netdev - Re: [PATCH net-next] net: dsa: tag_rtl4_a: Drop bit 9 from egress frames

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:   Wed, 15 Sep 2021 15:19:01 +0800
From:   DENG Qingfang <dqfext@...il.com>
To:     Linus Walleij <linus.walleij@...aro.org>
Cc:     Andrew Lunn <andrew@...n.ch>,
        Vivien Didelot <vivien.didelot@...il.com>,
        Florian Fainelli <f.fainelli@...il.com>,
        Vladimir Oltean <olteanv@...il.com>,
        "David S . Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>, netdev@...r.kernel.org
Subject: Re: [PATCH net-next] net: dsa: tag_rtl4_a: Drop bit 9 from egress frames

On Mon, Sep 13, 2021 at 04:31:56PM +0200, Linus Walleij wrote:
> This drops the code setting bit 9 on egress frames on the
> Realtek "type A" (RTL8366RB) frames.

FYI, on RTL8366S, bit 9 on egress frames is disable learning.

> This bit was set on ingress frames for unknown reason,

I think it could be the reason why the frame is forwarded to the CPU.

> and was set on egress frames as the format of ingress
> and egress frames was believed to be the same. As that
> assumption turned out to be false, and since this bit
> seems to have zero effect on the behaviour of the switch
> let's drop this bit entirely.
> 
> Signed-off-by: Linus Walleij <linus.walleij@...aro.org>