Re: [PATCH v6] net/i40e: rework maximum frame size configuration

[Kevin Traynor <ktraynor@redhat.com>]

On 24/03/2023 06:32, Jiang, YuX wrote:
>> -----Original Message-----
>> From: Kevin Traynor <ktraynor@redhat.com>
>> Sent: Thursday, March 23, 2023 10:51 PM
>> To: Zhang, Qi Z <qi.z.zhang@intel.com>; Su, Simei <simei.su@intel.com>; Xing,
>> Beilei <beilei.xing@intel.com>; Zhang, Yuying <yuying.zhang@intel.com>;
>> david.marchand@redhat.com; Jiang, YuX <yux.jiang@intel.com>
>> Cc: dev@dpdk.org; Yang, Qiming <qiming.yang@intel.com>; stable@dpdk.org;
>> Luca Boccassi <bluca@debian.org>; Mcnamara, John
>> <john.mcnamara@intel.com>
>> Subject: Re: [PATCH v6] net/i40e: rework maximum frame size configuration
>>
>> On 22/03/2023 16:50, Kevin Traynor wrote:
>>> On 27/02/2023 00:35, Zhang, Qi Z wrote:
>>>>
>>>
>>> Hi Simei/Qi/Yu
>>>
>>
>> Hi Yu,
>>
>>>>
>>>>> -----Original Message-----
>>>>> From: Su, Simei <simei.su@intel.com>
>>>>> Sent: Monday, February 20, 2023 4:00 PM
>>>>> To: Xing, Beilei <beilei.xing@intel.com>; Zhang, Yuying
>>>>> <yuying.zhang@intel.com>; Zhang, Qi Z <qi.z.zhang@intel.com>;
>>>>> david.marchand@redhat.com
>>>>> Cc: dev@dpdk.org; Yang, Qiming <qiming.yang@intel.com>; Su, Simei
>>>>> <simei.su@intel.com>; stable@dpdk.org
>>>>> Subject: [PATCH v6] net/i40e: rework maximum frame size
>>>>> configuration
>>>>>
>>>>> One issue is reported by David Marchand that error occurs in OVS due
>>>>> to the fix patch in mentioned changes below. The detailed reproduce
>>>>> step and result are in
>>>>> https://patchwork.dpdk.org/project/dpdk/patch/
>>>>> 20211207085946.121032-1-dapengx.yu@intel.com/.
>>>>>
>>>>> This patch removes unnecessary link status check and directly sets
>>>>> mac config in dev_start. Also, it sets the parameter "wait to
>>>>> complete" true to wait for more time to make sure adminq command
>> execute completed.
>>>>>
>>>
>>>>> Fixes: a4ba77367923 ("net/i40e: enable maximum frame size at port
>>>>> level")
>>>>> Fixes: 2184f7cdeeaa ("net/i40e: fix max frame size config at port
>>>>> level")
>>>>> Fixes: 719469f13b11 ("net/i40e: fix jumbo frame Rx with X722")
>>>>> Cc: stable@dpdk.org
>>>
>>> These patches caused an observable regression in multiple 20.11 and
>>> 21.11 LTS releases that was only caught a long time after releases.
>>>
>>> Is there anything being added to LTS validation for regression testing
>>> this issue, so we don't get caught again?
>>>
>>
>> This is the issue I was talking about earlier during the release meeting. Not sure
>> if we were talking about the same patch.
>>
>> I was asking if there are some regression tests added/can be added to LTS
>> validation that will be run during each LTS validation cycle so we don't have any
>> more regressions on it.
>>
> Hi Kevin,
> Thanks for your comments.
> Yes. We are adding additional case to cover more testing. For main branch, we have done the regression testing (including the additional case testing), they both work well.

That's good to hear. Will the additional regression tests also be added 
to the LTS validation tests when they are run?

> We hope the two related patches can be backported to LTS branch, and the second patch just reworks for previous bug's fix.
> 	Patch1: https://patchwork.dpdk.org/project/dpdk/patch/20221213091837.87953-1-david.marchand@redhat.com/	a8ca8ed net/i40e: revert link status check on device start

I have already reverted those 3 backports on 21.11 branch so this is not 
needed.

> 	Pathc2: https://patchwork.dpdk.org/project/dpdk/patch/20230306121853.27547-1-simei.su@intel.com/	82fcf20 net/i40e: fix maximum frame size configuration
> 

That is the v7 of this v6 with revert and fix split, so same one being 
discussed above.

> Best regards,
> Yu Jiang
> 
>> thanks,
>> Kevin.
>>
>>> After reverting the original patch and 2 fixes, I'm a bit reluctant to
>>> take more fixes without some form of regression testing in place.
>>>
>>> thanks,
>>> Kevin.
>>>
>>>>>
>>>>> Reported-by: David Marchand <david.marchand@redhat.com>
>>>>> Signed-off-by: Simei Su <simei.su@intel.com>
>>>>
>>>> Acked-by: Qi Zhang <qi.z.zhang@intel.com>
>>>>
>>>> Applied to dpdk-next-net-intel.
>>>>
>>>> Thanks
>>>> Qi
>>>>
>>>
>