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Date: Wed, 25 Feb 2026 16:27:25 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: "Russell King (Oracle)" <linux@armlinux.org.uk>
Cc: Andrew Lunn <andrew@lunn.ch>, Alexandre Torgue
 <alexandre.torgue@foss.st.com>, Andrew Lunn <andrew+netdev@lunn.ch>, "David
 S. Miller" <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>,
 linux-arm-kernel@lists.infradead.org,
 linux-stm32@st-md-mailman.stormreply.com, netdev@vger.kernel.org, Paolo
 Abeni <pabeni@redhat.com>
Subject: Re: [PATCH net-next] net: stmmac: fix .ndo_fix_features()
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On Wed, 25 Feb 2026 10:27:09 +0000 Russell King (Oracle) wrote:
> The options as I see it are:
> 1. scan the transmit queue configuration, if any have TBS enabled,
>    disable TSO support for the entire interface.
> 
> or
> 
> 2. rip out TSO support, making the code simpler, and thereby removing
>    the need to try and fix the problems here, and making this patch
>    unnecessary.

normally corner cases like this TSO + TBS thing are handled in
.ndo_features_check. The driver can selectively clear the TSO
feature for a single packet it sees heading down the stack
towards its TBS queue. The stack will then run GSO and feed 
it segments one by one.

FWIW Andrew's suggestion to do the GSO in the driver is very much
legit, but I agree that its orthogonal if you're trying to simply
fix brokenness.