Woodhouse <dwmw2@infradead.org>,
	Artem Bityutskiy <dedekind1@gmail.com>
Subject: [PATCH mtd-www 4/4] faq: ubi: note that CONFIG_MTD_NAND_VERIFY_WRITE is dead
Date: Fri, 19 Dec 2014 18:38:26 -0800	[thread overview]
Message-ID: <1419043106-16453-4-git-send-email-computersforpeace@gmail.com> (raw)
In-Reply-To: <1419043106-16453-1-git-send-email-computersforpeace@gmail.com>

RIP.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
---
 faq/ubi.xml | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/faq/ubi.xml b/faq/ubi.xml
index 9b2165def9c3..f8c40f64044d 100644
--- a/faq/ubi.xml
+++ b/faq/ubi.xml
@@ -567,9 +567,27 @@ ubi.mtd=0,2048
 
 <p>If you have a 2048 bytes per NAND page device, and have
 <code>CONFIG_MTD_NAND_VERIFY_WRITE</code> enabled in your kernel, you will need
-to turn it off. The code does not currently (as of 2.6.26) perform verification
+to turn it off. The code did not currently (as of 2.6.26) perform verification
 of sub-page writes correctly. As UBI is one of the few users of sub-page
-writes, not much else seems to be affected by this bug.</p>
+writes, not much else seemed to be affected by this bug. In Linux 3.7,
+<code>CONFIG_MTD_NAND_VERIFY_WRITE</code> was removed:
+
+<pre>
+commit 657f28f8811c92724db10d18bbbec70d540147d6
+Date:   Tue Aug 14 22:38:45 2012 -0400
+
+    mtd: kill MTD_NAND_VERIFY_WRITE
+
+    "Both UBI and JFFS2 are able to read verify what they wrote already.
+    There are also MTD tests which do this verification. So I think there
+    is no reason to keep this in the NAND layer, let alone wasting RAM in
+    the driver to support this feature. Besides, it does not work for sub-pages
+    and many drivers have it broken. It hurts more than it provides benefits."
+
+    So kill MTD_NAND_VERIFY_WRITE entirely.
+</pre>
+
+</p>
 
 
 
-- 
1.9.1

  parent reply	other threads:[~2014-12-20  2:39 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-20  2:38 [PATCH mtd-www 1/4] footer: drop 'Last updated' and other buggy footer notices Brian Norris
2014-12-20  2:38 ` [PATCH mtd-www 2/4] source: update git tree information Brian Norris
2014-12-20  2:38 ` [PATCH mtd-www 3/4] doc / faq: spelling, grammar, etc Brian Norris
2014-12-20  2:38 ` Brian Norris [this message]
2015-01-06  6:20 ` [PATCH mtd-www 1/4] footer: drop 'Last updated' and other buggy footer notices Brian Norris

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