[PATCH v4 1/2] wifi: ath11k: fix RCU stall while reaping monitor destination ring

[Vasanthakumar Thiagarajan]

On 12/19/2024 4:35 PM, Kang Yang wrote:
> From: P Praneesh <quic_ppranees at quicinc.com>
> 
> While processing the monitor destination ring, MSDUs are reaped from the
> link descriptor based on the corresponding buf_id.
> 
> However, sometimes the driver cannot obtain a valid buffer corresponding
> to the buf_id received from the hardware. This causes an infinite loop
> in the destination processing, resulting in a kernel crash.
> 
> kernel log:
> ath11k_pci 0000:58:00.0: data msdu_pop: invalid buf_id 309
> ath11k_pci 0000:58:00.0: data dp_rx_monitor_link_desc_return failed
> ath11k_pci 0000:58:00.0: data msdu_pop: invalid buf_id 309
> ath11k_pci 0000:58:00.0: data dp_rx_monitor_link_desc_return failed
> 
> Fix this by skipping the problematic buf_id and reaping the next entry,
> replacing the break with the next MSDU processing.
> 
> Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.30
> Tested-on: QCN9074 hw1.0 PCI WLAN.HK.2.7.0.1-01744-QCAHKSWPL_SILICONZ-1
> 
> Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices")
> Signed-off-by: P Praneesh <quic_ppranees at quicinc.com>
> Signed-off-by: Kang Yang <quic_kangyang at quicinc.com>

Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan at oss.qualcomm.com>