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=-2.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, USER_AGENT_MUTT autolearn=ham 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 96A1DC433F4 for ; Thu, 20 Sep 2018 08:01:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 341A5214C2 for ; Thu, 20 Sep 2018 08:01:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="z9xMGLCn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 341A5214C2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727165AbeITNnV (ORCPT ); Thu, 20 Sep 2018 09:43:21 -0400 Received: from merlin.infradead.org ([205.233.59.134]:56458 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726028AbeITNnV (ORCPT ); Thu, 20 Sep 2018 09:43:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; 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: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=vZ6XA8wugt+A3IS38Z21yu7WL3GbJVf0Gsr/DnwoCqo=; b=z9xMGLCnzgayydrYpWZq7phof na8jJQugfnF/Lj2/5qT/+UFOHlm59i78dI26RONNBBsUs0ICSsKawRlWXLSWrNZ7izEmjTU26r1xY +mKcaxAq8BPp02r/qVlpr0r98ZQlbB4W5JOPvdeYlNJc6oUJdyCDAVNv8jUZXAsVTTTnB6Xy7wIFc s21gzlRqkre146RfSbSD0iEr8+jt8DT4NbxWq0Vae1VnpL2A9hM0NaLkul4QXxu2XompUTlOw6TNV gFaFKRGyc/Iwf9a+y+dcJdd5axriVKfp3TfxzvgggeJRJ7rnvI2JQg6SYJqueC7GHx/QG4WeXlNQT bmIrVf2zQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1g2ttR-00009W-R0; Thu, 20 Sep 2018 08:00:58 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id F35DF201EC168; Thu, 20 Sep 2018 10:00:53 +0200 (CEST) Date: Thu, 20 Sep 2018 10:00:53 +0200 From: Peter Zijlstra To: Tim Chen Cc: Jiri Kosina , Thomas Gleixner , Tom Lendacky , Ingo Molnar , Josh Poimboeuf , Andrea Arcangeli , David Woodhouse , Andi Kleen , Dave Hansen , Casey Schaufler , Asit Mallick , Arjan van de Ven , Jon Masters , linux-kernel@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH 2/2] x86/speculation: Provide application property based STIBP protection Message-ID: <20180920080053.GM24124@hirez.programming.kicks-ass.net> References: <0c55c162a077aadbfd57878e2694e35292c1a29c.1537392876.git.tim.c.chen@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0c55c162a077aadbfd57878e2694e35292c1a29c.1537392876.git.tim.c.chen@linux.intel.com> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 19, 2018 at 02:35:30PM -0700, Tim Chen wrote: > This patch provides an application property based spectre_v2 > protection with STIBP against attack from another app from > a sibling hyper-thread. For security sensitive non-dumpable > app, STIBP will be turned on before switching to it for Intel > processors vulnerable to spectre_v2. Why does that non dumpable thing make sense? Why not use the same prctl() we already use for SSBD?