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