[PATCH] wifi: ath12k: fix DMA unmap warning on NULL DMA address

[Kalle Valo]

Baochen Qiang <quic_bqiang at quicinc.com> wrote:

> In ath12k_dp_tx(), if we reach fail_dma_unmap due to some errors,
> current code does DMA unmap unconditionally on skb_cb->paddr_ext_desc.
> However, skb_cb->paddr_ext_desc may be NULL and thus we get below
> warning:
> 
> kernel: [ 8887.076212] WARNING: CPU: 3 PID: 0 at drivers/iommu/dma-iommu.c:1077 iommu_dma_unmap_page+0x79/0x90
> 
> Fix it by checking skb_cb->paddr_ext_desc before unmap it.
> 
> Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0-03427-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.15378.4
> 
> Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
> Signed-off-by: Baochen Qiang <quic_bqiang at quicinc.com>
> Acked-by: Jeff Johnson <quic_jjohnson at quicinc.com>
> Signed-off-by: Kalle Valo <quic_kvalo at quicinc.com>

Patch applied to ath-next branch of ath.git, thanks.

9ae8c496d211 wifi: ath12k: fix DMA unmap warning on NULL DMA address

-- 
https://patchwork.kernel.org/project/linux-wireless/patch/20230830021131.5610-1-quic_bqiang@quicinc.com/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches