Re: [PATCH net v2] net: Don't allow disabling napi kthread mode while napi instances are disabled

[Maxime Chevallier <maxime.chevallier@bootlin.com>]

Hi Paolo,

On 10/12/26 18:31, Paolo Abeni wrote:
> On 10/8/26 12:19, Maxime Chevallier wrote:
>> On 10/8/26 04:11, netdev-bot+sashiko@kernel.org wrote:
>>> Would it be better to handle disabled NAPIs in the stop path itself,
>>> napi_stop_kthread() or napi_set_threaded(), rather than only guarding the
>>> explicit disable branch?
>>
>> Hmmm maybe yes
> My personal take is that the complexity of addressing the issue for good at
> the core level sounds like a good argument to fix this at the device level,
> one device at the time, as needed.

Fixing that in drivers isn't enough however. The visible problem of hanging while
disabling threaded mode if the interface is down would be addressed, but not the
corner cases such as "disabling threaded mode while changing the MTU" for example.

And this is a lot harder to test :(

> 
> Otherwise I'll probably got for the suggested path above.

My brain is becoming a bit more operational now that the conference flu I caught
last week is healing, I'll spin another round see if I can get that addressed.

Maxime