From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755059AbeDWMqL (ORCPT ); Mon, 23 Apr 2018 08:46:11 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:42390 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754802AbeDWMqK (ORCPT ); Mon, 23 Apr 2018 08:46:10 -0400 Date: Mon, 23 Apr 2018 14:45:52 +0200 From: Peter Zijlstra To: "Gustavo A. R. Silva" Cc: Dan Carpenter , linux-kernel@vger.kernel.org, Ingo Molnar , Thomas Gleixner , dan.j.williams@intel.com, Linus Torvalds Subject: Re: Smatch check for Spectre stuff Message-ID: <20180423124552.GY4064@hirez.programming.kicks-ass.net> References: <20180419051510.GA21898@mwanda> <20180420120044.GN4064@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.3 (2018-01-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 23, 2018 at 07:31:03AM -0500, Gustavo A. R. Silva wrote: > Hi Peter, > > On 04/20/2018 07:00 AM, Peter Zijlstra wrote: > > > > Hi Dan, > > > > awesome stuff... > > > > So I fear that many are actually things we want to fix. Our policy was > > to kill the speculation on the first load and not worry if it can be > > completed with a dependent load/store. > > > I wonder if there is any thread where I can read the discussion about that > policy that you mention. > > Could you share it here, please? I think it was somewhere in the many spectre variant1 threads when Linus Alexei and Dan W were hashing out the mitigation thing. I cannot quickly find the specific email. Clarifying that position was one reason for the patches I did, Linus and Dan W are on Cc and I figure that if they all agree we should maybe add a little something to Documentation/speculation.txt.