Received: by 10.223.185.116 with SMTP id b49csp2349156wrg; Thu, 15 Feb 2018 10:12:19 -0800 (PST) X-Google-Smtp-Source: AH8x224GxFQKt8kA18xBg5UEdWVTYBMlSto4g3ASgme8jOdyKPa9rq4+anuZjPcw8ckx+sbz5fsS X-Received: by 2002:a17:902:5914:: with SMTP id o20-v6mr3278158pli.60.1518718339771; Thu, 15 Feb 2018 10:12:19 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1518718339; cv=none; d=google.com; s=arc-20160816; b=UXRVOMMk4cMrnbwWTIvxVHje6en9D4PasH0P0EIG6UsamyHnRRHupei1A4eTnMPIBC w+awdaoXocj5j7lNmAlA0CTm/V6C1oKYXTldoLyc2mTtMuCk6jiAt+1vA8G+jYVaqxwE 4p92E9JK+5fVpp5LYFXSNZu/JmehcrPP5JQPmJPoCiNArgwCYzNkXJl+3Y7IXg+INGnc fAfyeDXctxMu07xCa8JXvHxsx3koAOgsKIfD/qYmRP4HyDujeTQK+9zLA85A5JsOhOdn JeFuXf1P7zRb7D8dUeH86T5WTPKTSvOU8vPFK8JuwwP1ibEZNYWQv5ouF1ArJr7ngY9W vupw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding :content-language:in-reply-to:mime-version:user-agent:date :message-id:from:cc:references:to:subject:arc-authentication-results; bh=sO8VKOjBMY8GET6cQ9Kh3REtNFRenJa8VK8GCSWtM90=; b=gI9GmjF6H5Rf7F0viSilf35tP+lwleKp4Yy9fzXN/oi7uOLVSCsGONJSbVvc4llpX5 pIqpzEVnGO9kX3ZrFo+B/SW/RNJqDsOtQtSbr+hWQEguPS8rsgzrPkzhfTyqLnE99SzV MM1p+uhFZtnLK9mDwAVyHoHUnzEDP4A/EfFqW+pV2P+cUvmQug5gqLOpu+pbqpiFw09D c/FwF+dyez+AaHgBPZbT5LMvZn8pdXdAomtGgo+QJU146rlRnnxLpxPd/B5jU3XVEEqJ ntHrfZutxXKAiaAALsJf3tSj1G8lR8+B1pbqXMhruQuAbteCEiKKLJwneZ3jsRZqgTxq 6Fig== 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 Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id d4si1370464pgq.82.2018.02.15.10.12.04; Thu, 15 Feb 2018 10:12:19 -0800 (PST) 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 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1166090AbeBOSKW (ORCPT + 99 others); Thu, 15 Feb 2018 13:10:22 -0500 Received: from mga12.intel.com ([192.55.52.136]:50369 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1163370AbeBOSKV (ORCPT ); Thu, 15 Feb 2018 13:10:21 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Feb 2018 10:10:20 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.46,517,1511856000"; d="scan'208";a="18781483" Received: from makhan1-mobl.amr.corp.intel.com (HELO [10.254.69.204]) ([10.254.69.204]) by orsmga006.jf.intel.com with ESMTP; 15 Feb 2018 10:10:20 -0800 Subject: Re: [PATCH RFC v2 1/6] x86: Skip PTI when disable indication is set To: Nadav Amit , Ingo Molnar References: <20180215163602.61162-1-namit@vmware.com> <20180215163602.61162-2-namit@vmware.com> Cc: Thomas Gleixner , Andy Lutomirski , Peter Zijlstra , Willy Tarreau , Nadav Amit , x86@kernel.org, linux-kernel@vger.kernel.org From: Dave Hansen Message-ID: <7057a6cc-f3ea-8826-5440-61e0154950da@linux.intel.com> Date: Thu, 15 Feb 2018 10:10:19 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180215163602.61162-2-namit@vmware.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/15/2018 08:35 AM, Nadav Amit wrote: > +.Lno_spec_\@: > + lfence > + jmp .Lend_\@ > + > .Lnoflush_\@: > SET_NOFLUSH_BIT \save_reg > How expensive is this?