Received: by 2002:a25:ad19:0:0:0:0:0 with SMTP id y25csp4666403ybi; Mon, 15 Jul 2019 12:40:44 -0700 (PDT) X-Google-Smtp-Source: APXvYqyfiA7EIvnA6Qh6aKydavkV46z5wzPXCk1MWXby+W9FQ8twRfyPvGIXljeUl9iaHA5ULV3m X-Received: by 2002:a63:553:: with SMTP id 80mr29592992pgf.280.1563219644717; Mon, 15 Jul 2019 12:40:44 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1563219644; cv=none; d=google.com; s=arc-20160816; b=0CJTt6Ef5nGl+L1rRhKqW8bHyS8DyAw4z8HjXdGUj6yyt1aYggfAV/WZ69sTlN6+et 0MJTfY0UyKnEa0Vt3xzbgQBz0Ud3GONOjevEZ4jaKNcdQ30PcaAXovFH2YjivGZhf1qD ejO5nOIg8Fc3YFHwlnpr8wsmRUD4HMcmwfCv0gLLAIajATZNVtFAo52UYZ8U08pPuOCM uXuPpa6EnL3Gyg/FTas1Mc464XN51ufUE2baZ8xx42F9FIiVpdAn/s1OB57c+kqErvyq LxPY/2CdFZA/+btT2m8pp4UoFgF34xUrw9zwd1lFsEf8s0TwZEkp7biBnRjgB7K4I6RU bYEQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date; bh=bpCxXMGE8dR3a3yX/WdvfE9nrnXcbJfHfPG/1XGfTWM=; b=fFxMZSTTn2qVgVFAUNsFuaVYvXTnCNuLnN9WN5DYxx+35bx782jSbGdfp0oR37zRv3 nI41lI9Mvu0otqV2H1r/0Brk1FGjb83ai2hUhHaMT1V57wm4/cKDQhCODSnaGtdCAn/i lPNcjhw+QNG6RcXkumvv4FznjSame39p3k0DlUqEre+BjLRDnok/EC9L9jNVH70PkFxl 3BQmK6ySShihTgBHjXXcj38QCSdVJ8P+FMHYUBUqLApcjq5I1gw+rVL2ibqTSbh1NaoY 9yAePn+dOGupu6AKg6GLgCc1mkh4E/racq/uwgEUsaDPLGPezn7VWqzxKVTccBGRcyfp omNQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id f12si16443605plr.211.2019.07.15.12.40.28; Mon, 15 Jul 2019 12:40:44 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731414AbfGOTjj (ORCPT + 99 others); Mon, 15 Jul 2019 15:39:39 -0400 Received: from mga09.intel.com ([134.134.136.24]:61122 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730362AbfGOTji (ORCPT ); Mon, 15 Jul 2019 15:39:38 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Jul 2019 12:39:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,494,1557212400"; d="scan'208";a="169703518" Received: from tassilo.jf.intel.com (HELO tassilo.localdomain) ([10.7.201.137]) by orsmga003.jf.intel.com with ESMTP; 15 Jul 2019 12:39:38 -0700 Received: by tassilo.localdomain (Postfix, from userid 1000) id 2F885301AE9; Mon, 15 Jul 2019 12:39:38 -0700 (PDT) Date: Mon, 15 Jul 2019 12:39:38 -0700 From: Andi Kleen To: Thomas Gleixner Cc: Uros Bizjak , linux-kernel@vger.kernel.org, x86@kernel.org, Andrew Lutomirski Subject: Re: [RFC PATCH, x86]: Disable CPA cache flush for selfsnoop targets Message-ID: <20190715193938.GG32439@tassilo.jf.intel.com> References: <8736j7gsza.fsf@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Right, we don't know where the PAT invocation comes from and whether they > are safe to omit flushing the cache. The module load code would be one > obvious candidate. Module load just changes the writable/executable status, right? That shouldn't need to flush in any case because it doesn't change the caching attributes. -Andi