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=-5.8 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 7776DC433ED for ; Wed, 14 Apr 2021 15:36:12 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1A6DA6112F for ; Wed, 14 Apr 2021 15:36:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1A6DA6112F 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 9C9316B0078; Wed, 14 Apr 2021 11:36:09 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 979776B007B; Wed, 14 Apr 2021 11:36:09 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 81A516B007D; Wed, 14 Apr 2021 11:36:09 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0072.hostedemail.com [216.40.44.72]) by kanga.kvack.org (Postfix) with ESMTP id 667926B0078 for ; Wed, 14 Apr 2021 11:36:09 -0400 (EDT) Received: from smtpin35.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 212B0181AEF3C for ; Wed, 14 Apr 2021 15:36:09 +0000 (UTC) X-FDA: 78031373658.35.A307836 Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by imf09.hostedemail.com (Postfix) with ESMTP id 5E52A6000117 for ; Wed, 14 Apr 2021 15:35:57 +0000 (UTC) Received: from zn.tnic (p200300ec2f0e8f008ccc887bddfa0520.dip0.t-ipconnect.de [IPv6:2003:ec:2f0e:8f00:8ccc:887b:ddfa:520]) (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 F0CF51EC04D6; Wed, 14 Apr 2021 17:35:57 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1618414558; 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=7QUzYLHM4/+zVfpSckS+KvePCizty5xc6tScIXPXiqY=; b=eQvu9OVvEIJVqgHE0EkPsiN9cb3jEblOQMnS33QLuuRHfT0XKfSLzPsBnDTGS+LhCWwPfg mPKQQXzvlsdWkrmjIZEONJniIfaTXS76xpWrbXz9bjgs6+IwLQ+JDWobwo6xHf/ITFBPDT 4Bv5At1ERm6BrmoW9mBWN/ZyHf8WaZc= Date: Wed, 14 Apr 2021 17:35:54 +0200 From: Borislav Petkov To: Jue Wang Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, luto@kernel.org, HORIGUCHI =?utf-8?B?TkFPWUEo5aCA5Y+jIOebtOS5nyk=?= , "Luck, Tony" , x86 , yaoaili@kingsoft.com Subject: Re: [PATCH 3/4] mce/copyin: fix to not SIGBUS when copying from user hits poison Message-ID: <20210414153554.GH10709@zn.tnic> References: <20210414131018.GG10709@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 5E52A6000117 X-Stat-Signature: tz9e5j6ifwpo7ky3iccgmoa63a4bdxs8 Received-SPF: none (alien8.de>: No applicable sender policy available) receiver=imf09; identity=mailfrom; envelope-from=""; helo=mail.skyhub.de; client-ip=5.9.137.197 X-HE-DKIM-Result: invalid/invalid (public key: DNS error: SERVFAIL) X-HE-Tag: 1618414557-150700 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000092, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Apr 14, 2021 at 07:46:49AM -0700, Jue Wang wrote: > I can see this is useful in other types of domains, e.g., on multi-tenant cloud > servers where many VMs are collocated on the same host, > with proper recovery + live migration, a single MCE would only affect a single > VM at most. > > Another type of generic use case may be services that can tolerate > abrupt crash, > i.e., they periodically save checkpoints to persistent storage or are stateless > services in nature and are managed by some process manager to automatically > restart and resume from where the work was left at when crashed. Yap, thanks for those. So I do see a disconnect between us doing those features in the kernel and not really seeing how people use them. So this helps, I guess the VM angle will become important real soon - if not already - so hopefully we'll get more feedback in the future. Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette