Christian 'Ansuel' Marangi <ansuelsmth@xxxxxxxxx> wrote:
> This patch try to fix the following error.
>
> Wed Jun 1 22:19:30 2022 kern.warn kernel: [ 119.561227] ath11k c000000.wifi: peer already added vdev id 0 req, vdev id 1 present
> Wed Jun 1 22:19:30 2022 kern.warn kernel: [ 119.561282] ath11k c000000.wifi: Failed to add peer: 28:c2:1f:xx:xx:xx for VDEV: 0
> Wed Jun 1 22:19:30 2022 kern.warn kernel: [ 119.568053] ath11k c000000.wifi: Failed to add station: 28:c2:1f:xx:xx:xx for VDEV: 0
> Wed Jun 1 22:19:31 2022 daemon.notice hostapd: wlan2: STA 28:c2:1f:xx:xx:xx IEEE 802.11: Could not add STA to kernel driver
> Wed Jun 1 22:19:31 2022 daemon.notice hostapd: wlan2: STA 28:c2:1f:xx:xx:xx IEEE 802.11: did not acknowledge authentication response
> Wed Jun 1 22:19:31 2022 daemon.notice hostapd: wlan1: AP-STA-DISCONNECTED 28:c2:1f:xx:xx:xx
> Wed Jun 1 22:19:31 2022 daemon.info hostapd: wlan1: STA 28:c2:1f:xx:xx:xx IEEE 802.11: disassociated due to inactivity
> Wed Jun 1 22:19:32 2022 daemon.info hostapd: wlan1: STA 28:c2:1f:xx:xx:xx IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
>
> To repro this:
> - Have 2 Wifi with the same bssid and pass on different band (2.4 and
> 5GHz)
> - Enable 802.11r Fast Transaction with same mobility domain
> - FT Protocol: FT over the Air
> From a openwrt system issue the command (with the correct mac)
> ubus call hostapd.wlan1 wnm_disassoc_imminent '{"addr":"28:C2:1F:xx:xx:xx"}'
> Notice the log printing the errors.
>
> The cause of this error has been investigated and we found that this is
> related to the WiFi Fast Transaction feature. We observed that this is
> triggered when the router tells the device to change band. In this case
> the device first auth to the other band and then the disconnect path
> from the prev band is triggered.
> This is problematic with the current rhash implementation since the
> addrs is used as key and the logic of "adding first, delete later"
> conflicts with the rhash logic.
> In fact peer addition will fail since the peer is already added and with
> that fixed a peer deletion will cause unitended effect by removing the
> peer just added.
>
> Current solution to this is to add additional logic to the peer delete,
> make sure we are deleting the correct peer taken from the rhash
> table (and fallback to the peer list) and for the peer add logic delete
> the peer entry for the rhash list before adding the new one (counting as
> an error only when a peer with the same vlan_id is asked to be added).
>
> With this change, a sta can correctly transition from 2.4GHz and 5GHZ
> with no drop and no error are printed.
>
> Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.5.0.1-01208-QCAHKSWPL_SILICONZ-1
>
> Fixes: 7b0c70d92a43 ("ath11k: Add peer rhash table support")
> Signed-off-by: Christian 'Ansuel' Marangi <ansuelsmth@xxxxxxxxx>
> Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx>
Patch applied to ath-next branch of ath.git, thanks.
d673cb6fe6c0 wifi: ath11k: fix peer addition/deletion error on sta band migration
--
https://patchwork.kernel.org/project/linux-wireless/patch/20220603164559.27769-1-ansuelsmth@xxxxxxxxx/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
