wifi: ath11k: fix RCU stall while reaping monitor destination ring

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@quicinc.com>
Signed-off-by: Kang Yang <quic_kangyang@quicinc.com>
Acked-by: Kalle Valo <kvalo@kernel.org>
Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://patch.msgid.link/20241219110531.2096-2-quic_kangyang@quicinc.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>

diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c
index 640d617a585afcaf55f5cc277fde606c0ac1df7c..d010b25b8503f183eb54eb4f0b598f85a36ee30f 100644 (file)
--- a/drivers/net/wireless/ath/ath11k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_rx.c
@@ -4772,7 +4772,7 @@ u32 ath11k_dp_rx_mon_mpdu_pop(struct ath11k *ar, int mac_id,
                        if (!msdu) {
                                ath11k_dbg(ar->ab, ATH11K_DBG_DATA,
                                           "msdu_pop: invalid buf_id %d\n", buf_id);
-                               break;
+                               goto next_msdu;
                        }
                        rxcb = ATH11K_SKB_RXCB(msdu);
                        if (!rxcb->unmapped) {
@@ -5399,7 +5399,7 @@ ath11k_dp_rx_full_mon_mpdu_pop(struct ath11k *ar,
                                           "full mon msdu_pop: invalid buf_id %d\n",
                                            buf_id);
                                spin_unlock_bh(&rx_ring->idr_lock);
-                               break;
+                               goto next_msdu;
                        }
                        idr_remove(&rx_ring->bufs_idr, buf_id);
                        spin_unlock_bh(&rx_ring->idr_lock);