Re: [PATCH v3] wifi: ath11k: move .max_tx_ring to struct ath11k_hw_hal_params

On 12/28/2025 11:14 PM, Alexandru Gagniuc wrote:
> ".max_tx_ring" is an upper bounds to indexing ".tcl2wbm_rbm_map". It
> is initialized in, core.c, a different file than the array. This
> spaghetti-like relation is fragile and not obvious. Accidentally
> setting ".max_tx_ring" too high leads to a hard to track out-of-
> bounds access and memory corruption.
> 
> There is a small ambiguity on the meaning of "max_tx_ring":
>  - The highest ring, max=3 implies there are 4 rings (0, 1, 2, 3)
>  - The highest number to use for array indexing (there are 3 rings)
> 
> Clarify this dependency by moving ".max_tx_ring" adjacent to the array
> ".tcl2wbm_rbm_map", and name it "num_tx_rings". Use ARRAY_SIZE()
> instead of #defines to initialize the length field.
> 
> The ath11k_hw_hal_params_qca6390 uses fewer num_tx_rings than its map,
> so use a constant to express the correct value. Add a static_assert()
> to fail compilation if the constant is accidentally set too high.
> 
> The intent is to make the code easier to understand rather than fix
> an existing bug.
> 
> Signed-off-by: Alexandru Gagniuc <[email protected]>
> ---
> 
> I am trying to make ath11k work on IPQ9574. My device uses a IPQ9570
> with a QCN5024 as the 2.4 GHz wifi.
> 
> I spent a few days tracking a memory corruption bug caused by
> erroneously setting ".max_tx_ring" too high. I think I would not have
> made this mistake if the initializations of .max_tx_ring and
> .tcl2wbm_rbm_map were right next to each other.
> 
> Changes since v2:
>  - Use ipq5018 rbm_map for ath11k_hw_hal_params_qca6390
>  - Drop unecessarry static_assert
> 
> Changes since v1:
>  - use "num_tx_rings" name instead of "map_len"
>  - make sure debugfs.c is correctly updated
>  - add a static_assert for ath11k_hw_hal_params_qca6390 special case
> ---
>  drivers/net/wireless/ath/ath11k/core.c    | 12 +-----------
>  drivers/net/wireless/ath/ath11k/debugfs.c |  2 +-
>  drivers/net/wireless/ath/ath11k/dp.c      | 12 ++++++------
>  drivers/net/wireless/ath/ath11k/dp.h      |  1 -
>  drivers/net/wireless/ath/ath11k/dp_tx.c   |  9 +++++----
>  drivers/net/wireless/ath/ath11k/hw.c      | 19 ++++++++++++++++++-
>  drivers/net/wireless/ath/ath11k/hw.h      |  3 ++-
>  drivers/net/wireless/ath/ath11k/mac.c     |  2 +-
>  8 files changed, 34 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath11k/core.c b/drivers/net/wireless/ath/ath11k/core.c
> index 812686173ac8a..07199ceecbeb4 100644
> --- a/drivers/net/wireless/ath/ath11k/core.c
> +++ b/drivers/net/wireless/ath/ath11k/core.c
> @@ -100,7 +100,6 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.supports_regdb = false,
>  		.fix_l1ss = true,
>  		.credit_flow = false,
> -		.max_tx_ring = DP_TCL_NUM_RING_MAX,
>  		.hal_params = &ath11k_hw_hal_params_ipq8074,
>  		.supports_dynamic_smps_6ghz = false,
>  		.alloc_cacheable_memory = true,
> @@ -184,7 +183,6 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.supports_regdb = false,
>  		.fix_l1ss = true,
>  		.credit_flow = false,
> -		.max_tx_ring = DP_TCL_NUM_RING_MAX,
>  		.hal_params = &ath11k_hw_hal_params_ipq8074,
>  		.supports_dynamic_smps_6ghz = false,
>  		.alloc_cacheable_memory = true,
> @@ -271,7 +269,6 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.supports_regdb = false,
>  		.fix_l1ss = true,
>  		.credit_flow = true,
> -		.max_tx_ring = DP_TCL_NUM_RING_MAX_QCA6390,
>  		.hal_params = &ath11k_hw_hal_params_qca6390,
>  		.supports_dynamic_smps_6ghz = false,
>  		.alloc_cacheable_memory = false,
> @@ -358,7 +355,6 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.supports_regdb = false,
>  		.fix_l1ss = true,
>  		.credit_flow = false,
> -		.max_tx_ring = DP_TCL_NUM_RING_MAX,
>  		.hal_params = &ath11k_hw_hal_params_ipq8074,
>  		.supports_dynamic_smps_6ghz = true,
>  		.alloc_cacheable_memory = true,
> @@ -445,7 +441,6 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.supports_regdb = true,
>  		.fix_l1ss = false,
>  		.credit_flow = true,
> -		.max_tx_ring = DP_TCL_NUM_RING_MAX_QCA6390,
>  		.hal_params = &ath11k_hw_hal_params_qca6390,
>  		.supports_dynamic_smps_6ghz = false,
>  		.alloc_cacheable_memory = false,
> @@ -533,7 +528,6 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.supports_regdb = true,
>  		.fix_l1ss = false,
>  		.credit_flow = true,
> -		.max_tx_ring = DP_TCL_NUM_RING_MAX_QCA6390,
>  		.hal_params = &ath11k_hw_hal_params_qca6390,
>  		.supports_dynamic_smps_6ghz = false,
>  		.alloc_cacheable_memory = false,
> @@ -619,7 +613,6 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.supports_regdb = true,
>  		.fix_l1ss = false,
>  		.credit_flow = true,
> -		.max_tx_ring = DP_TCL_NUM_RING_MAX,
>  		.hal_params = &ath11k_hw_hal_params_wcn6750,
>  		.supports_dynamic_smps_6ghz = false,
>  		.alloc_cacheable_memory = false,
> @@ -662,7 +655,6 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.qmi_service_ins_id = ATH11K_QMI_WLFW_SERVICE_INS_ID_V01_IPQ8074,
>  		.ring_mask = &ath11k_hw_ring_mask_ipq8074,
>  		.credit_flow = false,
> -		.max_tx_ring = 1,
>  		.spectral = {
>  			.fft_sz = 2,
>  			.fft_pad_sz = 0,
> @@ -698,7 +690,7 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.supports_regdb = false,
>  		.idle_ps = false,
>  		.supports_suspend = false,
> -		.hal_params = &ath11k_hw_hal_params_ipq8074,
> +		.hal_params = &ath11k_hw_hal_params_ipq5018,
>  		.single_pdev_only = false,
>  		.coldboot_cal_mm = true,
>  		.coldboot_cal_ftm = true,
> @@ -789,7 +781,6 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.supports_regdb = true,
>  		.fix_l1ss = false,
>  		.credit_flow = true,
> -		.max_tx_ring = DP_TCL_NUM_RING_MAX_QCA6390,
>  		.hal_params = &ath11k_hw_hal_params_qca6390,
>  		.supports_dynamic_smps_6ghz = false,
>  		.alloc_cacheable_memory = false,
> @@ -876,7 +867,6 @@ static const struct ath11k_hw_params ath11k_hw_params[] = {
>  		.supports_regdb = true,
>  		.fix_l1ss = false,
>  		.credit_flow = true,
> -		.max_tx_ring = DP_TCL_NUM_RING_MAX_QCA6390,
>  		.hal_params = &ath11k_hw_hal_params_qca6390,
>  		.supports_dynamic_smps_6ghz = false,
>  		.alloc_cacheable_memory = false,
> diff --git a/drivers/net/wireless/ath/ath11k/debugfs.c b/drivers/net/wireless/ath/ath11k/debugfs.c
> index 977f945b6e669..50f344803e8fd 100644
> --- a/drivers/net/wireless/ath/ath11k/debugfs.c
> +++ b/drivers/net/wireless/ath/ath11k/debugfs.c
> @@ -707,7 +707,7 @@ static ssize_t ath11k_debugfs_dump_soc_dp_stats(struct file *file,
>  	len += scnprintf(buf + len, size - len, "\nSOC TX STATS:\n");
>  	len += scnprintf(buf + len, size - len, "\nTCL Ring Full Failures:\n");
>  
> -	for (i = 0; i < ab->hw_params.max_tx_ring; i++)
> +	for (i = 0; i < ab->hw_params.hal_params->num_tx_rings; i++)
>  		len += scnprintf(buf + len, size - len, "ring%d: %u\n",
>  				 i, soc_stats->tx_err.desc_na[i]);
>  
> diff --git a/drivers/net/wireless/ath/ath11k/dp.c b/drivers/net/wireless/ath/ath11k/dp.c
> index 56b1a657e0b0f..c940de285276d 100644
> --- a/drivers/net/wireless/ath/ath11k/dp.c
> +++ b/drivers/net/wireless/ath/ath11k/dp.c
> @@ -344,7 +344,7 @@ void ath11k_dp_stop_shadow_timers(struct ath11k_base *ab)
>  	if (!ab->hw_params.supports_shadow_regs)
>  		return;
>  
> -	for (i = 0; i < ab->hw_params.max_tx_ring; i++)
> +	for (i = 0; i < ab->hw_params.hal_params->num_tx_rings; i++)
>  		ath11k_dp_shadow_stop_timer(ab, &ab->dp.tx_ring_timer[i]);
>  
>  	ath11k_dp_shadow_stop_timer(ab, &ab->dp.reo_cmd_timer);
> @@ -359,7 +359,7 @@ static void ath11k_dp_srng_common_cleanup(struct ath11k_base *ab)
>  	ath11k_dp_srng_cleanup(ab, &dp->wbm_desc_rel_ring);
>  	ath11k_dp_srng_cleanup(ab, &dp->tcl_cmd_ring);
>  	ath11k_dp_srng_cleanup(ab, &dp->tcl_status_ring);
> -	for (i = 0; i < ab->hw_params.max_tx_ring; i++) {
> +	for (i = 0; i < ab->hw_params.hal_params->num_tx_rings; i++) {
>  		ath11k_dp_srng_cleanup(ab, &dp->tx_ring[i].tcl_data_ring);
>  		ath11k_dp_srng_cleanup(ab, &dp->tx_ring[i].tcl_comp_ring);
>  	}
> @@ -400,7 +400,7 @@ static int ath11k_dp_srng_common_setup(struct ath11k_base *ab)
>  		goto err;
>  	}
>  
> -	for (i = 0; i < ab->hw_params.max_tx_ring; i++) {
> +	for (i = 0; i < ab->hw_params.hal_params->num_tx_rings; i++) {
>  		tcl_num = ab->hw_params.hal_params->tcl2wbm_rbm_map[i].tcl_ring_num;
>  		wbm_num = ab->hw_params.hal_params->tcl2wbm_rbm_map[i].wbm_ring_num;
>  
> @@ -782,7 +782,7 @@ int ath11k_dp_service_srng(struct ath11k_base *ab,
>  	int i, j;
>  	int tot_work_done = 0;
>  
> -	for (i = 0; i < ab->hw_params.max_tx_ring; i++) {
> +	for (i = 0; i < ab->hw_params.hal_params->num_tx_rings; i++) {
>  		if (BIT(ab->hw_params.hal_params->tcl2wbm_rbm_map[i].wbm_ring_num) &
>  		    ab->hw_params.ring_mask->tx[grp_id])
>  			ath11k_dp_tx_completion_handler(ab, i);
> @@ -1035,7 +1035,7 @@ void ath11k_dp_free(struct ath11k_base *ab)
>  
>  	ath11k_dp_reo_cmd_list_cleanup(ab);
>  
> -	for (i = 0; i < ab->hw_params.max_tx_ring; i++) {
> +	for (i = 0; i < ab->hw_params.hal_params->num_tx_rings; i++) {
>  		spin_lock_bh(&dp->tx_ring[i].tx_idr_lock);
>  		idr_for_each(&dp->tx_ring[i].txbuf_idr,
>  			     ath11k_dp_tx_pending_cleanup, ab);
> @@ -1086,7 +1086,7 @@ int ath11k_dp_alloc(struct ath11k_base *ab)
>  
>  	size = sizeof(struct hal_wbm_release_ring) * DP_TX_COMP_RING_SIZE;
>  
> -	for (i = 0; i < ab->hw_params.max_tx_ring; i++) {
> +	for (i = 0; i < ab->hw_params.hal_params->num_tx_rings; i++) {
>  		idr_init(&dp->tx_ring[i].txbuf_idr);
>  		spin_lock_init(&dp->tx_ring[i].tx_idr_lock);
>  		dp->tx_ring[i].tcl_data_ring_id = i;
> diff --git a/drivers/net/wireless/ath/ath11k/dp.h b/drivers/net/wireless/ath/ath11k/dp.h
> index 7a55afd33be82..1bd513f68a3c3 100644
> --- a/drivers/net/wireless/ath/ath11k/dp.h
> +++ b/drivers/net/wireless/ath/ath11k/dp.h
> @@ -199,7 +199,6 @@ struct ath11k_pdev_dp {
>  #define DP_BA_WIN_SZ_MAX	256
>  
>  #define DP_TCL_NUM_RING_MAX	3
> -#define DP_TCL_NUM_RING_MAX_QCA6390	1
>  
>  #define DP_IDLE_SCATTER_BUFS_MAX 16
>  
> diff --git a/drivers/net/wireless/ath/ath11k/dp_tx.c b/drivers/net/wireless/ath/ath11k/dp_tx.c
> index 562aba66582f3..86e1e6c27b36c 100644
> --- a/drivers/net/wireless/ath/ath11k/dp_tx.c
> +++ b/drivers/net/wireless/ath/ath11k/dp_tx.c
> @@ -91,6 +91,7 @@ int ath11k_dp_tx(struct ath11k *ar, struct ath11k_vif *arvif,
>  	struct hal_srng *tcl_ring;
>  	struct ieee80211_hdr *hdr = (void *)skb->data;
>  	struct dp_tx_ring *tx_ring;
> +	size_t num_tx_rings = ab->hw_params.hal_params->num_tx_rings;
>  	void *hal_tcl_desc;
>  	u8 pool_id;
>  	u8 hal_ring_id;
> @@ -113,7 +114,7 @@ int ath11k_dp_tx(struct ath11k *ar, struct ath11k_vif *arvif,
>  tcl_ring_sel:
>  	tcl_ring_retry = false;
>  
> -	ti.ring_id = ring_selector % ab->hw_params.max_tx_ring;
> +	ti.ring_id = ring_selector % num_tx_rings;
>  	ti.rbm_id = ab->hw_params.hal_params->tcl2wbm_rbm_map[ti.ring_id].rbm_id;
>  
>  	ring_map |= BIT(ti.ring_id);
> @@ -126,7 +127,7 @@ int ath11k_dp_tx(struct ath11k *ar, struct ath11k_vif *arvif,
>  	spin_unlock_bh(&tx_ring->tx_idr_lock);
>  
>  	if (unlikely(ret < 0)) {
> -		if (ring_map == (BIT(ab->hw_params.max_tx_ring) - 1) ||
> +		if (ring_map == (BIT(num_tx_rings) - 1) ||
>  		    !ab->hw_params.tcl_ring_retry) {
>  			atomic_inc(&ab->soc_stats.tx_err.misc_fail);
>  			return -ENOSPC;
> @@ -244,8 +245,8 @@ int ath11k_dp_tx(struct ath11k *ar, struct ath11k_vif *arvif,
>  		 * checking this ring earlier for each pkt tx.
>  		 * Restart ring selection if some rings are not checked yet.
>  		 */
> -		if (unlikely(ring_map != (BIT(ab->hw_params.max_tx_ring)) - 1) &&
> -		    ab->hw_params.tcl_ring_retry && ab->hw_params.max_tx_ring > 1) {
> +		if (unlikely(ring_map != (BIT(num_tx_rings)) - 1) &&
> +		    ab->hw_params.tcl_ring_retry && num_tx_rings > 1) {
>  			tcl_ring_retry = true;
>  			ring_selector++;
>  		}
> diff --git a/drivers/net/wireless/ath/ath11k/hw.c b/drivers/net/wireless/ath/ath11k/hw.c
> index caa6dc12a790b..d19c4b372a2aa 100644
> --- a/drivers/net/wireless/ath/ath11k/hw.c
> +++ b/drivers/net/wireless/ath/ath11k/hw.c
> @@ -2707,6 +2707,14 @@ const struct ath11k_hw_regs wcn6750_regs = {
>  	.hal_reo1_misc_ctl = 0x000005d8,
>  };
>  
> +static const struct ath11k_hw_tcl2wbm_rbm_map ath11k_hw_tcl2wbm_rbm_map_ipq5018[] = {
> +	{
> +		.tcl_ring_num = 0,
> +		.wbm_ring_num = 0,
> +		.rbm_id = HAL_RX_BUF_RBM_SW0_BM,
> +	},
> +};
> +
>  static const struct ath11k_hw_tcl2wbm_rbm_map ath11k_hw_tcl2wbm_rbm_map_ipq8074[] = {
>  	{
>  		.tcl_ring_num = 0,
> @@ -2822,19 +2830,28 @@ const struct ath11k_hw_regs ipq5018_regs = {
>  	.hal_wbm1_release_ring_base_lsb = 0x0000097c,
>  };
>  
> +const struct ath11k_hw_hal_params ath11k_hw_hal_params_ipq5018 = {
> +	.rx_buf_rbm = HAL_RX_BUF_RBM_SW3_BM,
> +	.tcl2wbm_rbm_map = ath11k_hw_tcl2wbm_rbm_map_ipq5018,
> +	.num_tx_rings = ARRAY_SIZE(ath11k_hw_tcl2wbm_rbm_map_ipq5018),
> +};
> +
>  const struct ath11k_hw_hal_params ath11k_hw_hal_params_ipq8074 = {
>  	.rx_buf_rbm = HAL_RX_BUF_RBM_SW3_BM,
>  	.tcl2wbm_rbm_map = ath11k_hw_tcl2wbm_rbm_map_ipq8074,
> +	.num_tx_rings = ARRAY_SIZE(ath11k_hw_tcl2wbm_rbm_map_ipq8074),
>  };
>  
>  const struct ath11k_hw_hal_params ath11k_hw_hal_params_qca6390 = {
>  	.rx_buf_rbm = HAL_RX_BUF_RBM_SW1_BM,
> -	.tcl2wbm_rbm_map = ath11k_hw_tcl2wbm_rbm_map_ipq8074,
> +	.tcl2wbm_rbm_map = ath11k_hw_tcl2wbm_rbm_map_ipq5018,
> +	.num_tx_rings = ARRAY_SIZE(ath11k_hw_tcl2wbm_rbm_map_ipq5018),
>  };
>  
>  const struct ath11k_hw_hal_params ath11k_hw_hal_params_wcn6750 = {
>  	.rx_buf_rbm = HAL_RX_BUF_RBM_SW1_BM,
>  	.tcl2wbm_rbm_map = ath11k_hw_tcl2wbm_rbm_map_wcn6750,
> +	.num_tx_rings = ARRAY_SIZE(ath11k_hw_tcl2wbm_rbm_map_wcn6750),
>  };
>  
>  static const struct cfg80211_sar_freq_ranges ath11k_hw_sar_freq_ranges_wcn6855[] = {
> diff --git a/drivers/net/wireless/ath/ath11k/hw.h b/drivers/net/wireless/ath/ath11k/hw.h
> index 52d9f4c13b136..9db984ac4321c 100644
> --- a/drivers/net/wireless/ath/ath11k/hw.h
> +++ b/drivers/net/wireless/ath/ath11k/hw.h
> @@ -134,6 +134,7 @@ struct ath11k_hw_tcl2wbm_rbm_map {
>  struct ath11k_hw_hal_params {
>  	enum hal_rx_buf_return_buf_manager rx_buf_rbm;
>  	const struct ath11k_hw_tcl2wbm_rbm_map *tcl2wbm_rbm_map;
> +	size_t num_tx_rings;
>  };
>  
>  struct ath11k_hw_params {
> @@ -198,7 +199,6 @@ struct ath11k_hw_params {
>  	bool supports_regdb;
>  	bool fix_l1ss;
>  	bool credit_flow;
> -	u8 max_tx_ring;
>  	const struct ath11k_hw_hal_params *hal_params;
>  	bool supports_dynamic_smps_6ghz;
>  	bool alloc_cacheable_memory;
> @@ -291,6 +291,7 @@ extern const struct ce_ie_addr ath11k_ce_ie_addr_ipq5018;
>  
>  extern const struct ce_remap ath11k_ce_remap_ipq5018;
>  
> +extern const struct ath11k_hw_hal_params ath11k_hw_hal_params_ipq5018;
>  extern const struct ath11k_hw_hal_params ath11k_hw_hal_params_ipq8074;
>  extern const struct ath11k_hw_hal_params ath11k_hw_hal_params_qca6390;
>  extern const struct ath11k_hw_hal_params ath11k_hw_hal_params_wcn6750;
> diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
> index 3276fe443502f..33ebe03380114 100644
> --- a/drivers/net/wireless/ath/ath11k/mac.c
> +++ b/drivers/net/wireless/ath/ath11k/mac.c
> @@ -7392,7 +7392,7 @@ static void ath11k_mac_op_remove_interface(struct ieee80211_hw *hw,
>  	idr_for_each(&ar->txmgmt_idr,
>  		     ath11k_mac_vif_txmgmt_idr_remove, vif);
>  
> -	for (i = 0; i < ab->hw_params.max_tx_ring; i++) {
> +	for (i = 0; i < ab->hw_params.hal_params->num_tx_rings; i++) {
>  		spin_lock_bh(&ab->dp.tx_ring[i].tx_idr_lock);
>  		idr_for_each(&ab->dp.tx_ring[i].txbuf_idr,
>  			     ath11k_mac_vif_unref, vif);

Reviewed-by: Baochen Qiang <[email protected]>