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

[Matthew Leach]

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
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 at 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 at kernel.org>
Cc: linux-wireless at vger.kernel.org
Cc: ath11k at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
---
 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;

---
base-commit: f338e77383789c0cae23ca3d48adcc5e9e137e3c
change-id: 20260326-ath11k-null-peerid-workaround-625a129781b1

Best regards,
--  
Matt