Re: invalid vht params rate 1920 100kbps nss 2 mcs 9

[Kalle Valo <kvalo@kernel.org>]

+ baochen

James Prestwood <prestwoj@gmail.com> writes:

> Hi Kalle,
>
> On 6/17/24 8:27 AM, Kalle Valo wrote:
>> James Prestwood <prestwoj@gmail.com> writes:
>>
>>> Hi Paul,
>>>
>>> On 6/16/24 6:10 AM, Paul Menzel wrote:
>>>> Dear Linux folks,
>>>>
>>>>
>>>> Linux 6.10-rc3 (commit a3e18a540541) logged the warning below when
>>>> connecting to a public WiFi:
>>>>
>>>>      ath10k_pci 0000:3a:00.0: invalid vht params rate 1920 100kbps
>>>> nss 2 mcs 9
>>> This has been reported/discussed [1]. It was hinted that there was a
>>> firmware fix for this, but none that I tried got rid of it. I got fed
>>> up enough with the logs filling up with this I patched our kernel to
>>> remove the warning. AFAICT it appears benign (?). Removing the warning
>>> was purely "cosmetic" so other devs stopped complaining about it :)
>>>
>>> [1] https://www.mail-archive.com/ath10k@lists.infradead.org/msg13406.html
>> More reliable link to the discussion:
>>
>> https://lore.kernel.org/ath10k/76a816d983e6c4d636311738396f97971b5523fb.1612915444.git.skhan@linuxfoundation.org/
>>
>> I think we should add this workaround I mentioned in 2021:
>>
>>     "If the firmware still keeps sending invalid rates we should add a
>>      specific check to ignore the known invalid values, but not all of
>>      them."
>>
>>     https://lore.kernel.org/ath10k/87h7mktjgi.fsf@codeaurora.org/
>>
>> I guess that would be mcs == 7 and rate == 1440?
>
> I think its more than this combination (Paul's are different). 

Good point.

> So how many combinations are we willing to add here? Seems like that
> could get out of hand if there are more than a few invalid
> combinations. 

Yeah, but there haven't been that many different values reported yet,
right? And I expect that ath10k user base will just get smaller in the
future so the chances are that we will get less reports.

> Would we also want to restrict the workaround to specific
> hardware/firmware?

Good idea, limiting per hardware would be simple to implement using
hw_params. Of course we could even limit this per firmware version using
enum ath10k_fw_features, but not sure if that's worth all the extra work.

Baochen, do you know more about this firmware bug? Any suggestions?

-- 
https://patchwork.kernel.org/project/linux-wireless/list/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches