From mboxrd@z Thu Jan  1 00:00:00 1970
From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Subject: Re: [PATCH v1 net-next 13/14] net/sched: Enforce usage of CLOCK_TAI
 for sch_etf
Date: Thu, 28 Jun 2018 10:26:40 -0400
Message-ID: <CAF=yD-KnZJgqAspgOvtD82n4x0tB-neUF8THTgRKLo+OR5oE=A@mail.gmail.com>
References: <20180627215950.6719-1-jesus.sanchez-palencia@intel.com> <20180627215950.6719-14-jesus.sanchez-palencia@intel.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Cc: Network Development <netdev@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        jan.altenberg@linutronix.de,
        Vinicius Gomes <vinicius.gomes@intel.com>,
        kurt.kanzenbach@linutronix.de, Henrik Austad <henrik@austad.us>,
        Richard Cochran <richardcochran@gmail.com>,
        Levi Pearson <levi.pearson@harman.com>,
        ilias.apalodimas@linaro.org, ivan.khoronzhuk@linaro.org,
        Miroslav Lichvar <mlichvar@redhat.com>,
        Willem de Bruijn <willemb@google.com>,
        Jamal Hadi Salim <jhs@mojatatu.com>,
        Cong Wang <xiyou.wangcong@gmail.com>,
        =?UTF-8?B?SmnFmcOtIFDDrXJrbw==?= <jiri@resnulli.us>
To: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>
Return-path: <netdev-owner@vger.kernel.org>
Received: from mail-io0-f196.google.com ([209.85.223.196]:46364 "EHLO
        mail-io0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S966385AbeF1O1R (ORCPT
        <rfc822;netdev@vger.kernel.org>); Thu, 28 Jun 2018 10:27:17 -0400
Received: by mail-io0-f196.google.com with SMTP id u23-v6so5413053ioc.13
        for <netdev@vger.kernel.org>; Thu, 28 Jun 2018 07:27:17 -0700 (PDT)
In-Reply-To: <20180627215950.6719-14-jesus.sanchez-palencia@intel.com>
Sender: netdev-owner@vger.kernel.org
List-ID: <netdev.vger.kernel.org>

On Wed, Jun 27, 2018 at 8:45 PM Jesus Sanchez-Palencia
<jesus.sanchez-palencia@intel.com> wrote:
>
> The qdisc and the SO_TXTIME ABIs allow for a clockid to be configured,
> but it's been decided that usage of CLOCK_TAI should be enforced until
> we decide to allow for other clockids to be used. The rationale here is
> that PTP times are usually in the TAI scale, thus no other clocks should
> be necessary.
>
> For now, the qdisc will return EINVAL if any clocks other than
> CLOCK_TAI are used.
>
> Signed-off-by: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>
> ---
>  net/sched/sch_etf.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/net/sched/sch_etf.c b/net/sched/sch_etf.c
> index cd6cb5b69228..5514a8aa3bd5 100644
> --- a/net/sched/sch_etf.c
> +++ b/net/sched/sch_etf.c
> @@ -56,8 +56,8 @@ static inline int validate_input_params(struct tc_etf_qopt *qopt,
>                 return -ENOTSUPP;
>         }
>
> -       if (qopt->clockid >= MAX_CLOCKS) {
> -               NL_SET_ERR_MSG(extack, "Invalid clockid");
> +       if (qopt->clockid != CLOCK_TAI) {
> +               NL_SET_ERR_MSG(extack, "Invalid clockid. CLOCK_TAI must be used");

Similar to the comment in patch 12, this should be squashed (into
patch 6) to avoid incorrect behavior in a range of SHA1s.