netdev - Re: [PATCH net-next] net: Make RX-FCS and LRO mutually exclusive

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: <20180305.102704.1651195672970401906.davem@davemloft.net>
Date:   Mon, 05 Mar 2018 10:27:04 -0500 (EST)
From:   David Miller <davem@...emloft.net>
To:     galp@...lanox.com
Cc:     netdev@...r.kernel.org, tariqt@...lanox.com
Subject: Re: [PATCH net-next] net: Make RX-FCS and LRO mutually exclusive

From: Gal Pressman <galp@...lanox.com>
Date: Sun,  4 Mar 2018 14:12:04 +0200

> LRO and RX-FCS offloads cannot be enabled at the same time since it is
> not clear what should happen to the FCS of each coalesced packet.
> The FCS is not really part of the TCP payload, hence cannot be merged
> into one big packet. On the other hand, providing one big LRO packet
> with one FCS contradicts the RX-FCS feature goal.
> 
> Use the fix features mechanism in order to prevent intersection of the
> features and drop LRO in case RX-FCS is requested.
> 
> Enabling RX-FCS while LRO is enabled will result in:
> $ ethtool -K ens6 rx-fcs on
> Actual changes:
> large-receive-offload: off [requested on]
> rx-fcs: on
> 
> Signed-off-by: Gal Pressman <galp@...lanox.com>
> Reviewed-by: Tariq Toukan <tariqt@...lanox.com>

Agreed, having these two options enabled at the same time doesn't
make any sense.

Applied.

Probably need to add the same restriction for HW GRO.