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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 7ECADC433B4 for ; Fri, 23 Apr 2021 11:57:35 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C2E2A6144A for ; Fri, 23 Apr 2021 11:57:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C2E2A6144A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=alien8.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id E0F138D0009; Fri, 23 Apr 2021 07:57:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id DC0778D0001; Fri, 23 Apr 2021 07:57:33 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C38298D0009; Fri, 23 Apr 2021 07:57:33 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0100.hostedemail.com [216.40.44.100]) by kanga.kvack.org (Postfix) with ESMTP id A35B98D0001 for ; Fri, 23 Apr 2021 07:57:33 -0400 (EDT) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 5E93F8248047 for ; Fri, 23 Apr 2021 11:57:33 +0000 (UTC) X-FDA: 78063481986.22.F3BE932 Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by imf14.hostedemail.com (Postfix) with ESMTP id 3D8F4C0007E2 for ; Fri, 23 Apr 2021 11:57:19 +0000 (UTC) Received: from zn.tnic (p200300ec2f0cb100de1b78f3b91faa58.dip0.t-ipconnect.de [IPv6:2003:ec:2f0c:b100:de1b:78f3:b91f:aa58]) (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 7B5301EC0118; Fri, 23 Apr 2021 13:57:29 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1619179049; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Hl4owIygIiuL+Uo1VjLb8yx5rvDHEvzCcFzwABb5PYo=; b=cGIDsJufxJejr6m5pU81tTIT5Zyyt/2m8sYjxfkATzMh/3QXpk/K/n8xkzuQocNbCoqnl9 6d8orgS8F0w3utnveodjRJL4h4MBQ6mAb3318hEQ3HyHAWpVgMjvVvq8hjFsTAlSkRFQjT tzlIChMkDT5sk7sIhm7GSvd/E9pb8js= Date: Fri, 23 Apr 2021 13:57:25 +0200 From: Borislav Petkov To: HORIGUCHI =?utf-8?B?TkFPWUEo5aCA5Y+j44CA55u05LmfKQ==?= Cc: Naoya Horiguchi , "linux-mm@kvack.org" , Tony Luck , Aili Yao , Andrew Morton , Oscar Salvador , David Hildenbrand , Andy Lutomirski , Jue Wang , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v3 3/3] mm,hwpoison: add kill_accessing_process() to find error virtual address Message-ID: <20210423115725.GB18085@zn.tnic> References: <20210421005728.1994268-1-nao.horiguchi@gmail.com> <20210421005728.1994268-4-nao.horiguchi@gmail.com> <20210422170213.GE7021@zn.tnic> <20210423021833.GB68967@hori.linux.bs1.fc.nec.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210423021833.GB68967@hori.linux.bs1.fc.nec.co.jp> X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 3D8F4C0007E2 X-Stat-Signature: nh6ceqi8h36s84j3zhbz1e4wj3z4tbh9 Received-SPF: none (alien8.de>: No applicable sender policy available) receiver=imf14; identity=mailfrom; envelope-from=""; helo=mail.skyhub.de; client-ip=5.9.137.197 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1619179039-139399 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Apr 23, 2021 at 02:18:34AM +0000, HORIGUCHI NAOYA(=E5=A0=80=E5=8F= =A3 =E7=9B=B4=E4=B9=9F) wrote: > I don't know exactly. MCE subsystem seems to have code extracting line= ar > address, so I wonder that that could be used as a hint to memory_failur= e() > to find the proper virtual address. See "Table 15-3. Address Mode in IA32_MCi_MISC[8:6]" in the SDM - apparently it can report all kinds of address types, depending on the hw incarnation or MCA bank type or whatnot. Tony knows :) > The situation in question is caused by action required MCE, so > we know which process we should send SIGBUS to. So if we choose > to send SIGBUS to all, no innocent bystanders would be affected. > But when the process have multiple virtual addresses associated > with the error physical address, the process receives multiple > SIGBUSs and all but one have wrong value in si_addr in siginfo_t, > so that's confusing. Is that scenario real or hypothetical? Because I'd expect that if we send it a SIGBUS and we poison that page, then all the VAs mapping it will have to handle the situation that that page has been poisoned and pulled from under them. So from a hw perspective, there won't be any more accesses to the faulty physical page. In a perfect world, that is... --=20 Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette