From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756059Ab2DMTjO (ORCPT ); Fri, 13 Apr 2012 15:39:14 -0400 Received: from mail-iy0-f174.google.com ([209.85.210.174]:36094 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751765Ab2DMTjM (ORCPT ); Fri, 13 Apr 2012 15:39:12 -0400 Date: Fri, 13 Apr 2012 14:39:05 -0500 From: Jonathan Nieder To: Andrew Morton Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Ben Hutchings , Andreas Herrmann , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Subject: [PATCH resend] x86: memtest: WARN if bad RAM found Message-ID: <20120413193905.GD2387@burratino> References: <20120402150522.GA4980@burratino> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120402150522.GA4980@burratino> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ben Hutchings Date: Mon, 5 Dec 2011 04:00:58 +0000 Since this is not a particularly thorough test, if we find any bad bits of RAM then there is a fair chance that there are other bad bits we fail to detect. Warn so the TAINT_WARNING flag shows up in panic traces and other bug reports from users that enabled memtest and found bad RAM during bootup, to help people debugging to see that problems are potentially due to unreliable RAM. The warning text gives advice that can be used to make the warning go away using a more thorough test: Bad RAM detected. Use memtest86+ to perform a thorough test and the memmap= parameter to reserve the bad areas. In this way, this patch should make the lives of people helping to analyze bug reports from builds with CONFIG_MEMTEST enabled easier. [jn: more explanation of impact] Signed-off-by: Ben Hutchings Signed-off-by: Jonathan Nieder --- Hi again, The patch below last visited this list on 2 April, about a week and a half ago. No reply. The patch has been in Debian since last December. I like it. The patch is targetted at v3.5, so I would like to see it in linux-next so it can get more exposure. Comments? Thanks, Jonathan arch/x86/mm/memtest.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/mm/memtest.c b/arch/x86/mm/memtest.c index c80b9fb95734..38caeb44a218 100644 --- a/arch/x86/mm/memtest.c +++ b/arch/x86/mm/memtest.c @@ -30,6 +30,8 @@ static u64 patterns[] __initdata = { static void __init reserve_bad_mem(u64 pattern, u64 start_bad, u64 end_bad) { + WARN_ONCE(1, "Bad RAM detected. Use memtest86+ to perform a thorough test\n" + "and the memmap= parameter to reserve the bad areas."); printk(KERN_INFO " %016llx bad mem addr %010llx - %010llx reserved\n", (unsigned long long) pattern, (unsigned long long) start_bad, -- 1.7.10