Re: [PATCH v2] ath11k: fix peer resolution on rx path when peer_id=0

[Baochen Qiang]

On 4/15/2026 7:39 PM, Matthew Leach wrote:
> It has been observed that on certain chipsets a peer can be assigned
> peer_id=0. For reception of standard MPDUs this is fine as
> ath11k_dp_rx_h_find_peer() has a fallback case where it locates the peer
> based upon the source mac address.
> 
> However, on an aggregated link, reception of AMSDUs results in the peer
> not being resolved for the second (any any subsequent) sub-MSDUs due to
> the peer_id guard in ath11k_dp_rx_h_find_peer(). This causes the

it is necessary to point out that the mac address based fallback does not work for those
sub-MSDUs as well, since the mpdu_start descriptor from where mac address is obtained is
not populated by hardware.

> encryption type of the frame to be set to an incorrect value, resulting
> in the sub-MSDUs being dropped by ieee80211.
> 
> ath11k_pci 0000:03:00.0: data rx skb 000000002f4b704d len 1534 peer xx:xx:xx:xx:xx:xx 0 ucast sn 3063 he160 rate_idx 9 vht_nss 2 freq 5240 band 1 flag 0x40d1a fcs-err 0 mic-err 0 amsdu-more 0 peer_id 0 first_msdu 1 last_msdu 0
> ath11k_pci 0000:03:00.0: data rx skb 0000000038acd580 len 1534 peer (null) 0 ucast sn 3063 he160 rate_idx 9 vht_nss 2 freq 5240 band 1 flag 0x40d00 fcs-err 0 mic-err 0 amsdu-more 0 peer_id 0 first_msdu 0 last_msdu 1
> 
> This patch removes the null peer_id check in ath11k_dp_rx_h_find_peer(),
> allowing peer's with an assigned ID of 0 to be resolved.
> 
> Signed-off-by: Matthew Leach <matthew.leach@xxxxxxxxxxxxx>
> ---
> Changes in v2:
> 
> - Since peer_id=0 is a valid condition on some chips, remove the guard
>   that prevented the peer lookup.
> - Link to v1: https://patch.msgid.link/20260326-ath11k-null-peerid-workaround-v1-1-0c2fd53202f8@xxxxxxxxxxxxx
> 
> To: Jeff Johnson <jjohnson@xxxxxxxxxx>
> Cc: linux-wireless@xxxxxxxxxxxxxxx
> Cc: ath11k@xxxxxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> ---
>  drivers/net/wireless/ath/ath11k/dp_rx.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c
> index 49d959b2e148..ff2c78a4e5f3 100644
> --- a/drivers/net/wireless/ath/ath11k/dp_rx.c
> +++ b/drivers/net/wireless/ath/ath11k/dp_rx.c
> @@ -2215,8 +2215,7 @@ ath11k_dp_rx_h_find_peer(struct ath11k_base *ab, struct sk_buff *msdu)
>  
>  	lockdep_assert_held(&ab->base_lock);
>  
> -	if (rxcb->peer_id)
> -		peer = ath11k_peer_find_by_id(ab, rxcb->peer_id);
> +	peer = ath11k_peer_find_by_id(ab, rxcb->peer_id);
>  
>  	if (peer)
>  		return peer;

the other instance in ath11k_hal_rx_parse_mon_status_tlv() is missed.

> 
> ---
> base-commit: f338e77383789c0cae23ca3d48adcc5e9e137e3c
> change-id: 20260326-ath11k-null-peerid-workaround-625a129781b1
> 
> Best regards,
> --  
> Matt
>