From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 759BAC43141 for ; Thu, 21 Jun 2018 20:00:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 37C2021D66 for ; Thu, 21 Jun 2018 20:00:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 37C2021D66 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754240AbeFUUAF (ORCPT ); Thu, 21 Jun 2018 16:00:05 -0400 Received: from mga07.intel.com ([134.134.136.100]:51390 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753906AbeFUUAE (ORCPT ); Thu, 21 Jun 2018 16:00:04 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Jun 2018 13:00:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,253,1526367600"; d="scan'208";a="61176979" Received: from agluck-desk.sc.intel.com (HELO agluck-desk) ([10.3.52.160]) by orsmga003.jf.intel.com with ESMTP; 21 Jun 2018 13:00:03 -0700 Date: Thu, 21 Jun 2018 13:00:03 -0700 From: "Luck, Tony" To: Borislav Petkov Cc: LKML Subject: Re: [PATCH] x86/mce: Do not overwrite MCi_STATUS in mce_no_way_out() Message-ID: <20180621200003.GA22562@agluck-desk> References: <20180621124020.6244-1-bp@alien8.de> <20180621181808.GA20097@agluck-desk> <20180621191710.GI12742@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180621191710.GI12742@zn.tnic> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 21, 2018 at 09:17:11PM +0200, Borislav Petkov wrote: > On Thu, Jun 21, 2018 at 11:18:09AM -0700, Luck, Tony wrote: > > Counter proposal. We don't need the temp mci_status because we exit the > > loop early. Nor the "ret" variable. > > > > > > How does this look? > > Yap, better. I'll test it later or tomorrow: > Or even better. Just adds the "mce_read_aux()" to check ADDRV and MISCV and populate more of the struct mce. -Tony diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index e4cf6ff1c2e1..5e64e973c02b 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -772,23 +772,24 @@ EXPORT_SYMBOL_GPL(machine_check_poll); static int mce_no_way_out(struct mce *m, char **msg, unsigned long *validp, struct pt_regs *regs) { - int i, ret = 0; + int i; char *tmp; for (i = 0; i < mca_cfg.banks; i++) { m->status = mce_rdmsrl(msr_ops.status(i)); - if (m->status & MCI_STATUS_VAL) { - __set_bit(i, validp); - if (quirk_no_way_out) - quirk_no_way_out(i, m, regs); - } + if (!(m->status & MCI_STATUS_VAL)) + continue; + __set_bit(i, validp); + if (quirk_no_way_out) + quirk_no_way_out(i, m, regs); if (mce_severity(m, mca_cfg.tolerant, &tmp, true) >= MCE_PANIC_SEVERITY) { + mce_read_aux(m, i); *msg = tmp; - ret = 1; + return 1; } } - return ret; + return 0; } /*