netdev - Re: [PATCH 3/4] ptp: add ioctl interface for ptp

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: <CAF2d9jgWpwNye89qrANfngG2+NQPDhpZQjXMKBDG6x7e32_cOw@mail.gmail.com>
Date: Mon, 2 Oct 2023 17:29:58 -0700
From: Mahesh Bandewar (महेश बंडेवार) <maheshb@...gle.com>
To: Richard Cochran <richardcochran@...il.com>
Cc: Netdev <netdev@...r.kernel.org>, Linux <linux-kernel@...r.kernel.org>, 
	David Miller <davem@...emloft.net>, Jakub Kicinski <kuba@...nel.org>, 
	Eric Dumazet <edumazet@...gle.com>, Paolo Abeni <pabeni@...hat.com>, 
	Jonathan Corbet <corbet@....net>, Don Hatchett <hatch@...gle.com>, Yuliang Li <yuliangli@...gle.com>, 
	Mahesh Bandewar <mahesh@...dewar.net>, Rahul Rameshbabu <rrameshbabu@...dia.com>
Subject: Re: [PATCH 3/4] ptp: add ioctl interface for ptp_gettimex64any()

On Sat, Sep 30, 2023 at 2:25 PM Richard Cochran
<richardcochran@...il.com> wrote:
>
> On Thu, Sep 28, 2023 at 07:37:43PM -0700, Mahesh Bandewar wrote:
> > add an ioctl op PTP_SYS_OFFSET_ANY2 to support ptp_gettimex64any() method
>
> This is a useful idea.
>
> But how about a new system call instead?
>
>     clock_compare(clockid_t a, clockid_t b);
>
The purpose of this API is not to compare clocks but to get the width
of reading the MTS value (offered by NICs) in terms of the timebase
that is selected to essentially improve the accuracy.

> It would accept any two clock IDs.
>
> I've been wanting this for a long time, but never found time to
> implement it.
>
> Thanks,
> Richard