From: "Bounine, Alexandre" Subject: RE: [PATCH v2 5/7] powerpc/85xx: Add MChk handler for SRIO port Date: Thu, 5 Aug 2010 11:17:58 -0700 Lines: 18 Message-ID: <0CE8B6BE3C4AD74AB97D9D29BD24E55201193609@CORPEXCH1.na.ads.idt.com> References: <20100308191005.GE4324@amak.tundra.com> <4381.1280815590@neuling.org> <0CE8B6BE3C4AD74AB97D9D29BD24E5520114309D@CORPEXCH1.na.ads.idt.com> <0CE8B6BE3C4AD74AB97D9D29BD24E552011430BC@CORPEXCH1.na.ads.idt.com> <26581.1280979260@neuling.org> <0CE8B6BE3C4AD74AB97D9D29BD24E552011935BD@CORPEXCH1.na.ads.idt.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Cc: "Michael Neuling" , "Timur Tabi" , "Alexandre Bounine" , , , , "Li Yang-R58472" To: "Kumar Gala" X-From: linux-kernel-owner@vger.kernel.org Thu Aug 05 20:18:33 2010 Return-path: Envelope-to: glk-linux-kernel-3@lo.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Oh51V-00075S-1W for glk-linux-kernel-3@lo.gmane.org; Thu, 05 Aug 2010 20:18:33 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934019Ab0HESSU (ORCPT ); Thu, 5 Aug 2010 14:18:20 -0400 Received: from mxout1.idt.com ([157.165.5.25]:47318 "EHLO mxout1.idt.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933252Ab0HESSS convert rfc822-to-8bit (ORCPT ); Thu, 5 Aug 2010 14:18:18 -0400 Received: from mail.idt.com (localhost [127.0.0.1]) by mxout1.idt.com (8.13.1/8.13.1) with ESMTP id o75II315017058; Thu, 5 Aug 2010 11:18:03 -0700 Received: from corpml1.corp.idt.com (corpml1.corp.idt.com [157.165.140.20]) by mail.idt.com (8.13.8/8.13.8) with ESMTP id o75II1Ek021771; Thu, 5 Aug 2010 11:18:01 -0700 (PDT) Received: from CORPEXCH1.na.ads.idt.com (localhost [127.0.0.1]) by corpml1.corp.idt.com (8.11.7p1+Sun/8.11.7) with ESMTP id o75II0M19896; Thu, 5 Aug 2010 11:18:00 -0700 (PDT) X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message In-Reply-To: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [PATCH v2 5/7] powerpc/85xx: Add MChk handler for SRIO port Thread-Index: Acs0x5rSJ4s7P9ssRjKYVWxFQe3GMgAARQEw X-Scanned-By: MIMEDefang 2.43 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Archived-At: > I'm looking at this now and wondering what we added the mcheck handler for in the first place and what > its trying to accomplish. > > - k This protects system from hanging if RIO link fails or enters error state. In some situations following maintenance read may initiate link recovery from error state. As it is now, MCheck mostly prevents system from hanging, but it also adds sense to return status of maintenance read routine. I am using return status in my new set of patches to check if RIO link is valid during error recovery. Alex.