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authorJohan Hovold <johan+linaro@kernel.org>2025-06-04 17:34:56 +0300
committerJeff Johnson <jeff.johnson@oss.qualcomm.com>2025-06-27 02:10:47 +0300
commit6efa0df54022c6c9fd4d294b87622c7fcdc418c8 (patch)
treef45518221ee0278b6920f97f13843913838a288f
parent4aba95fb1faed7fe7f6e1edfb60c333e0275dfc1 (diff)
downloadlinux-6efa0df54022c6c9fd4d294b87622c7fcdc418c8.tar.xz
wifi: ath11k: fix source ring-buffer corruption
Add the missing memory barrier to make sure that LMAC source ring descriptors are written before updating the head pointer to avoid passing stale data to the firmware on weakly ordered architectures like aarch64. Note that non-LMAC rings use MMIO write accessors which have the required write memory barrier. Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41 Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices") Cc: stable@vger.kernel.org # 5.6 Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Reviewed-by: Baochen Qiang <quic_bqiang@quicinc.com> Link: https://patch.msgid.link/20250604143457.26032-5-johan+linaro@kernel.org Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
-rw-r--r--drivers/net/wireless/ath/ath11k/hal.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/net/wireless/ath/ath11k/hal.c b/drivers/net/wireless/ath/ath11k/hal.c
index 4a3bdacc5769..28f94c36d304 100644
--- a/drivers/net/wireless/ath/ath11k/hal.c
+++ b/drivers/net/wireless/ath/ath11k/hal.c
@@ -864,7 +864,11 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng)
if (srng->ring_dir == HAL_SRNG_DIR_SRC) {
srng->u.src_ring.last_tp =
*(volatile u32 *)srng->u.src_ring.tp_addr;
- *srng->u.src_ring.hp_addr = srng->u.src_ring.hp;
+ /* Make sure descriptor is written before updating the
+ * head pointer.
+ */
+ dma_wmb();
+ WRITE_ONCE(*srng->u.src_ring.hp_addr, srng->u.src_ring.hp);
} else {
srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr;
*srng->u.dst_ring.tp_addr = srng->u.dst_ring.tp;
@@ -873,6 +877,10 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng)
if (srng->ring_dir == HAL_SRNG_DIR_SRC) {
srng->u.src_ring.last_tp =
*(volatile u32 *)srng->u.src_ring.tp_addr;
+ /* Assume implementation use an MMIO write accessor
+ * which has the required wmb() so that the descriptor
+ * is written before the updating the head pointer.
+ */
ath11k_hif_write32(ab,
(unsigned long)srng->u.src_ring.hp_addr -
(unsigned long)ab->mem,