Re: [PATCH v4] wifi: ath11k: fix peer resolution on rx path when peer_id=0

[Praneesh P <praneesh.p@oss.qualcomm.com>]

On 4/24/2026 3:20 PM, Matthew Leach wrote:
> It has been observed that on certain chipsets a peer can be assigned
> peer_id=0. For reception of non-aggregated 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. On an aggregated link, the mpdu_start
> header is only populated by hardware on the first sub-MSDU. This causes
> the peer resolution to be skipped for the subsequent MSDUs and the
> encryption type of these frames to be set to an incorrect value,
> resulting in these 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
>
> Remove the null peer_id checks in ath11k_dp_rx_h_find_peer() and
> ath11k_hal_rx_parse_mon_status_tlv(), allowing peers with an assigned ID
> of 0 to be resolved.
>
> Fixes: 2167fa606c0f ("ath11k: Add support for RX decapsulation offload")
> Tested-on: QCA2066 hw2.1 PCI WLAN.HSP.1.1-03926.13-QCAHSPSWPL_V2_SILICONZ_CE-2.52297.9
> Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
> Signed-off-by: Matthew Leach <matthew.leach@collabora.com>
> ---
> Changes in v4:
> - Prefix subsystem with 'wifi:'.
> - Added the 'Tested-by' and 'Fixes' trailers.
> - Link to v3: https://patch.msgid.link/20260417-ath11k-null-peerid-workaround-v3-1-d04302284486@collabora.com
>
> Changes in v3:
> - Clarified that the mpdu_start header isn't populated by the h/w for
>    all sub-MSDUs in the commit message.
> - Fix second null-peer check in ath11k_hal_rx_parse_mon_status_tlv().
> - Link to v2: https://patch.msgid.link/20260415-ath11k-null-peerid-workaround-v2-1-2abae3bbac16@collabora.com
>
> 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@collabora.com
>
> To: Jeff Johnson <jjohnson@kernel.org>
> Cc: linux-wireless@vger.kernel.org
> Cc: ath11k@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> ---
>   drivers/net/wireless/ath/ath11k/dp_rx.c  | 3 +--
>   drivers/net/wireless/ath/ath11k/hal_rx.c | 5 +----
>   2 files changed, 2 insertions(+), 6 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;
> diff --git a/drivers/net/wireless/ath/ath11k/hal_rx.c b/drivers/net/wireless/ath/ath11k/hal_rx.c
> index 753bd93f0212..51e0840bc0d1 100644
> --- a/drivers/net/wireless/ath/ath11k/hal_rx.c
> +++ b/drivers/net/wireless/ath/ath11k/hal_rx.c
> @@ -1467,11 +1467,8 @@ ath11k_hal_rx_parse_mon_status_tlv(struct ath11k_base *ab,
>   	case HAL_RX_MPDU_START: {
>   		struct hal_rx_mpdu_info *mpdu_info =
>   				(struct hal_rx_mpdu_info *)tlv_data;
> -		u16 peer_id;
>   
> -		peer_id = ath11k_hal_rx_mpduinfo_get_peerid(ab, mpdu_info);
> -		if (peer_id)
> -			ppdu_info->peer_id = peer_id;
> +		ppdu_info->peer_id = ath11k_hal_rx_mpduinfo_get_peerid(ab, mpdu_info);
>   		break;
>   	}
>   	case HAL_RXPCU_PPDU_END_INFO: {
>
> ---
> base-commit: f338e77383789c0cae23ca3d48adcc5e9e137e3c
> change-id: 20260326-ath11k-null-peerid-workaround-625a129781b1
>
> Best regards,
> --
> Matt
Reviewed-by: P Praneesh <praneesh.p@oss.qualcomm.com>