Re: [Intel-wired-lan] [iwl-next v4 2/2] igc: Link queues to NAPI instances

[Jacob Keller <jacob.e.keller@intel.com>]

On 10/28/2024 9:00 AM, Joe Damato wrote:
> 
> I see, so it looks like there is:
>    - resume
>    - runtime_resume
> 
> The bug I am reintroducing is runtime_resume already holding RTNL
> before my added call to rtnl_lock.
> 
> OK.
> 
> Does resume also hold rtnl before the driver's igc_resume is called?
> I am asking because I don't know much about how PM works.
> 
> If resume does not hold RTNL (but runtime resume does, as the bug
> you pointed out shows), it seems like a wrapper can be added to tell
> the code whether rtnl should be held or not based on which resume is
> happening.
> 
> Does anyone know if: resume (not runtime_resume) already holds RTNL?
> I'll try to take a look and see, but I am not very familiar with PM.

I believe the resume doesn't hold RTNL, as its part of the core device
code, which is not networking specific. It shouldn't be acquiring RTNL
since that is a network specific lock.

I believe the code you posted as v5 should resolve this, and makes sense
to me.

Thanks for digging into this :)

-Jake