Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755931AbYCMKMc (ORCPT ); Thu, 13 Mar 2008 06:12:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754881AbYCMKLg (ORCPT ); Thu, 13 Mar 2008 06:11:36 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:35234 "EHLO gprs189-60.eurotel.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754854AbYCMKLe (ORCPT ); Thu, 13 Mar 2008 06:11:34 -0400 Date: Thu, 13 Mar 2008 09:08:04 +0100 From: Pavel Machek To: dl9pf@gmx.de, kernel list , Andrew Morton , Trivial patch monkey Subject: document memmap option better and help people with bad memory Message-ID: <20080313080804.GA19808@elf.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3043 Lines: 92 Provide example for memmap exclude option (it is slightly strange an non-trivial) and provide nice small HOWTO for people with bad memory. Signed-off-by: Jan-Simon Moeller Signed-off-by: Pavel Machek --- commit ec630f2291d7a3a154e22fa54cd74e5f6aa47f9a tree 9cf33f9fcda3ea363061acebc971c37815f6c907 parent 456fc99ea933d38466ee25681908868cde3425c5 author Pavel Thu, 13 Mar 2008 09:06:15 +0100 committer Pavel Thu, 13 Mar 2008 09:06:15 +0100 Documentation/bad_memory.txt | 45 +++++++++++++++++++++++++++++++++++ Documentation/kernel-parameters.txt | 4 +++ 2 files changed, 49 insertions(+), 0 deletions(-) diff --git a/Documentation/bad_memory.txt b/Documentation/bad_memory.txt new file mode 100644 index 0000000..df84162 --- /dev/null +++ b/Documentation/bad_memory.txt @@ -0,0 +1,45 @@ +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=$
+ +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$0x18690000 + diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 533e67f..f25da88 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1131,6 +1131,10 @@ and is between 256 and 4096 characters. memmap=nn[KMG]$ss[KMG] [KNL,ACPI] Mark specific memory as reserved. Region of memory to be used, from ss to ss+nn. + Example: Exclude memory from 0x18690000-0x1869ffff + memmap=64K$0x18690000 + or + memmap=0x10000$0x18690000 meye.*= [HW] Set MotionEye Camera parameters See Documentation/video4linux/meye.txt. -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/