Document hadling of bad memory

Pavel Machek
2008-11-26T16:13:54Z

Document how to deal with bad memory reported with memtest.

Signed-off-by: Pavel Machek <pavel@suse.cz>

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+March 2008
+Jan-Simon Moeller, dl9pf@gmx.de
+
+
+How to deal with bad memory e.g. reported by memtest86+ ?
+#########################################################
+
+There are three possibilities I know of:
+
+1) Reinsert/swap the memory modules
+
+2) Buy new modules (best!) or try to exchange the memory
+ if you have spare-parts
+
+3) Use BadRAM or memmap
+
+This Howto is about number 3) .
+
+
+BadRAM
+######
+BadRAM is the actively developed and available as kernel-patch
+here: http://rick.vanrein.org/linux/badram/
+
+For more details see the BadRAM documentation.
+
+memmap
+######
+
+memmap is already in the kernel and usable as kernel-parameter at
+boot-time. Its syntax is slightly strange and you may need to
+calculate the values by yourself!
+
+Syntax to exclude a memory area (see kernel-parameters.txt for details):
+memmap=<size>$
+
+Example: memtest86+ reported here errors at address 0x18691458, 0x18698424 and
+ some others. All had 0x1869xxxx in common, so I chose a pattern of
+ 0x18690000,0xffff0000.
+
+With the numbers of the example above:
+memmap=64K$0x18690000
+ or
+memmap=0x10000$0x18690000
+

--
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