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Date:   Mon, 21 Dec 2020 10:54:19 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Eric Dumazet <edumazet@google.com>
Cc:     Ben Greear <greearb@candelatech.com>,
        Rainer Suhm <automat@posteo.de>,
        Johannes Berg <johannes@sipsolutions.net>,
        Luca Coelho <luciano.coelho@intel.com>,
        netdev <netdev@vger.kernel.org>, linux-wireless@vger.kernel.org,
        Willem de Bruijn <willemb@google.com>
Subject: Re: net: tso: add UDP segmentation support: adds regression for
 ax200 upload
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On Mon, 21 Dec 2020 19:46:23 +0100 Eric Dumazet wrote:
> So maybe the issue is coming from traffic coming from a VM through a
> tun device or something,
> and our handling of GSO_ROBUST / DODGY never cared about setting
> SKB_GSO_TCPV4 or SKB_GSO_TCPV6 if not already given by user space ?
> 
> Or a plain bug somewhere, possibly overwriting  gso_type with 0 or garbage...

Hm, the Arch Linux forum thread linked from the kernel bugzilla
has the user complaining about NFS performance.