Re: Document hadling of bad memory

Pavel Machek
2008-12-09T12:32:21Z

I cleaned the document up according to Randy (thanks!). I don't actually know
enough about DRAM error characcteristics, I guess'round the size of
bad region up to nearest 2^n makes sense.

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

diff --git a/Documentation/bad_memory.txt b/Documentation/bad_memory.txt
index df84162..a2a8703 100644
--- a/Documentation/bad_memory.txt
+++ b/Documentation/bad_memory.txt
@@ -14,12 +14,12 @@ There are three possibilities I know of:

3) Use BadRAM or memmap

-This Howto is about number 3) .
+This Howto is about number 3).

BadRAM
######
-BadRAM is the actively developed and available as kernel-patch
+BadRAM is the actively developed and available as a kernel patch
here: http://rick.vanrein.org/linux/badram/

For more details see the BadRAM documentation.
@@ -27,19 +27,20 @@ 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!
+memmap is already in the kernel and usable as a 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
+Example: memtest86+ reported errors at address 0x18691458, 0x18698424 and
some others. All had 0x1869xxxx in common, so I chose a pattern of
- 0x18690000,0xffff0000.
+ 0x18690000 and size of 0x10000. (Size needs to cover at least all
+ known bad places, and rounding to nearest power of 2 makes sense
+ 'just to be safe').

With the numbers of the example above:
memmap=64K$0x18690000
or
memmap=0x10000$0x18690000
-

--

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