[PATCH 6.12 161/169] wifi: ath11k: fix RCU stall while reaping monitor destination ring

Greg Kroah-Hartman
2026-01-28T15:49:34Z

From: P Praneesh <quic_ppranees@quicinc.com>

[ Upstream commit 16c6c35c03ea73054a1f6d3302a4ce4a331b427d ]

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>
Signed-off-by: Li hongliang <1468888505@139.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/wireless/ath/ath11k/dp_rx.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/net/wireless/ath/ath11k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_rx.c
@@ -4777,7 +4777,7 @@ ath11k_dp_rx_mon_mpdu_pop(struct ath11k
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) {
@@ -5404,7 +5404,7 @@ ath11k_dp_rx_full_mon_mpdu_pop(struct at
"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);