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=-4.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 E88A0C433E9 for ; Thu, 3 Sep 2020 16:55:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 928B3206A5 for ; Thu, 3 Sep 2020 16:55:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="bEpWIzHe" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728827AbgICQzi (ORCPT ); Thu, 3 Sep 2020 12:55:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58708 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726327AbgICQzh (ORCPT ); Thu, 3 Sep 2020 12:55:37 -0400 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00D3DC061244 for ; Thu, 3 Sep 2020 09:55:36 -0700 (PDT) Received: from zn.tnic (p200300ec2f0d7a00e86b50da0ecac743.dip0.t-ipconnect.de [IPv6:2003:ec:2f0d:7a00:e86b:50da:eca:c743]) (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 101CD1EC0472; Thu, 3 Sep 2020 18:55:35 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1599152135; 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=OPLKDPg36zeWZWe6d3dsjH2xBLWDSt7X8K+c+Hl/bOU=; b=bEpWIzHe3bAC0D37QeSHaxowNs23STJ3pPgtRincOzsFA4Sq/fSWgvohTrWlv9rTfXQrlr IFANXHaT3iRVchu7ehzARXIQ6f5t+IZvTuOy80HZhleImgEWxWmFQoziOXoQKiywI0nvwc NZHIwazOM0AexBG/Nt2l3KdKvLj0sgM= Date: Thu, 3 Sep 2020 18:55:30 +0200 From: Borislav Petkov To: Tony Luck Cc: Naoya Horiguchi , Andrew Morton , Youquan Song , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [RFD PATCH] x86/mce: Make sure to send SIGBUS even after losing the race to poison a page Message-ID: <20200903165530.GE5462@zn.tnic> References: <20200827163205.23096-1-tony.luck@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200827163205.23096-1-tony.luck@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 27, 2020 at 09:32:05AM -0700, Tony Luck wrote: > The #MC used to win that race and the page was taken offline and SIGBUS > sent to the task. > > Changes to how Linux processes machine checks now mean that: > a) Linux will offline the page based on the UCNA siganture in the > CMCI handler. Let's see if that logic makes sense: if #MC offlines the page and sends SIGBUS but CMCI only offlines the page, isn't it only logical for the CMCI to *also* send the SIGBUS too, after having offlined the page? I.e., both should do the proper and full recovery action. Just sayin... -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette