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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 7E337C433DF for ; Fri, 29 May 2020 13:38:03 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4BD98206F1 for ; Fri, 29 May 2020 13:38:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=xen.org header.i=@xen.org header.b="KuaznYQ7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4BD98206F1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xen.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jefCY-0001Ov-UR; Fri, 29 May 2020 13:37:34 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jefCX-0001Oq-V8 for xen-devel@lists.xenproject.org; Fri, 29 May 2020 13:37:34 +0000 X-Inumbo-ID: 8ca936d7-a1b1-11ea-a8b7-12813bfff9fa Received: from mail.xenproject.org (unknown [104.130.215.37]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 8ca936d7-a1b1-11ea-a8b7-12813bfff9fa; Fri, 29 May 2020 13:37:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=gRMf3JL5qzUN0yHgRk3JM7qMoHl49Y05x8/7LcQXiuw=; b=KuaznYQ7X8KHbVDAllbBAhop1T ceasurU4g6hde745U42si5i9HGciEimH+biicEvPADFBkr0v/pUGy+4xN6nL6FWWab3Lb29tKgKJm PBTfC9Urkp4YLF7PkZo6LpgnWAvDnXchtXzFNkjBrEuJ7wQXP8wQrb6XfK7rm4JA7YXc=; Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1jefCS-0005Tl-Ef; Fri, 29 May 2020 13:37:28 +0000 Received: from [54.239.6.187] (helo=a483e7b01a66.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1jefCR-0008DK-VP; Fri, 29 May 2020 13:37:28 +0000 Subject: Re: [RFC PATCH 1/1] xen: Use a global mapping for runstate To: =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= , Bertrand Marquis References: <03e7cd740922bfbaa479f22d81d9de06f718a305.1590675919.git.bertrand.marquis@arm.com> <20200529132020.GN1195@Air-de-Roger> From: Julien Grall Message-ID: Date: Fri, 29 May 2020 14:37:24 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.8.1 MIME-Version: 1.0 In-Reply-To: <20200529132020.GN1195@Air-de-Roger> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Stefano Stabellini , Wei Liu , "paul@xen.org" , Andrew Cooper , Ian Jackson , George Dunlap , "Xia, Hongyan" , Jan Beulich , xen-devel , nd , Volodymyr Babchuk Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Hi, On 29/05/2020 14:26, Roger Pau Monné wrote: > TBH I would just remove the error message on Arm from the current > hypercall, I don't think it's useful. The message is part of the helpers get_page_from_gva() which is also used by copy_{to, from}_guest. While it may not be useful in the context of the runstate, it was introduced because there was some other weird bug happening before KPTI even existed (see [1]). I haven't yet managed to find the bottom line of the issue. So I would still very much like to keep the message in place. Although we could reduce the number of cases where this is hapenning based on the fault. Note this is a dprintk(XENLOG_G_DEBUG,...) so the verbosity of the logging is only for debug build. Cheers, [1] https://lists.xen.org/archives/html/xen-devel/2017-11/msg00942.html -- Julien Grall