Re: [PATCH linux-next 1/3] selftests: net: udpgso_bench_rx: Fix verifty exceptions

[Paolo Abeni <pabeni@redhat.com>]

On Mon, 2023-04-17 at 20:24 +0800, Yang Yang wrote:
> From: Zhang Yunkai (CGEL ZTE) <zhang.yunkai@zte.com.cn>
> 
> The verification function of this test case is likely to encounter the
> following error, which may confuse users.
> 
> Executing the following command fails:
> bash# udpgso_bench_tx -l 4 -4 -D "$DST"
> bash# udpgso_bench_tx -l 4 -4 -D "$DST" -S 0
> bash# udpgso_bench_rx -4 -G -S 1472 -v
> udpgso_bench_rx: data[1472]: len 2944, a(97) != q(113)


As noted by Willem, both the commit message and the above command
sequence is quite confusing. Please reorder the commands in the exact
sequence you run them, presumably:

udpgso_bench_rx -4 -G -S 1472 -v &
udpgso_bench_tx -l 4 -4 -D "$DST" -S 0


> This is because the sending buffers are not aligned by 26 bytes, and the
> GRO is not merged sequentially, and the receiver does not judge this
> situation. We do the validation after the data is split at the receiving
> end, just as the application actually uses this feature.

The wording from Willem response is much more clear. If applicable,
please use such text.

BTW I could not reproduce the issue with any permutation of the
suggested commands I could think of, so possibly that section need some
extra clarification.

Thanks,

Paolo