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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 A6238CA90AF for ; Wed, 13 May 2020 11:49:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E0A320740 for ; Wed, 13 May 2020 11:49:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726168AbgEMLtT (ORCPT ); Wed, 13 May 2020 07:49:19 -0400 Received: from foss.arm.com ([217.140.110.172]:44196 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726024AbgEMLtT (ORCPT ); Wed, 13 May 2020 07:49:19 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 90F0530E; Wed, 13 May 2020 04:49:18 -0700 (PDT) Received: from arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id ABC773F71E; Wed, 13 May 2020 04:49:17 -0700 (PDT) Date: Wed, 13 May 2020 12:49:15 +0100 From: Dave Martin To: "Michael Kerrisk (man-pages)" Cc: linux-man@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Tim Chen , Thomas Gleixner Subject: Re: [PATCH 10/14] prctl.2: Add PR_SPEC_INDIRECT_BRANCH for SPECULATION_CTRL prctls Message-ID: <20200513114915.GL21779@arm.com> References: <1589301419-24459-1-git-send-email-Dave.Martin@arm.com> <1589301419-24459-11-git-send-email-Dave.Martin@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-man-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-man@vger.kernel.org On Wed, May 13, 2020 at 01:21:12PM +0200, Michael Kerrisk (man-pages) wrote: > Hello Dave, > > On 5/12/20 6:36 PM, Dave Martin wrote: > > Add the PR_SPEC_INDIRECT_BRANCH "misfeature" added in Linux 4.20 > > for PR_SET_SPECULATION_CTRL and PR_GET_SPECULATION_CTRL. > > > > Signed-off-by: Dave Martin > > Cc: Tim Chen > > Cc: Thomas Gleixner > > Thanks. Patch applied, but not yet pushed while I wait to see if any > Review/Ack arrives. > > Also, could you please check the tweaks I note below. > > > --- > > man2/prctl.2 | 24 ++++++++++++++++++------ > > 1 file changed, 18 insertions(+), 6 deletions(-) > > > > diff --git a/man2/prctl.2 b/man2/prctl.2 > > index e8eaf95..66417cf 100644 > > --- a/man2/prctl.2 > > +++ b/man2/prctl.2 > > @@ -1213,11 +1213,20 @@ arguments must be specified as 0; otherwise the call fails with the error > > .\" commit 356e4bfff2c5489e016fdb925adbf12a1e3950ee > > Sets the state of the speculation misfeature specified in > > .IR arg2 . > > -Currently, the only permitted value for this argument is > > +Currently, this argument must be one of: > > +.RS > > +.TP > > .B PR_SPEC_STORE_BYPASS > > -(otherwise the call fails with the error > > +speculative store bypass control, or > > s/speculative/enable speculative/ > > > +.\" commit 9137bb27e60e554dab694eafa4cca241fa3a694f > > +.TP > > +.BR PR_SPEC_INDIRECT_BRANCH " (since Linux 4.20)" > > +indirect branch speculation control. > > s/indirect/enable indirect/ That doesn't seem quite right. arg2 just identifies what behaviour to configure. It's arg3 that says whether to disable / enable it or whatever. While editing this I did wonder whether the "control" was helpful. Maybe just dropping that word from these entries would help. [...] Cheers ---Dave