[Intel-wired-lan] [PATCH] i40e: fix the wrong PTP frequency calculation

[Tony Nguyen]

On 9/25/2023 12:55 AM, Yajun Deng wrote:
> 
> On 2023/6/28 04:20, Jacob Keller wrote:
>>
>> On 6/26/2023 7:26 PM, Yajun Deng wrote:
>>> The new adjustment should be based on the base frequency, not the
>>> I40E_PTP_40GB_INCVAL in i40e_ptp_adjfine().
>>>
>>> This issue was introduced in commit 3626a690b717 ("i40e: use
>>> mul_u64_u64_div_u64 for PTP frequency calculation"), and was fixed in
>>> commit 1060707e3809 ("ptp: introduce helpers to adjust by scaled
>>> parts per million"). However the latter is a new feature and hasn't been
>>> backported to the stable releases.
>>>
>>> This issue affects both v6.0 and v6.1 versions, and the v6.1 version is
>>> an LTS version.
>>>

...

>>
>> Thanks for finding and fixing this mistake. I think its the simplest fix
>> to get into the stable kernel that are broken, since taking the
>> adjust_by_scaled_ppm version would require additional patches.
>>
>> Reviewed-by: Jacob Keller <jacob.e.keller at intel.com>
>>
> Kindly ping...

As this patch looks to be for stable, you need to follow the process for 
that. I believe your situation would fall into option 3:
https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html#option-3

Thanks,
Tony