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Date: Thu, 10 Sep 2026 17:20:47 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Koichiro Den <den@valinux.co.jp>
Cc: Jon Mason <jdmason@kudzu.us>, Dave Jiang <dave.jiang@intel.com>, Allen
 Hubbe <allenbh@gmail.com>, Andrew Lunn <andrew+netdev@lunn.ch>, "David S.
 Miller" <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>, Paolo
 Abeni <pabeni@redhat.com>, ntb@lists.linux.dev, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next v3 4/4] net: ntb_netdev: Preserve
 CHECKSUM_PARTIAL across NTB
Message-ID: <20260910172047.167225eb@kernel.org>
In-Reply-To: <20260904052134.2970111-5-den@valinux.co.jp>
References: <20260904052134.2970111-1-den@valinux.co.jp>
	<20260904052134.2970111-5-den@valinux.co.jp>
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On Fri,  4 Sep 2026 14:21:34 +0900 Koichiro Den wrote:
> Calculating L4 checksums can limit ntb_netdev throughput especially on
> embedded systems, where CPU resources are often limited. A trusted PCIe
> fabric can avoid that work.

Would it make more sense to prepend something like a virtio_net_hdr
to the data so you can cheaply express more offloads?