netdev - Re: CRC errors between mvneta and macb

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]

Date:   Mon, 22 Oct 2018 08:51:55 +0200
From:   Richard Genoud <richard.genoud@...il.com>
To:     linux-kernel@...r.kernel.org,
        Richard Genoud <richard.genoud@...il.com>
Cc:     Thomas Petazzoni <thomas.petazzoni@...tlin.com>,
        Antoine Tenart <antoine.tenart@...tlin.com>,
        Gregory CLEMENT <gregory.clement@...tlin.com>,
        Yelena Krivosheev <yelena@...vell.com>,
        Maxime Chevallier <maxime.chevallier@...tlin.com>,
        Nicolas Ferre <nicolas.ferre@...rochip.com>,
        netdev@...r.kernel.org
Subject: Re: CRC errors between mvneta and macb

Le 19/10/2018 à 17:44, Willy Tarreau a écrit :
> On Fri, Oct 19, 2018 at 05:15:03PM +0200, Richard Genoud wrote:
>> When there's a CRC error, the TXCLK has its polarity inverted...
>> That's a clue !
>>
>> But this TXCLK (25MHz) is not used on the g35-ek.
>> Only the REFCLK/XT2 (50MHz) is used to synchronise the PHY and the macb.
>> So I guess that the TXCLK has a role to play to generate TX+/TX-
> 
> Well, just a stupid idea, maybe when this signal is inverted, the TX+/TX-
> are desynchronized by half a clock and are not always properly interpreted
> on the other side ?
> 
> Willy
> 

I must admit that I'm not familiar with the PHY internals, I'll have to
dig into that.

Richard.