From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751654AbaERQf3 (ORCPT ); Sun, 18 May 2014 12:35:29 -0400 Received: from mail.skyhub.de ([78.46.96.112]:45782 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751381AbaERQf2 (ORCPT ); Sun, 18 May 2014 12:35:28 -0400 Date: Sun, 18 May 2014 18:35:08 +0200 From: Borislav Petkov To: Chen Yucong Cc: tony.luck@intel.com, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org Subject: Re: [PATCH] x86/mce: Distirbute the clear operation of mces_seen to Per-CPU rather than only monarch CPU Message-ID: <20140518163508.GA8003@pd.tnic> References: <1400425504-8821-1-git-send-email-slaoub@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1400425504-8821-1-git-send-email-slaoub@gmail.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, May 18, 2014 at 11:05:04PM +0800, Chen Yucong wrote:a > mces_seen is a Per-CPU variable which should only be accessed by > Per-CPU as possible. So the clear operation of mces_seen should also > be lcoal to Per-CPU rather than monarch CPU. No, you need to do the cleaning in mce_reign because the monarch cpu has to run last after all other cpus have scanned their mce banks. > Meanwhile, there is also a potential risk that mces_seen will not > be be cleared if a timeout occors in mce_end for monarch CPU. As a > reuslt, the stale value of mces_seen will reappear on the next mce. If that happens, we have a bigger problem. Is that a real issue you're trying to address? -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --