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Date: Mon, 9 Sep 2024 16:51:16 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>, Sean Anderson
 <sean.anderson@linux.dev>, "David S . Miller" <davem@davemloft.net>, Paolo
 Abeni <pabeni@redhat.com>, netdev@vger.kernel.org, Willem de Bruijn
 <willemb@google.com>, linux-kernel@vger.kernel.org, Shuah Khan
 <shuah@kernel.org>, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH net] selftests: net: csum: Fix checksums for packets
 with non-zero padding
Message-ID: <20240909165116.1bdb4757@kernel.org>
In-Reply-To: <66df2fd2d6595_3bff929459@willemb.c.googlers.com.notmuch>
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	<66dbb4fcbf560_2af86229423@willemb.c.googlers.com.notmuch>
	<9d5bf385-2ef0-435d-b6f9-1de55533653b@linux.dev>
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On Mon, 09 Sep 2024 13:26:42 -0400 Willem de Bruijn wrote:
> > This seems to be a bug in the driver.
> > 
> > A call to skb_put_padto(skb, ETH_ZLEN) should be added.  
> 
> In which case this test detecting it may be nice to have, for lack of
> a more targeted test.

IIUC we're basically saying that we don't need to trim because pad
should be 0? In that case maybe let's keep the patch but add a check 
on top which scans the pad for non-zero bytes, and print an informative
warning?