[PATCH ath-next] wifi: ath12k: provide MAC address list for single-radio wiphys

[PATCH ath-next] wifi: ath12k: provide MAC address list for single-radio wiphys

[Vitor Soares]

From: Vitor Soares <vitor.soares@toradex.com>

ath12k supports creating vdevs with addresses provided by mac80211.
Userspace can already make concurrent interfaces work by explicitly
assigning different locally administered addresses.

However, ath12k does not advertise an address list, so when a second
interface is created without an explicit address, mac80211 has nothing
to pick from and falls back to the permanent address. If the first
interface is already running with that address, bringing up the second
one fails with -ENOTUNIQ.

As in ath11k, provide a list of usable addresses so
ieee80211_assign_perm_addr() can hand each new interface an unused one.
Keep the first entry as the radio's own MAC address. Generate the
remaining entries as locally administered variants by changing only the
upper nibble of the first octet, which naturally limits the pool to 16
unique addresses.

Handle only single-radio wiphys. Wiphys with more than one radio behave
exactly as before.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c7-00108-QCAHMTSWPL_V1.0_V2.0_SILICONZ_UPSTREAM-3

Signed-off-by: Vitor Soares <vitor.soares@toradex.com>
---
Note that a device which is not MLO capable registers one wiphy per
radio, so each radio of a multi-radio device also gets a pool, seeded
from that radio's own MAC. I only have single-radio WCN7850 hardware,
so that case is untested.
---
 drivers/net/wireless/ath/ath12k/mac.c | 48 +++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
index 9a775602775d..bee6701f1029 100644
--- a/drivers/net/wireless/ath/ath12k/mac.c
+++ b/drivers/net/wireless/ath/ath12k/mac.c
@@ -14685,6 +14685,50 @@ static void ath12k_mac_cleanup_unregister(struct ath12k *ar)
 	kfree(ar->mac.sbands[NL80211_BAND_6GHZ].channels);
 }
 
+static void ath12k_mac_cleanup_mac_address_list(struct ath12k_hw *ah)
+{
+	kfree(ah->hw->wiphy->addresses);
+}
+
+static void ath12k_mac_setup_mac_address_list(struct ath12k_hw *ah,
+					      const u8 *mac_addr)
+{
+	struct ath12k *ar = ath12k_ah_to_ar(ah, 0);
+	struct mac_address *addresses;
+	u16 n_addresses;
+	int i;
+
+	/* The pool is derived from one base address, so it can describe only a
+	 * single-radio wiphy: with more radios each radio has its own base
+	 * address, possibly from a different ath12k_base.
+	 */
+	if (ah->num_radio != 1)
+		return;
+
+	/* Only the upper nibble of the first octet is varied, so at most 16
+	 * addresses can be derived from one base.
+	 */
+	n_addresses = min_t(u16, TARGET_NUM_VDEVS(ar->ab), 16);
+	if (n_addresses <= 1)
+		return;
+
+	addresses = kzalloc_objs(*addresses, n_addresses);
+	if (!addresses)
+		return;
+
+	ether_addr_copy(addresses[0].addr, mac_addr);
+	for (i = 1; i < n_addresses; i++) {
+		ether_addr_copy(addresses[i].addr, mac_addr);
+		/* set Local Administered Address bit */
+		addresses[i].addr[0] |= 0x2;
+
+		addresses[i].addr[0] += i << 4;
+	}
+
+	ah->hw->wiphy->addresses = addresses;
+	ah->hw->wiphy->n_addresses = n_addresses;
+}
+
 static void ath12k_mac_hw_unregister(struct ath12k_hw *ah)
 {
 	struct ieee80211_hw *hw = ah->hw;
@@ -14704,6 +14748,7 @@ static void ath12k_mac_hw_unregister(struct ath12k_hw *ah)
 		ath12k_mac_cleanup_unregister(ar);
 
 	ath12k_mac_cleanup_iface_combinations(ah);
+	ath12k_mac_cleanup_mac_address_list(ah);
 
 	SET_IEEE80211_DEV(hw, NULL);
 }
@@ -14820,6 +14865,7 @@ static int ath12k_mac_hw_register(struct ath12k_hw *ah)
 	wiphy->available_antennas_tx = antennas_tx;
 
 	SET_IEEE80211_PERM_ADDR(hw, mac_addr);
+	ath12k_mac_setup_mac_address_list(ah, mac_addr);
 	SET_IEEE80211_DEV(hw, ab->dev);
 
 	ret = ath12k_mac_setup_iface_combinations(ah);
@@ -15041,6 +15087,8 @@ static int ath12k_mac_hw_register(struct ath12k_hw *ah)
 		ath12k_mac_cleanup_unregister(ar);
 	}
 
+	ath12k_mac_cleanup_mac_address_list(ah);
+
 	SET_IEEE80211_DEV(hw, NULL);
 
 	return ret;
-- 
2.55.0

Re: [PATCH ath-next] wifi: ath12k: provide MAC address list for single-radio wiphys

[Baochen Qiang]

On 9/2/2026 4:22 PM, Vitor Soares wrote:
> From: Vitor Soares <vitor.soares@toradex.com>
> 
> ath12k supports creating vdevs with addresses provided by mac80211.
> Userspace can already make concurrent interfaces work by explicitly
> assigning different locally administered addresses.
> 
> However, ath12k does not advertise an address list, so when a second
> interface is created without an explicit address, mac80211 has nothing
> to pick from and falls back to the permanent address. If the first
> interface is already running with that address, bringing up the second
> one fails with -ENOTUNIQ.
> 
> As in ath11k, provide a list of usable addresses so
> ieee80211_assign_perm_addr() can hand each new interface an unused one.
> Keep the first entry as the radio's own MAC address. Generate the
> remaining entries as locally administered variants by changing only the
> upper nibble of the first octet, which naturally limits the pool to 16
> unique addresses.
> 

We (Qualcomm) ever internally proposed a similar solution, but it turns out to break chips
like QCN9274 etc. I have forwarded this patch to internal developers, will come back once
get a conclusion.

> Handle only single-radio wiphys. Wiphys with more than one radio behave
> exactly as before.
> 
> Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c7-00108-QCAHMTSWPL_V1.0_V2.0_SILICONZ_UPSTREAM-3
> 
> Signed-off-by: Vitor Soares <vitor.soares@toradex.com>
> ---
> Note that a device which is not MLO capable registers one wiphy per
> radio, so each radio of a multi-radio device also gets a pool, seeded
> from that radio's own MAC. I only have single-radio WCN7850 hardware,
> so that case is untested.
> ---
>  drivers/net/wireless/ath/ath12k/mac.c | 48 +++++++++++++++++++++++++++
>  1 file changed, 48 insertions(+)
> 
> diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
> index 9a775602775d..bee6701f1029 100644
> --- a/drivers/net/wireless/ath/ath12k/mac.c
> +++ b/drivers/net/wireless/ath/ath12k/mac.c
> @@ -14685,6 +14685,50 @@ static void ath12k_mac_cleanup_unregister(struct ath12k *ar)
>  	kfree(ar->mac.sbands[NL80211_BAND_6GHZ].channels);
>  }
>  
> +static void ath12k_mac_cleanup_mac_address_list(struct ath12k_hw *ah)
> +{
> +	kfree(ah->hw->wiphy->addresses);
> +}
> +
> +static void ath12k_mac_setup_mac_address_list(struct ath12k_hw *ah,
> +					      const u8 *mac_addr)
> +{
> +	struct ath12k *ar = ath12k_ah_to_ar(ah, 0);
> +	struct mac_address *addresses;
> +	u16 n_addresses;
> +	int i;
> +
> +	/* The pool is derived from one base address, so it can describe only a
> +	 * single-radio wiphy: with more radios each radio has its own base
> +	 * address, possibly from a different ath12k_base.
> +	 */
> +	if (ah->num_radio != 1)
> +		return;
> +
> +	/* Only the upper nibble of the first octet is varied, so at most 16
> +	 * addresses can be derived from one base.
> +	 */
> +	n_addresses = min_t(u16, TARGET_NUM_VDEVS(ar->ab), 16);
> +	if (n_addresses <= 1)
> +		return;
> +
> +	addresses = kzalloc_objs(*addresses, n_addresses);
> +	if (!addresses)
> +		return;
> +
> +	ether_addr_copy(addresses[0].addr, mac_addr);
> +	for (i = 1; i < n_addresses; i++) {
> +		ether_addr_copy(addresses[i].addr, mac_addr);
> +		/* set Local Administered Address bit */
> +		addresses[i].addr[0] |= 0x2;
> +
> +		addresses[i].addr[0] += i << 4;
> +	}
> +
> +	ah->hw->wiphy->addresses = addresses;
> +	ah->hw->wiphy->n_addresses = n_addresses;
> +}
> +
>  static void ath12k_mac_hw_unregister(struct ath12k_hw *ah)
>  {
>  	struct ieee80211_hw *hw = ah->hw;
> @@ -14704,6 +14748,7 @@ static void ath12k_mac_hw_unregister(struct ath12k_hw *ah)
>  		ath12k_mac_cleanup_unregister(ar);
>  
>  	ath12k_mac_cleanup_iface_combinations(ah);
> +	ath12k_mac_cleanup_mac_address_list(ah);
>  
>  	SET_IEEE80211_DEV(hw, NULL);
>  }
> @@ -14820,6 +14865,7 @@ static int ath12k_mac_hw_register(struct ath12k_hw *ah)
>  	wiphy->available_antennas_tx = antennas_tx;
>  
>  	SET_IEEE80211_PERM_ADDR(hw, mac_addr);
> +	ath12k_mac_setup_mac_address_list(ah, mac_addr);
>  	SET_IEEE80211_DEV(hw, ab->dev);
>  
>  	ret = ath12k_mac_setup_iface_combinations(ah);
> @@ -15041,6 +15087,8 @@ static int ath12k_mac_hw_register(struct ath12k_hw *ah)
>  		ath12k_mac_cleanup_unregister(ar);
>  	}
>  
> +	ath12k_mac_cleanup_mac_address_list(ah);
> +
>  	SET_IEEE80211_DEV(hw, NULL);
>  
>  	return ret;

Re: [PATCH ath-next] wifi: ath12k: provide MAC address list for single-radio wiphys

[Kang Yang]

On 9/2/2026 4:22 PM, Vitor Soares wrote:
> From: Vitor Soares <vitor.soares@toradex.com>
> 
> ath12k supports creating vdevs with addresses provided by mac80211.
> Userspace can already make concurrent interfaces work by explicitly
> assigning different locally administered addresses.
> 
> However, ath12k does not advertise an address list, so when a second
> interface is created without an explicit address, mac80211 has nothing
> to pick from and falls back to the permanent address. If the first
> interface is already running with that address, bringing up the second
> one fails with -ENOTUNIQ.
> 
> As in ath11k, provide a list of usable addresses so
> ieee80211_assign_perm_addr() can hand each new interface an unused one.
> Keep the first entry as the radio's own MAC address. Generate the
> remaining entries as locally administered variants by changing only the
> upper nibble of the first octet, which naturally limits the pool to 16
> unique addresses.
> 
> Handle only single-radio wiphys. Wiphys with more than one radio behave
> exactly as before.
> 
> Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c7-00108-QCAHMTSWPL_V1.0_V2.0_SILICONZ_UPSTREAM-3
> 
> Signed-off-by: Vitor Soares <vitor.soares@toradex.com>
> ---
> Note that a device which is not MLO capable registers one wiphy per
> radio, so each radio of a multi-radio device also gets a pool, seeded
> from that radio's own MAC. I only have single-radio WCN7850 hardware,
> so that case is untested.



Thanks for the patch.

We discussed this internally and found that some Qualcomm platforms use 
wiphy->addresses as an interface MAC pool, while others use it to 
advertise firmware-provided per-radio MAC addresses.

Because of that, using 'ah->num_radio' alone may not be sufficient. Our 
suggestion would be to gate this behavior with a hardware capability 
(inside ath12k_wifi7_hw_params) so that the wiphy->addresses semantics 
remain consistent for a given hardware family.

This would allow platforms that need an interface MAC pool to use the 
proposed address generation logic, while preserving the existing 
per-radio MAC advertisement model on other platforms.



> ---
>   drivers/net/wireless/ath/ath12k/mac.c | 48 +++++++++++++++++++++++++++
>   1 file changed, 48 insertions(+)
> 
> diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
> index 9a775602775d..bee6701f1029 100644
> --- a/drivers/net/wireless/ath/ath12k/mac.c
> +++ b/drivers/net/wireless/ath/ath12k/mac.c
> @@ -14685,6 +14685,50 @@ static void ath12k_mac_cleanup_unregister(struct ath12k *ar)
>   	kfree(ar->mac.sbands[NL80211_BAND_6GHZ].channels);
>   }
>   
> +static void ath12k_mac_cleanup_mac_address_list(struct ath12k_hw *ah)
> +{
> +	kfree(ah->hw->wiphy->addresses);
> +}
> +
> +static void ath12k_mac_setup_mac_address_list(struct ath12k_hw *ah,
> +					      const u8 *mac_addr)
> +{
> +	struct ath12k *ar = ath12k_ah_to_ar(ah, 0);
> +	struct mac_address *addresses;
> +	u16 n_addresses;
> +	int i;
> +
> +	/* The pool is derived from one base address, so it can describe only a
> +	 * single-radio wiphy: with more radios each radio has its own base
> +	 * address, possibly from a different ath12k_base.
> +	 */
> +	if (ah->num_radio != 1)
> +		return;
> +
> +	/* Only the upper nibble of the first octet is varied, so at most 16
> +	 * addresses can be derived from one base.
> +	 */
> +	n_addresses = min_t(u16, TARGET_NUM_VDEVS(ar->ab), 16);
> +	if (n_addresses <= 1)
> +		return;
> +
> +	addresses = kzalloc_objs(*addresses, n_addresses);
> +	if (!addresses)
> +		return;
> +
> +	ether_addr_copy(addresses[0].addr, mac_addr);
> +	for (i = 1; i < n_addresses; i++) {
> +		ether_addr_copy(addresses[i].addr, mac_addr);
> +		/* set Local Administered Address bit */
> +		addresses[i].addr[0] |= 0x2;
> +
> +		addresses[i].addr[0] += i << 4;
> +	}
> +
> +	ah->hw->wiphy->addresses = addresses;
> +	ah->hw->wiphy->n_addresses = n_addresses;
> +}
> +
>   static void ath12k_mac_hw_unregister(struct ath12k_hw *ah)
>   {
>   	struct ieee80211_hw *hw = ah->hw;
> @@ -14704,6 +14748,7 @@ static void ath12k_mac_hw_unregister(struct ath12k_hw *ah)
>   		ath12k_mac_cleanup_unregister(ar);
>   
>   	ath12k_mac_cleanup_iface_combinations(ah);
> +	ath12k_mac_cleanup_mac_address_list(ah);
>   
>   	SET_IEEE80211_DEV(hw, NULL);
>   }
> @@ -14820,6 +14865,7 @@ static int ath12k_mac_hw_register(struct ath12k_hw *ah)
>   	wiphy->available_antennas_tx = antennas_tx;
>   
>   	SET_IEEE80211_PERM_ADDR(hw, mac_addr);
> +	ath12k_mac_setup_mac_address_list(ah, mac_addr);
>   	SET_IEEE80211_DEV(hw, ab->dev);
>   
>   	ret = ath12k_mac_setup_iface_combinations(ah);
> @@ -15041,6 +15087,8 @@ static int ath12k_mac_hw_register(struct ath12k_hw *ah)
>   		ath12k_mac_cleanup_unregister(ar);
>   	}
>   
> +	ath12k_mac_cleanup_mac_address_list(ah);
> +
>   	SET_IEEE80211_DEV(hw, NULL);
>   
>   	return ret;