* [PATCH v3 1/4] wifi: ath12k: fix dest ring-buffer corruption
2025-06-17 8:43 [PATCH v3 0/4] wifi: ath12k: fix dest ring-buffer corruption Johan Hovold
@ 2025-06-17 8:43 ` Johan Hovold
2025-06-25 1:53 ` Baochen Qiang
2025-06-17 8:44 ` [PATCH v3 2/4] wifi: ath12k: use plain access for descriptor length Johan Hovold
` (3 subsequent siblings)
4 siblings, 1 reply; 10+ messages in thread
From: Johan Hovold @ 2025-06-17 8:43 UTC (permalink / raw)
To: Jeff Johnson
Cc: Miaoqing Pan, Remi Pommarel, Baochen Qiang, linux-wireless,
ath12k, linux-kernel, Johan Hovold, stable
Add the missing memory barrier to make sure that destination ring
descriptors are read after the head pointers to avoid using stale data
on weakly ordered architectures like aarch64.
The barrier is added to the ath12k_hal_srng_access_begin() helper for
symmetry with follow-on fixes for source ring buffer corruption which
will add barriers to ath12k_hal_srng_access_end().
Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
Cc: stable@vger.kernel.org # 6.3
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
drivers/net/wireless/ath/ath12k/ce.c | 3 ---
drivers/net/wireless/ath/ath12k/hal.c | 17 ++++++++++++++---
2 files changed, 14 insertions(+), 6 deletions(-)
diff --git a/drivers/net/wireless/ath/ath12k/ce.c b/drivers/net/wireless/ath/ath12k/ce.c
index 3f3439262cf4..f7c15b547504 100644
--- a/drivers/net/wireless/ath/ath12k/ce.c
+++ b/drivers/net/wireless/ath/ath12k/ce.c
@@ -433,9 +433,6 @@ static int ath12k_ce_completed_recv_next(struct ath12k_ce_pipe *pipe,
goto err;
}
- /* Make sure descriptor is read after the head pointer. */
- dma_rmb();
-
*nbytes = ath12k_hal_ce_dst_status_get_length(desc);
*skb = pipe->dest_ring->skb[sw_index];
diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c
index a301898e5849..f8bd3837b9dc 100644
--- a/drivers/net/wireless/ath/ath12k/hal.c
+++ b/drivers/net/wireless/ath/ath12k/hal.c
@@ -2143,13 +2143,24 @@ void *ath12k_hal_srng_src_get_next_reaped(struct ath12k_base *ab,
void ath12k_hal_srng_access_begin(struct ath12k_base *ab, struct hal_srng *srng)
{
+ u32 hp;
+
lockdep_assert_held(&srng->lock);
- if (srng->ring_dir == HAL_SRNG_DIR_SRC)
+ if (srng->ring_dir == HAL_SRNG_DIR_SRC) {
srng->u.src_ring.cached_tp =
*(volatile u32 *)srng->u.src_ring.tp_addr;
- else
- srng->u.dst_ring.cached_hp = READ_ONCE(*srng->u.dst_ring.hp_addr);
+ } else {
+ hp = READ_ONCE(*srng->u.dst_ring.hp_addr);
+
+ if (hp != srng->u.dst_ring.cached_hp) {
+ srng->u.dst_ring.cached_hp = hp;
+ /* Make sure descriptor is read after the head
+ * pointer.
+ */
+ dma_rmb();
+ }
+ }
}
/* Update cached ring head/tail pointers to HW. ath12k_hal_srng_access_begin()
--
2.49.0
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH v3 1/4] wifi: ath12k: fix dest ring-buffer corruption
2025-06-17 8:43 ` [PATCH v3 1/4] " Johan Hovold
@ 2025-06-25 1:53 ` Baochen Qiang
0 siblings, 0 replies; 10+ messages in thread
From: Baochen Qiang @ 2025-06-25 1:53 UTC (permalink / raw)
To: Johan Hovold, Jeff Johnson
Cc: Miaoqing Pan, Remi Pommarel, linux-wireless, ath12k, linux-kernel,
stable
On 6/17/2025 4:43 PM, Johan Hovold wrote:
> Add the missing memory barrier to make sure that destination ring
> descriptors are read after the head pointers to avoid using stale data
> on weakly ordered architectures like aarch64.
>
> The barrier is added to the ath12k_hal_srng_access_begin() helper for
> symmetry with follow-on fixes for source ring buffer corruption which
> will add barriers to ath12k_hal_srng_access_end().
>
> Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
>
> Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
> Cc: stable@vger.kernel.org # 6.3
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---
> drivers/net/wireless/ath/ath12k/ce.c | 3 ---
> drivers/net/wireless/ath/ath12k/hal.c | 17 ++++++++++++++---
> 2 files changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/ath12k/ce.c b/drivers/net/wireless/ath/ath12k/ce.c
> index 3f3439262cf4..f7c15b547504 100644
> --- a/drivers/net/wireless/ath/ath12k/ce.c
> +++ b/drivers/net/wireless/ath/ath12k/ce.c
> @@ -433,9 +433,6 @@ static int ath12k_ce_completed_recv_next(struct ath12k_ce_pipe *pipe,
> goto err;
> }
>
> - /* Make sure descriptor is read after the head pointer. */
> - dma_rmb();
> -
> *nbytes = ath12k_hal_ce_dst_status_get_length(desc);
>
> *skb = pipe->dest_ring->skb[sw_index];
> diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c
> index a301898e5849..f8bd3837b9dc 100644
> --- a/drivers/net/wireless/ath/ath12k/hal.c
> +++ b/drivers/net/wireless/ath/ath12k/hal.c
> @@ -2143,13 +2143,24 @@ void *ath12k_hal_srng_src_get_next_reaped(struct ath12k_base *ab,
>
> void ath12k_hal_srng_access_begin(struct ath12k_base *ab, struct hal_srng *srng)
> {
> + u32 hp;
> +
> lockdep_assert_held(&srng->lock);
>
> - if (srng->ring_dir == HAL_SRNG_DIR_SRC)
> + if (srng->ring_dir == HAL_SRNG_DIR_SRC) {
> srng->u.src_ring.cached_tp =
> *(volatile u32 *)srng->u.src_ring.tp_addr;
> - else
> - srng->u.dst_ring.cached_hp = READ_ONCE(*srng->u.dst_ring.hp_addr);
> + } else {
> + hp = READ_ONCE(*srng->u.dst_ring.hp_addr);
> +
> + if (hp != srng->u.dst_ring.cached_hp) {
> + srng->u.dst_ring.cached_hp = hp;
> + /* Make sure descriptor is read after the head
> + * pointer.
> + */
> + dma_rmb();
> + }
> + }
> }
>
> /* Update cached ring head/tail pointers to HW. ath12k_hal_srng_access_begin()
Reviewed-by: Baochen Qiang <quic_bqiang@quicinc.com>
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH v3 2/4] wifi: ath12k: use plain access for descriptor length
2025-06-17 8:43 [PATCH v3 0/4] wifi: ath12k: fix dest ring-buffer corruption Johan Hovold
2025-06-17 8:43 ` [PATCH v3 1/4] " Johan Hovold
@ 2025-06-17 8:44 ` Johan Hovold
2025-06-25 1:53 ` Baochen Qiang
2025-06-17 8:44 ` [PATCH v3 3/4] wifi: ath12k: fix source ring-buffer corruption Johan Hovold
` (2 subsequent siblings)
4 siblings, 1 reply; 10+ messages in thread
From: Johan Hovold @ 2025-06-17 8:44 UTC (permalink / raw)
To: Jeff Johnson
Cc: Miaoqing Pan, Remi Pommarel, Baochen Qiang, linux-wireless,
ath12k, linux-kernel, Johan Hovold
The read memory barrier added by commit 6b67d2cf14ea ("wifi: ath12k: fix
ring-buffer corruption") is enough to guarantee ordering also for plain
descriptor accesses if the length helper is ever inlined so drop the
unnecessary READ_ONCE().
Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
drivers/net/wireless/ath/ath12k/hal.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c
index f8bd3837b9dc..726969cfcaec 100644
--- a/drivers/net/wireless/ath/ath12k/hal.c
+++ b/drivers/net/wireless/ath/ath12k/hal.c
@@ -1950,7 +1950,7 @@ u32 ath12k_hal_ce_dst_status_get_length(struct hal_ce_srng_dst_status_desc *desc
{
u32 len;
- len = le32_get_bits(READ_ONCE(desc->flags), HAL_CE_DST_STATUS_DESC_FLAGS_LEN);
+ len = le32_get_bits(desc->flags, HAL_CE_DST_STATUS_DESC_FLAGS_LEN);
desc->flags &= ~cpu_to_le32(HAL_CE_DST_STATUS_DESC_FLAGS_LEN);
return len;
--
2.49.0
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH v3 2/4] wifi: ath12k: use plain access for descriptor length
2025-06-17 8:44 ` [PATCH v3 2/4] wifi: ath12k: use plain access for descriptor length Johan Hovold
@ 2025-06-25 1:53 ` Baochen Qiang
0 siblings, 0 replies; 10+ messages in thread
From: Baochen Qiang @ 2025-06-25 1:53 UTC (permalink / raw)
To: Johan Hovold, Jeff Johnson
Cc: Miaoqing Pan, Remi Pommarel, linux-wireless, ath12k, linux-kernel
On 6/17/2025 4:44 PM, Johan Hovold wrote:
> The read memory barrier added by commit 6b67d2cf14ea ("wifi: ath12k: fix
> ring-buffer corruption") is enough to guarantee ordering also for plain
> descriptor accesses if the length helper is ever inlined so drop the
> unnecessary READ_ONCE().
>
> Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
>
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---
> drivers/net/wireless/ath/ath12k/hal.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c
> index f8bd3837b9dc..726969cfcaec 100644
> --- a/drivers/net/wireless/ath/ath12k/hal.c
> +++ b/drivers/net/wireless/ath/ath12k/hal.c
> @@ -1950,7 +1950,7 @@ u32 ath12k_hal_ce_dst_status_get_length(struct hal_ce_srng_dst_status_desc *desc
> {
> u32 len;
>
> - len = le32_get_bits(READ_ONCE(desc->flags), HAL_CE_DST_STATUS_DESC_FLAGS_LEN);
> + len = le32_get_bits(desc->flags, HAL_CE_DST_STATUS_DESC_FLAGS_LEN);
> desc->flags &= ~cpu_to_le32(HAL_CE_DST_STATUS_DESC_FLAGS_LEN);
>
> return len;
Reviewed-by: Baochen Qiang <quic_bqiang@quicinc.com>
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH v3 3/4] wifi: ath12k: fix source ring-buffer corruption
2025-06-17 8:43 [PATCH v3 0/4] wifi: ath12k: fix dest ring-buffer corruption Johan Hovold
2025-06-17 8:43 ` [PATCH v3 1/4] " Johan Hovold
2025-06-17 8:44 ` [PATCH v3 2/4] wifi: ath12k: use plain access for descriptor length Johan Hovold
@ 2025-06-17 8:44 ` Johan Hovold
2025-06-25 1:54 ` Baochen Qiang
2025-06-17 8:44 ` [PATCH v3 4/4] wifi: ath12k: fix dest ring-buffer corruption when ring is full Johan Hovold
2025-06-26 23:15 ` [PATCH v3 0/4] wifi: ath12k: fix dest ring-buffer corruption Jeff Johnson
4 siblings, 1 reply; 10+ messages in thread
From: Johan Hovold @ 2025-06-17 8:44 UTC (permalink / raw)
To: Jeff Johnson
Cc: Miaoqing Pan, Remi Pommarel, Baochen Qiang, linux-wireless,
ath12k, linux-kernel, Johan Hovold, stable
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: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
Cc: stable@vger.kernel.org # 6.3
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
drivers/net/wireless/ath/ath12k/hal.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c
index 726969cfcaec..d8193d9577bb 100644
--- a/drivers/net/wireless/ath/ath12k/hal.c
+++ b/drivers/net/wireless/ath/ath12k/hal.c
@@ -2178,7 +2178,11 @@ void ath12k_hal_srng_access_end(struct ath12k_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;
@@ -2187,6 +2191,10 @@ void ath12k_hal_srng_access_end(struct ath12k_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.
+ */
ath12k_hif_write32(ab,
(unsigned long)srng->u.src_ring.hp_addr -
(unsigned long)ab->mem,
--
2.49.0
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH v3 3/4] wifi: ath12k: fix source ring-buffer corruption
2025-06-17 8:44 ` [PATCH v3 3/4] wifi: ath12k: fix source ring-buffer corruption Johan Hovold
@ 2025-06-25 1:54 ` Baochen Qiang
0 siblings, 0 replies; 10+ messages in thread
From: Baochen Qiang @ 2025-06-25 1:54 UTC (permalink / raw)
To: Johan Hovold, Jeff Johnson
Cc: Miaoqing Pan, Remi Pommarel, linux-wireless, ath12k, linux-kernel,
stable
On 6/17/2025 4:44 PM, Johan Hovold wrote:
> 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: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
>
> Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
> Cc: stable@vger.kernel.org # 6.3
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---
> drivers/net/wireless/ath/ath12k/hal.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c
> index 726969cfcaec..d8193d9577bb 100644
> --- a/drivers/net/wireless/ath/ath12k/hal.c
> +++ b/drivers/net/wireless/ath/ath12k/hal.c
> @@ -2178,7 +2178,11 @@ void ath12k_hal_srng_access_end(struct ath12k_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;
> @@ -2187,6 +2191,10 @@ void ath12k_hal_srng_access_end(struct ath12k_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.
> + */
> ath12k_hif_write32(ab,
> (unsigned long)srng->u.src_ring.hp_addr -
> (unsigned long)ab->mem,
Reviewed-by: Baochen Qiang <quic_bqiang@quicinc.com>
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH v3 4/4] wifi: ath12k: fix dest ring-buffer corruption when ring is full
2025-06-17 8:43 [PATCH v3 0/4] wifi: ath12k: fix dest ring-buffer corruption Johan Hovold
` (2 preceding siblings ...)
2025-06-17 8:44 ` [PATCH v3 3/4] wifi: ath12k: fix source ring-buffer corruption Johan Hovold
@ 2025-06-17 8:44 ` Johan Hovold
2025-06-25 1:54 ` Baochen Qiang
2025-06-26 23:15 ` [PATCH v3 0/4] wifi: ath12k: fix dest ring-buffer corruption Jeff Johnson
4 siblings, 1 reply; 10+ messages in thread
From: Johan Hovold @ 2025-06-17 8:44 UTC (permalink / raw)
To: Jeff Johnson
Cc: Miaoqing Pan, Remi Pommarel, Baochen Qiang, linux-wireless,
ath12k, linux-kernel, Johan Hovold, stable
Add the missing memory barriers to make sure that destination ring
descriptors are read before updating the tail pointer (and passing
ownership to the device) to avoid memory corruption on weakly ordered
architectures like aarch64 when the ring is full.
Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
Cc: stable@vger.kernel.org # 6.3
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
drivers/net/wireless/ath/ath12k/hal.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c
index d8193d9577bb..6406fcf5d69f 100644
--- a/drivers/net/wireless/ath/ath12k/hal.c
+++ b/drivers/net/wireless/ath/ath12k/hal.c
@@ -2170,7 +2170,6 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng)
{
lockdep_assert_held(&srng->lock);
- /* TODO: See if we need a write memory barrier here */
if (srng->flags & HAL_SRNG_FLAGS_LMAC_RING) {
/* For LMAC rings, ring pointer updates are done through FW and
* hence written to a shared memory location that is read by FW
@@ -2185,7 +2184,11 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng)
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;
+ /* Make sure descriptor is read before updating the
+ * tail pointer.
+ */
+ dma_mb();
+ WRITE_ONCE(*srng->u.dst_ring.tp_addr, srng->u.dst_ring.tp);
}
} else {
if (srng->ring_dir == HAL_SRNG_DIR_SRC) {
@@ -2201,6 +2204,10 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng)
srng->u.src_ring.hp);
} else {
srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr;
+ /* Make sure descriptor is read before updating the
+ * tail pointer.
+ */
+ mb();
ath12k_hif_write32(ab,
(unsigned long)srng->u.dst_ring.tp_addr -
(unsigned long)ab->mem,
--
2.49.0
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH v3 4/4] wifi: ath12k: fix dest ring-buffer corruption when ring is full
2025-06-17 8:44 ` [PATCH v3 4/4] wifi: ath12k: fix dest ring-buffer corruption when ring is full Johan Hovold
@ 2025-06-25 1:54 ` Baochen Qiang
0 siblings, 0 replies; 10+ messages in thread
From: Baochen Qiang @ 2025-06-25 1:54 UTC (permalink / raw)
To: Johan Hovold, Jeff Johnson
Cc: Miaoqing Pan, Remi Pommarel, linux-wireless, ath12k, linux-kernel,
stable
On 6/17/2025 4:44 PM, Johan Hovold wrote:
> Add the missing memory barriers to make sure that destination ring
> descriptors are read before updating the tail pointer (and passing
> ownership to the device) to avoid memory corruption on weakly ordered
> architectures like aarch64 when the ring is full.
>
> Tested-on: WCN7850 hw2.0 WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
>
> Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
> Cc: stable@vger.kernel.org # 6.3
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---
> drivers/net/wireless/ath/ath12k/hal.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/ath12k/hal.c b/drivers/net/wireless/ath/ath12k/hal.c
> index d8193d9577bb..6406fcf5d69f 100644
> --- a/drivers/net/wireless/ath/ath12k/hal.c
> +++ b/drivers/net/wireless/ath/ath12k/hal.c
> @@ -2170,7 +2170,6 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng)
> {
> lockdep_assert_held(&srng->lock);
>
> - /* TODO: See if we need a write memory barrier here */
> if (srng->flags & HAL_SRNG_FLAGS_LMAC_RING) {
> /* For LMAC rings, ring pointer updates are done through FW and
> * hence written to a shared memory location that is read by FW
> @@ -2185,7 +2184,11 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng)
> 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;
> + /* Make sure descriptor is read before updating the
> + * tail pointer.
> + */
> + dma_mb();
> + WRITE_ONCE(*srng->u.dst_ring.tp_addr, srng->u.dst_ring.tp);
> }
> } else {
> if (srng->ring_dir == HAL_SRNG_DIR_SRC) {
> @@ -2201,6 +2204,10 @@ void ath12k_hal_srng_access_end(struct ath12k_base *ab, struct hal_srng *srng)
> srng->u.src_ring.hp);
> } else {
> srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr;
> + /* Make sure descriptor is read before updating the
> + * tail pointer.
> + */
> + mb();
> ath12k_hif_write32(ab,
> (unsigned long)srng->u.dst_ring.tp_addr -
> (unsigned long)ab->mem,
Reviewed-by: Baochen Qiang <quic_bqiang@quicinc.com>
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v3 0/4] wifi: ath12k: fix dest ring-buffer corruption
2025-06-17 8:43 [PATCH v3 0/4] wifi: ath12k: fix dest ring-buffer corruption Johan Hovold
` (3 preceding siblings ...)
2025-06-17 8:44 ` [PATCH v3 4/4] wifi: ath12k: fix dest ring-buffer corruption when ring is full Johan Hovold
@ 2025-06-26 23:15 ` Jeff Johnson
4 siblings, 0 replies; 10+ messages in thread
From: Jeff Johnson @ 2025-06-26 23:15 UTC (permalink / raw)
To: Jeff Johnson, Johan Hovold
Cc: Miaoqing Pan, Remi Pommarel, Baochen Qiang, linux-wireless,
ath12k, linux-kernel
On Tue, 17 Jun 2025 10:43:58 +0200, Johan Hovold wrote:
> As a follow up to commit:
>
> b67d2cf14ea ("wifi: ath12k: fix ring-buffer corruption")
>
> add the remaining missing memory barriers to make sure that destination
> ring descriptors are read after the head pointers to avoid using stale
> data on weakly ordered architectures like aarch64.
>
> [...]
Applied, thanks!
[1/4] wifi: ath12k: fix dest ring-buffer corruption
commit: 8157ce533a60521f21d466eb4de45d9735b19484
[2/4] wifi: ath12k: use plain access for descriptor length
commit: 79390f613d639f7ef913377719cc5094357e53bc
[3/4] wifi: ath12k: fix source ring-buffer corruption
commit: e834da4cbd6fe1d24f89368bf0c80adcad212726
[4/4] wifi: ath12k: fix dest ring-buffer corruption when ring is full
commit: ed32169be1ccb9b1a295275ba7746dc6bf103e80
Best regards,
--
Jeff Johnson <jeff.johnson@oss.qualcomm.com>
^ permalink raw reply [flat|nested] 10+ messages in thread