Re: [PATCH net-next] selftests: drv-net: gro: signal over-coalescing more reliably

[Paolo Abeni <pabeni@redhat.com>]

On 6/9/26 4:53 AM, Jakub Kicinski wrote:
> On Sat,  6 Jun 2026 17:24:01 -0700 Jakub Kicinski wrote:
>> +	/* Signal over-coalescing explicitly, it's a hard failure, unlike
>> +	 * under-coalescing which could be timing- or loss-related.
>> +	 */
>> +	if (num_pkt < correct_num_pkts && bytes_received == bytes_expected)
>> +		error(EXIT_OVER_COALESCE, 0,
>> +		      "over-coalesced: got %d pkts vs expected %d (%d B)",
>> +		      num_pkt, correct_num_pkts, bytes_received);
> 
> Sashiko complains that this condition may mis-fire if we lose a zero-len
> RST or ACK. This is true, tho, if the device drops pure acks ignoring
> failures where ack disappeared puts us back at risk of false negatives.
> Happy to respin but feels like we only have bad choices here..

My personal take here is that packet loss at (very) low rate in a
controlled environment should be threaded as fatal: I think the patch in
the current form is the better option.

/P