netdev - Re: [net-next v3 5/7] igb: reject unsupported external timestamp flags

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20191012183109.GF3165@localhost>
Date:   Sat, 12 Oct 2019 11:31:09 -0700
From:   Richard Cochran <richardcochran@...il.com>
To:     Jacob Keller <jacob.e.keller@...el.com>
Cc:     netdev@...r.kernel.org,
        Intel Wired LAN <intel-wired-lan@...ts.osuosl.org>,
        Jeffrey Kirsher <jeffrey.t.kirsher@...el.com>
Subject: Re: [net-next v3 5/7] igb: reject unsupported external timestamp
 flags

On Thu, Sep 26, 2019 at 11:11:07AM -0700, Jacob Keller wrote:
> Fix the igb PTP support to explicitly reject any future flags that
> get added to the external timestamp request ioctl.
> 
> In order to maintain currently functioning code, this patch accepts all
> three current flags. This is because the PTP_RISING_EDGE and
> PTP_FALLING_EDGE flags have unclear semantics and each driver seems to
> have interpreted them slightly differently.

This HW always time stamps both edges:

  flags                                                 Meaning                   
  ----------------------------------------------------  -------------------------- 
  PTP_ENABLE_FEATURE                                    Time stamp both edges
  PTP_ENABLE_FEATURE|PTP_RISING_EDGE                    Time stamp both edges
  PTP_ENABLE_FEATURE|PTP_FALLING_EDGE                   Time stamp both edges
  PTP_ENABLE_FEATURE|PTP_RISING_EDGE|PTP_FALLING_EDGE   Time stamp both edges
 
> Signed-off-by: Jacob Keller <jacob.e.keller@...el.com>

Reviewed-by: Richard Cochran <richardcochran@...il.com>