On Mon, Nov 25, 2019 at 12:42:44PM +0100, Paolo Abeni wrote:

I think it would be nice moving the iwlwifi driver to full/plain NAPI
mode. The interrupt handler could keep processing extra work as it does
now and queue real pkts on some internal queue, and than schedule the
relevant napi, which in turn could process such queue in the napi poll
method. Likely I missed tons of details and/or oversimplified it...

It must have something to do with iwlwifi (as if we needed more 
evidence). I just booted a different variant of the Dell XPS 9370 which 
has Qualcomm Wi-Fi [168c:003e] (ath10k_pci.ko), instead of Intel Wi-Fi, 
from the same USB SSD as before, and it has no issues whatsoever.

My regression report quickly blown up to be way over my head in terms of 
understanding, but I will keep monitoring the discussions and try to 
learn from it. Everybody, please keep me CC'd into any further 
communications with driver teams, as I am genuinely interested in the 
journey and the outcome.

Cheers,

Paolo

Cheers,
Nicholas