From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Martin Subject: Re: [PATCH 10/14] prctl.2: Add PR_SPEC_INDIRECT_BRANCH for SPECULATION_CTRL prctls Date: Wed, 13 May 2020 12:49:15 +0100 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 Return-path: 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 Content-Disposition: inline In-Reply-To: Sender: linux-arch-owner@vger.kernel.org List-ID: 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 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 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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,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 EA16FCA90AF for ; Wed, 13 May 2020 11:49:22 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B74FD20740 for ; Wed, 13 May 2020 11:49:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="O7quTbYI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B74FD20740 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=HJNXrZMyGrP8QNwPwoaPff7qcspiTWpgUBYFGPNCtaQ=; b=O7quTbYI1i26UQ E0cftvyBsxXWeoRygWoQCOul/noy57JcOyGrhyn8aQFp9XypZrXMPL/WpqkAv0OW139LEk4LoZchx vkjFlfrDvP6P/EtoPB4EPWZVtHkIgBiNMVmFlS3VVCRTUxi4vVVVeOnX2i08uWTQneZkzrsrV/P2A 5GRCPx7cbNKTDOcNshGJNltfdpe99kgG0ZRIMCD54DS8VFtYp9hxQ2802FhdU9SSuwNyNbQgulYdK fFkarT9+MxT/1KhtUIiFcz5M6r/r1tVsPhZYVZ/GC5s1uVTFOIEoEZuBDKVkIutkVfwwWRwjEKp3J UVg2VOdmPKgk6fKlv+SQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jYpt4-00059E-1y; Wed, 13 May 2020 11:49:22 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jYpt1-00058D-61 for linux-arm-kernel@lists.infradead.org; Wed, 13 May 2020 11:49:20 +0000 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)" 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-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200513_044919_269662_A49A56AD X-CRM114-Status: GOOD ( 19.88 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, linux-man@vger.kernel.org, Thomas Gleixner , Tim Chen , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel