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The skb is empty at that point, so skb_pull() rejects every positive delta and leaves the data pointer unchanged. Use skb_reserve() while the skb is empty. The existing extra allocation space leaves at least DP_RX_BUFFER_SIZE bytes of DMA tailroom after the reservation. Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices") Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.9.0.1-02146-QCAHKSWPL_SILICONZ-1 Signed-off-by: Mark Ruvald Pedersen --- diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c index 33425707c..e4ea0c216 100644 --- a/drivers/net/wireless/ath/ath11k/dp_rx.c +++ b/drivers/net/wireless/ath/ath11k/dp_rx.c @@ -378,7 +378,7 @@ int ath11k_dp_rxbufs_replenish(struct ath11k_base *ab, int mac_id, if (!IS_ALIGNED((unsigned long)skb->data, DP_RX_BUFFER_ALIGN_SIZE)) { - skb_pull(skb, - PTR_ALIGN(skb->data, DP_RX_BUFFER_ALIGN_SIZE) - - skb->data); + skb_reserve(skb, + PTR_ALIGN(skb->data, DP_RX_BUFFER_ALIGN_SIZE) - + skb->data); } @@ -2875,7 +2875,7 @@ static struct sk_buff *ath11k_dp_rx_alloc_mon_status_buf(struct ath11k_base *ab, if (!IS_ALIGNED((unsigned long)skb->data, DP_RX_BUFFER_ALIGN_SIZE)) { - skb_pull(skb, PTR_ALIGN(skb->data, DP_RX_BUFFER_ALIGN_SIZE) - + skb_reserve(skb, PTR_ALIGN(skb->data, DP_RX_BUFFER_ALIGN_SIZE) - skb->data); }