Re: [PATCH net v2] eth: fbnic: Keep real queue counts synchronized

["Björn Töpel" <bjorn@kernel.org>]

Breno!

Thanks for having a look!

Breno Leitao <leitao@debian.org> writes:

> Hello Björn,
>
> On Thu, Sep 24, 2026 at 09:18:15PM +0200, Björn Töpel wrote:
>> If resume gets fewer vectors than the configured
>> layout needs, fail with -ENOSPC rather than silently change the queue
>> configuration and its bindings. The netdev then stays detached until a
>> later recovery or a device reprobe.
>
> I am a bit surprised that I is better to get the device permanetly
> disconnected other than just getting it running with fewer queues on
> resume.

What's the queue selection policy?

 - Memory providers and AF_XDP                                                                          
 - RSS indirection and contexts                                                                         
 - ntuple rules                                                                                         
 - Queue leases                                                                                         

> What is reprobing it later?

Nothing does it automatically. The netdev stays detached until a later
suspend/resume gets enough vectors, or until someone rebinds the driver.
A rebind resets the channels and drops the memory-provider bindings
anyway *shrug*.

This only happens when resume gets fewer MSI-X vectors than the
configured layout uses, for example when CPUs were offlined after the
channels were set.

...*is* this a real issue, or mostly theoretical?


Enjoy the weekend!
Björn