From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751430AbeBWLJn (ORCPT ); Fri, 23 Feb 2018 06:09:43 -0500 Received: from mail.skyhub.de ([5.9.137.197]:35298 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750910AbeBWLJm (ORCPT ); Fri, 23 Feb 2018 06:09:42 -0500 Date: Fri, 23 Feb 2018 12:09:24 +0100 From: Borislav Petkov To: Anna Karbownik Cc: mchehab@kernel.org, linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org, dan.carpenter@oracle.com, tony.luck@intel.com, jim.m.snow@intel.com, qiuxu.zhuo@intel.com, lukasz.odzioba@intel.com, krzysztof.paliswiat@intel.com Subject: Re: [PATCH 1/1] EDAC, sb_edac: Fix out of bound write during DIMM configuration on KNL Message-ID: <20180223110924.GB4981@pd.tnic> References: <1519312693-4789-1-git-send-email-anna.karbownik@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1519312693-4789-1-git-send-email-anna.karbownik@intel.com> User-Agent: Mutt/1.9.3 (2018-01-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 22, 2018 at 04:18:13PM +0100, Anna Karbownik wrote: > From: akarbown > > In one of the previous patches we decreased NUM_CHANNELS from 8 to 4, but We say which patch it was. Anyway, corrected and applied the below, thanks. --- From: Anna Karbownik Date: Thu, 22 Feb 2018 16:18:13 +0100 Subject: [PATCH] EDAC, sb_edac: Fix out of bound writes during DIMM configuration on KNL Commit 3286d3eb906c ("EDAC, sb_edac: Drop NUM_CHANNELS from 8 back to 4") decreased NUM_CHANNELS from 8 to 4, but this is not enough for Knights Landing which supports up to 6 channels. This caused out-of-bounds writes to pvt->mirror_mode and pvt->tolm variables which don't pay critical role on KNL code path, so the memory corruption wasn't causing any visible driver failures. The easiest way of fixing it is to change NUM_CHANNELS to 6. Do that. An alternative solution would be to restructure the KNL part of the driver to 2MC/3channel representation. Reported-by: Dan Carpenter Signed-off-by: Anna Karbownik Cc: Mauro Carvalho Chehab Cc: Tony Luck Cc: jim.m.snow@intel.com Cc: krzysztof.paliswiat@intel.com Cc: lukasz.odzioba@intel.com Cc: qiuxu.zhuo@intel.com Cc: linux-edac Cc: Fixes: 3286d3eb906c ("EDAC, sb_edac: Drop NUM_CHANNELS from 8 back to 4") Link: http://lkml.kernel.org/r/1519312693-4789-1-git-send-email-anna.karbownik@intel.com [ Massage commit message. ] Signed-off-by: Borislav Petkov --- drivers/edac/sb_edac.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/edac/sb_edac.c b/drivers/edac/sb_edac.c index f34430f99fd8..872100215ca0 100644 --- a/drivers/edac/sb_edac.c +++ b/drivers/edac/sb_edac.c @@ -279,7 +279,7 @@ static const u32 correrrthrsld[] = { * sbridge structs */ -#define NUM_CHANNELS 4 /* Max channels per MC */ +#define NUM_CHANNELS 6 /* Max channels per MC */ #define MAX_DIMMS 3 /* Max DIMMS per channel */ #define KNL_MAX_CHAS 38 /* KNL max num. of Cache Home Agents */ #define KNL_MAX_CHANNELS 6 /* KNL max num. of PCI channels */ -- 2.13.0 -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.