[PATCH mtd-www 4/4] faq: ubi: note that CONFIG_MTD_NAND_VERIFY_WRITE is dead
Brian Norris
computersforpeace at gmail.com
Fri Dec 19 18:38:26 PST 2014
RIP.
Signed-off-by: Brian Norris <computersforpeace at 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
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