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=-3.6 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 6A73FC433E0 for ; Thu, 11 Mar 2021 16:57:14 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6165464FE2 for ; Thu, 11 Mar 2021 16:57:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6165464FE2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A320B8D02D2; Thu, 11 Mar 2021 11:57:12 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 9E1D88D02B2; Thu, 11 Mar 2021 11:57:12 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 85BB88D02D2; Thu, 11 Mar 2021 11:57:12 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0081.hostedemail.com [216.40.44.81]) by kanga.kvack.org (Postfix) with ESMTP id 691EC8D02B2 for ; Thu, 11 Mar 2021 11:57:12 -0500 (EST) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 1CC7512D0 for ; Thu, 11 Mar 2021 16:57:12 +0000 (UTC) X-FDA: 77908198704.30.BF32A22 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) by imf17.hostedemail.com (Postfix) with ESMTP id 98D80407F8DF for ; Thu, 11 Mar 2021 16:57:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ppV5eKP+GTwT8841mn3VqiRD2uTN7WT0z5PGxeKiaTU=; b=JvvWPkglVPY+62xqjH6sjY7+AH dnyYZA6+nBL5WOheOekWnlbQ6GnYvi0waEZ5t4aWCLVN2/uv4qFZ9OrhBNIwQrDxYDa48BDiqtKrL wAkN3RM1PxUTUqOQmW6PXrPB2cHM+bd5wAY56tC6WuekmNVUg7OEF1uYueDAaen3N2TFxZgRCcACb Gy0nfntxV/1oJVsdUGiS1Av+z5v6RBKcIFfTrzPoy/i0uaTqdWIzU6cST62MYG4AXAwSkdp31Bb5T ecWniiVWBTJ6jpgZkDQVrSGGngxUk7BvkGWXIBNwMSfTWmIivDWsN5q1kiFUH8dEHxh9F2Vt8mAg/ sbW9346Q==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1lKOcQ-009cwK-R4; Thu, 11 Mar 2021 16:57:03 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 55DE63013E5; Thu, 11 Mar 2021 17:56:58 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 4110F29E5D623; Thu, 11 Mar 2021 17:56:58 +0100 (CET) Date: Thu, 11 Mar 2021 17:56:58 +0100 From: Peter Zijlstra To: "Luck, Tony" Cc: Andy Lutomirski , Aili Yao , Oleg Nesterov , Linux API , Andy Lutomirski , HORIGUCHI NAOYA , Dave Hansen , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , X86 ML , "yangfeng1@kingsoft.com" , Linux-MM , LKML , "sunhao2@kingsoft.com" Subject: Re: [PATCH v3] x86/fault: Send a SIGBUS to user process always for hwpoison page access. Message-ID: References: <4fc1b4e8f1fb4c8c81f280db09178797@intel.com> <047D5B49-FDBB-494C-81E9-DA811476747D@amacapital.net> <20210311091941.45790fcf@alex-virtual-machine> <0a0909a9005842fa9e49ba9917580e79@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0a0909a9005842fa9e49ba9917580e79@intel.com> X-Stat-Signature: cfrpurmraat7whocsiq6w6ojgstpcpep X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 98D80407F8DF Received-SPF: none (infradead.org>: No applicable sender policy available) receiver=imf17; identity=mailfrom; envelope-from=""; helo=desiato.infradead.org; client-ip=90.155.92.199 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1615481830-506381 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 Thu, Mar 11, 2021 at 04:52:10PM +0000, Luck, Tony wrote: > > I think we need to at least fix the existing bug before we add more > > signals. AFAICS the MCE_IN_KERNEL_COPYIN code is busted for kernel > > threads. > > Can a kernel thread do get_user() or copy_from_user()? Do we have kernel threads > that have an associated user address space to copy from? kthread_use_mm()