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Date:   Wed, 13 May 2020 13:48:27 -0400
From:   Marco Fonseca <marco@tampabay.rr.com>
To:     linux-wireless@vger.kernel.org
Subject: iwlwifi: 8265: unexpected LLC packets TX'ed in monitor mode
Message-ID: <20200513174827.3o7odouinuirou62@192.168.1.10>
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Hello,

While in monitor mode, the 8265 will periodically transmit gratuitous
LLC packets.  In this mode, I would expect the wifi chipset to not
transmit any packets at all (unless packet injection is being used).

This behavior can be observed by a second wifi device in monitor mode.
A display filter on wireshark/tshark of 'llc' makes these easy to spot.

It seems these packets only get produced in presence of a few APs
and/or STAs but I'm not sure of the exact cause.  I don't see the LLC
packets on very quiet channels.

Other Details
-------------

wifi chipset:
  Intel(R) Dual Band Wireless AC 8265, REV=0x230

kernel:
  4.9.11 kernel

backports driver:
  iwlwifi-stack-public:release/core33:6653:327571a8

  I can use other backports versions if needed, but this was the
  version called out in:
  https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi/core_release

Firmware:
36.952d9faa.0


Thank you,

Marco Fonseca