netdev - Re: Link down reasons

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-next>] [day] [month] [year] [list]

Message-ID: <20200528084052.n7yeo2nu2vq4eibv@pengutronix.de>
Date:   Thu, 28 May 2020 10:40:52 +0200
From:   Oleksij Rempel <o.rempel@...gutronix.de>
To:     Amit Cohen <amitc@...lanox.com>
Cc:     "andrew@...n.ch" <andrew@...n.ch>, mlxsw <mlxsw@...lanox.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Re: Link down reasons

On Wed, May 27, 2020 at 03:41:22PM +0000, Amit Cohen wrote:
> Hi Andrew,
> We are planning to send a set that exposes link-down reason in ethtool.
> It seems that the ability of your set "Ethernet cable test support" can be integrated with link-down reason.
> 
> The idea is to expose reason and subreason (if there is):
> $ ethtool ethX
> ...
> Link detected: no (No cable) // No sub reason
> 
> $ ethtool ethY
> Link detected: no (Autoneg failure, No partner detected)
> 
> Currently we have reason "cable issue" and subreasons "unsupported cable" and "shorted cable".
> The mechanism of cable test can be integrated and allow us report "cable issue" reason and "shorted cable" subreason.
> 
> However, the way the kernel reports the results of the cable test (cable-test, some seconds, get-result) may be problematic with link-down reason concept.
> We can ignore this information when reporting link-down reason, or report only if testing cable have a result,
> or maybe start testing cable and meanwhile report something like "discovery in progress". But all the options are not perfect.
> 
> We would like to know your opinion about it.

I would add some more reasons:
- master slave resolution issues: both link partners are master or
  slave.
- signal quality drop. In this case driver should be extended to notify
  the system if SQI is under some configurable limit.


Regards,
Oleksij
-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)