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Date:   Tue, 1 Mar 2022 18:42:09 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Dongli Zhang <dongli.zhang@oracle.com>
Cc:     netdev@vger.kernel.org, bpf@vger.kernel.org,
        linux-kernel@vger.kernel.org, davem@davemloft.net,
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        joao.m.martins@oracle.com, joe.jin@oracle.com, dsahern@gmail.com,
        edumazet@google.com
Subject: Re: [PATCH net-next v4 2/4] net: tap: track dropped skb via
 kfree_skb_reason()
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In-Reply-To: <20220226084929.6417-3-dongli.zhang@oracle.com>
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        <20220226084929.6417-3-dongli.zhang@oracle.com>
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On Sat, 26 Feb 2022 00:49:27 -0800 Dongli Zhang wrote:
> +	SKB_DROP_REASON_SKB_CSUM,	/* sk_buff checksum error */

Can we spell it out a little more? It sounds like the checksum was
incorrect. Will it be clear that computing the checksum failed, rather
than checksum validation failed?

> +	SKB_DROP_REASON_SKB_COPY_DATA,	/* failed to copy data from or to
> +					 * sk_buff
> +					 */

Here should we specify that it's copying from user space?

> +	SKB_DROP_REASON_SKB_GSO_SEG,	/* gso segmentation error */
> +	SKB_DROP_REASON_DEV_HDR,	/* there is something wrong with
> +					 * device driver specific header
> +					 */

How about:
device driver specific header / metadata was invalid

to broaden the scope also to devices which don't transfer the metadata
in form of a header?

> +	SKB_DROP_REASON_FULL_RING,	/* ring buffer is full */