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=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 E8A15CA9EA0 for ; Fri, 25 Oct 2019 14:22:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B051B20684 for ; Fri, 25 Oct 2019 14:22:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="nPhjqJOR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733297AbfJYOWz (ORCPT ); Fri, 25 Oct 2019 10:22:55 -0400 Received: from mail.skyhub.de ([5.9.137.197]:54056 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730051AbfJYOWz (ORCPT ); Fri, 25 Oct 2019 10:22:55 -0400 Received: from zn.tnic (p200300EC2F0D3C00E44239D1C9BE3FA7.dip0.t-ipconnect.de [IPv6:2003:ec:2f0d:3c00:e442:39d1:c9be:3fa7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id D0D9F1EC0CD7; Fri, 25 Oct 2019 16:22:53 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1572013374; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=iLT7/FA+jxa/DCuxDSyuhoJdyith+QPQWFGJS46avAU=; b=nPhjqJORT9hY9M4rCp5ditj4nlo+4eHRIuR7edUUE44I9CJLWFxn04vyjHR1iD6I14oiAj 9bgh4p/sJX89DDRDTTzZZUxS25q3v4uQYIu6K5E6/RMeoFYUQdaNfkGdTtPr67BsIOmoyZ 1rqrlq5iZui5ZSENyS/8pxGA1KD4Tcc= Date: Fri, 25 Oct 2019 16:22:48 +0200 From: Borislav Petkov To: Sean Christopherson Cc: Tony Luck , Thomas Gleixner , Ingo Molnar , x86@kernel.org, "H. Peter Anvin" , linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org, Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , kvm@vger.kernel.org Subject: Re: [PATCH v2 02/16] x86/mce: WARN once if IA32_FEATURE_CONTROL MSR is left unlocked Message-ID: <20191025142248.GD6483@zn.tnic> References: <20191021234632.32363-1-sean.j.christopherson@intel.com> <20191021235642.418-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20191021235642.418-1-sean.j.christopherson@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-edac-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org On Mon, Oct 21, 2019 at 04:56:42PM -0700, Sean Christopherson wrote: > WARN if the IA32_FEATURE_CONTROL MSR is somehow left unlocked now that > CPU initialization unconditionally locks the MSR. > > Cc: Vitaly Kuznetsov > Cc: Wanpeng Li > Cc: Jim Mattson > Cc: kvm@vger.kernel.org > Signed-off-by: Sean Christopherson > --- > arch/x86/kernel/cpu/mce/intel.c | 7 +++---- > 1 file changed, 3 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/kernel/cpu/mce/intel.c b/arch/x86/kernel/cpu/mce/intel.c > index 88cd9598fa57..1008f14b803b 100644 > --- a/arch/x86/kernel/cpu/mce/intel.c > +++ b/arch/x86/kernel/cpu/mce/intel.c > @@ -117,11 +117,10 @@ static bool lmce_supported(void) > * generate a #GP fault. > */ > rdmsrl(MSR_IA32_FEATURE_CONTROL, tmp); > - if ((tmp & (FEATURE_CONTROL_LOCKED | FEATURE_CONTROL_LMCE)) == > - (FEATURE_CONTROL_LOCKED | FEATURE_CONTROL_LMCE)) > - return true; > + if (WARN_ON_ONCE(!(tmp & FEATURE_CONTROL_LOCKED))) > + return false; > > - return false; > + return tmp & FEATURE_CONTROL_LMCE; > } > > bool mce_intel_cmci_poll(void) > -- Reviewed-by: Borislav Petkov -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette