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Date: Tue, 17 Dec 2024 16:35:38 +0000
From: Simon Horman <horms@kernel.org>
To: Furong Xu <0x1207@gmail.com>
Cc: netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com,
	linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
	Alexandre Torgue <alexandre.torgue@foss.st.com>,
	Jose Abreu <joabreu@synopsys.com>,
	Andrew Lunn <andrew+netdev@lunn.ch>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>, xfr@outlook.com
Subject: Re: [PATCH net v1] net: stmmac: Drop useless code related to ethtool
 rx-copybreak
Message-ID: <20241217163538.GU780307@kernel.org>
References: <20241217091712.383911-1-0x1207@gmail.com>
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In-Reply-To: <20241217091712.383911-1-0x1207@gmail.com>

On Tue, Dec 17, 2024 at 05:17:12PM +0800, Furong Xu wrote:
> After commit 2af6106ae949 ("net: stmmac: Introducing support for Page
> Pool"), these code turned to be useless and users of ethtool may get
> confused about the unhandled rx-copybreak parameter.

Hi Furong Xu,

I think it would be useful to explain why the change cited above
renders the copybreak implementation unnecessary.

> 
> This patch mostly reverts
> commit 22ad38381547 ("stmmac: do not perform zero-copy for rx frames")
> 
> Fixes: 2af6106ae949 ("net: stmmac: Introducing support for Page Pool")

Based on your description this feels more like an enhancement
for net-next, without a Fixes tag, than a fix for net.

> Signed-off-by: Furong Xu <0x1207@gmail.com>

...