[PATCH wireless-next] wifi: mt76: fix of_get_mac_address error handling

[PATCH wireless-next] wifi: mt76: fix of_get_mac_address error handling

[Rosen Penev]

Check return value instead of is_valid_ether_addr. The latter is handled
by the former.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/net/wireless/mediatek/mt76/eeprom.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
index 93d91264687f..0f6ccf6ed53d 100644
--- a/drivers/net/wireless/mediatek/mt76/eeprom.c
+++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
@@ -93,7 +93,7 @@ mt76_eeprom_override(struct mt76_phy *phy)
 	if (err == -EPROBE_DEFER)
 		return err;
 
-	if (!is_valid_ether_addr(phy->macaddr)) {
+	if (err) {
 		eth_random_addr(phy->macaddr);
 		dev_info(dev->dev,
 			 "Invalid MAC address, using random address %pM\n",
-- 
2.54.0

Re: [PATCH wireless-next] wifi: mt76: fix of_get_mac_address error handling

[Lorenzo Bianconi]

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> Check return value instead of is_valid_ether_addr. The latter is handled
> by the former.
> 
> Signed-off-by: Rosen Penev <rosenp@gmail.com>

Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>

> ---
>  drivers/net/wireless/mediatek/mt76/eeprom.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
> index 93d91264687f..0f6ccf6ed53d 100644
> --- a/drivers/net/wireless/mediatek/mt76/eeprom.c
> +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
> @@ -93,7 +93,7 @@ mt76_eeprom_override(struct mt76_phy *phy)
>  	if (err == -EPROBE_DEFER)
>  		return err;
>  
> -	if (!is_valid_ether_addr(phy->macaddr)) {
> +	if (err) {
>  		eth_random_addr(phy->macaddr);
>  		dev_info(dev->dev,
>  			 "Invalid MAC address, using random address %pM\n",
> -- 
> 2.54.0
> 

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Re: [PATCH wireless-next] wifi: mt76: fix of_get_mac_address error handling

[Klara Modin]

Hi,

On 2026-04-26 22:17:46 -0700, Rosen Penev wrote:
> Check return value instead of is_valid_ether_addr. The latter is handled
> by the former.
> 
> Signed-off-by: Rosen Penev <rosenp@gmail.com>
> ---
>  drivers/net/wireless/mediatek/mt76/eeprom.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
> index 93d91264687f..0f6ccf6ed53d 100644
> --- a/drivers/net/wireless/mediatek/mt76/eeprom.c
> +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
> @@ -93,7 +93,7 @@ mt76_eeprom_override(struct mt76_phy *phy)
>  	if (err == -EPROBE_DEFER)
>  		return err;
>  
> -	if (!is_valid_ether_addr(phy->macaddr)) {
> +	if (err) {
>  		eth_random_addr(phy->macaddr);
>  		dev_info(dev->dev,
>  			 "Invalid MAC address, using random address %pM\n",
> -- 
> 2.54.0
> 

Recently I have started to see randomized MAC-addresses on my x86 laptop
with a MT7922 and the above message printed in the kernel log. I have
CONFIG_OF turned on, but since this is an ACPI system the device is not
described by any device tree and the earlier of_get_mac_address() likely
fails with -ENODEV. Looking at the !CONFIG_OF stub for
of_get_mac_address it always returns -ENODEV, meaning this will always
randomize the mac in that case too.

Reverting this patch fixes the issue and the correct MAC address is
used. I'm not sure if there is any case where of_get_mac_addres() could
fail in a way that results in a valid MAC address but it seems unlikely
to me.

Regards,
Klara Modin

Re: [PATCH wireless-next] wifi: mt76: fix of_get_mac_address error handling

[Rosen Penev]

On Thu, Jun 18, 2026 at 2:47 PM Klara Modin <klarasmodin@gmail.com> wrote:
>
> Hi,
>
> On 2026-04-26 22:17:46 -0700, Rosen Penev wrote:
> > Check return value instead of is_valid_ether_addr. The latter is handled
> > by the former.
> >
> > Signed-off-by: Rosen Penev <rosenp@gmail.com>
> > ---
> >  drivers/net/wireless/mediatek/mt76/eeprom.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
> > index 93d91264687f..0f6ccf6ed53d 100644
> > --- a/drivers/net/wireless/mediatek/mt76/eeprom.c
> > +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
> > @@ -93,7 +93,7 @@ mt76_eeprom_override(struct mt76_phy *phy)
> >       if (err == -EPROBE_DEFER)
> >               return err;
> >
> > -     if (!is_valid_ether_addr(phy->macaddr)) {
> > +     if (err) {
> >               eth_random_addr(phy->macaddr);
> >               dev_info(dev->dev,
> >                        "Invalid MAC address, using random address %pM\n",
> > --
> > 2.54.0
> >
>
> Recently I have started to see randomized MAC-addresses on my x86 laptop
> with a MT7922 and the above message printed in the kernel log. I have
> CONFIG_OF turned on, but since this is an ACPI system the device is not
> described by any device tree and the earlier of_get_mac_address() likely
> fails with -ENODEV. Looking at the !CONFIG_OF stub for
> of_get_mac_address it always returns -ENODEV, meaning this will always
> randomize the mac in that case too.
IIRC, the normal device_get_mac_address supports nvmem now. Does that
fix your use case?
>
> Reverting this patch fixes the issue and the correct MAC address is
> used. I'm not sure if there is any case where of_get_mac_addres() could
> fail in a way that results in a valid MAC address but it seems unlikely
> to me.
>
> Regards,
> Klara Modin

Re: [PATCH wireless-next] wifi: mt76: fix of_get_mac_address error handling

[Klara Modin]

On 2026-06-18 16:01:45 -0700, Rosen Penev wrote:
> On Thu, Jun 18, 2026 at 2:47 PM Klara Modin <klarasmodin@gmail.com> wrote:
> >
> > Hi,
> >
> > On 2026-04-26 22:17:46 -0700, Rosen Penev wrote:
> > > Check return value instead of is_valid_ether_addr. The latter is handled
> > > by the former.
> > >
> > > Signed-off-by: Rosen Penev <rosenp@gmail.com>
> > > ---
> > >  drivers/net/wireless/mediatek/mt76/eeprom.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
> > > index 93d91264687f..0f6ccf6ed53d 100644
> > > --- a/drivers/net/wireless/mediatek/mt76/eeprom.c
> > > +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
> > > @@ -93,7 +93,7 @@ mt76_eeprom_override(struct mt76_phy *phy)
> > >       if (err == -EPROBE_DEFER)
> > >               return err;
> > >
> > > -     if (!is_valid_ether_addr(phy->macaddr)) {
> > > +     if (err) {
> > >               eth_random_addr(phy->macaddr);
> > >               dev_info(dev->dev,
> > >                        "Invalid MAC address, using random address %pM\n",
> > > --
> > > 2.54.0
> > >
> >
> > Recently I have started to see randomized MAC-addresses on my x86 laptop
> > with a MT7922 and the above message printed in the kernel log. I have
> > CONFIG_OF turned on, but since this is an ACPI system the device is not
> > described by any device tree and the earlier of_get_mac_address() likely
> > fails with -ENODEV. Looking at the !CONFIG_OF stub for
> > of_get_mac_address it always returns -ENODEV, meaning this will always
> > randomize the mac in that case too.

> IIRC, the normal device_get_mac_address supports nvmem now. Does that
> fix your use case?

I tried this:

diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
index b99d7452800f..243a8f2c7bda 100644
--- a/drivers/net/wireless/mediatek/mt76/eeprom.c
+++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
@@ -174,10 +174,9 @@ int
 mt76_eeprom_override(struct mt76_phy *phy)
 {
 	struct mt76_dev *dev = phy->dev;
-	struct device_node *np = dev->dev->of_node;
 	int err;
 
-	err = of_get_mac_address(np, phy->macaddr);
+	err = device_get_mac_address(dev->dev, phy->macaddr);
 	if (err == -EPROBE_DEFER)
 		return err;
 

but I still get a random MAC.

> >
> > Reverting this patch fixes the issue and the correct MAC address is
> > used. I'm not sure if there is any case where of_get_mac_addres() could
> > fail in a way that results in a valid MAC address but it seems unlikely
> > to me.
> >
> > Regards,
> > Klara Modin

Re: [PATCH wireless-next] wifi: mt76: fix of_get_mac_address error handling

[Rosen Penev]

On Thu Jun 18, 2026 at 4:51 PM PDT, Klara Modin wrote:
> On 2026-06-18 16:01:45 -0700, Rosen Penev wrote:
>> On Thu, Jun 18, 2026 at 2:47 PM Klara Modin <klarasmodin@gmail.com> wrote:
>> >
>> > Hi,
>> >
>> > On 2026-04-26 22:17:46 -0700, Rosen Penev wrote:
>> > > Check return value instead of is_valid_ether_addr. The latter is handled
>> > > by the former.
>> > >
>> > > Signed-off-by: Rosen Penev <rosenp@gmail.com>
>> > > ---
>> > >  drivers/net/wireless/mediatek/mt76/eeprom.c | 2 +-
>> > >  1 file changed, 1 insertion(+), 1 deletion(-)
>> > >
>> > > diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
>> > > index 93d91264687f..0f6ccf6ed53d 100644
>> > > --- a/drivers/net/wireless/mediatek/mt76/eeprom.c
>> > > +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
>> > > @@ -93,7 +93,7 @@ mt76_eeprom_override(struct mt76_phy *phy)
>> > >       if (err == -EPROBE_DEFER)
>> > >               return err;
>> > >
>> > > -     if (!is_valid_ether_addr(phy->macaddr)) {
>> > > +     if (err) {
>> > >               eth_random_addr(phy->macaddr);
>> > >               dev_info(dev->dev,
>> > >                        "Invalid MAC address, using random address %pM\n",
>> > > --
>> > > 2.54.0
>> > >
>> >
>> > Recently I have started to see randomized MAC-addresses on my x86 laptop
>> > with a MT7922 and the above message printed in the kernel log. I have
>> > CONFIG_OF turned on, but since this is an ACPI system the device is not
>> > described by any device tree and the earlier of_get_mac_address() likely
>> > fails with -ENODEV. Looking at the !CONFIG_OF stub for
>> > of_get_mac_address it always returns -ENODEV, meaning this will always
>> > randomize the mac in that case too.
>
>> IIRC, the normal device_get_mac_address supports nvmem now. Does that
>> fix your use case?
>
> I tried this:
>
> diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
> index b99d7452800f..243a8f2c7bda 100644
> --- a/drivers/net/wireless/mediatek/mt76/eeprom.c
> +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
> @@ -174,10 +174,9 @@ int
>  mt76_eeprom_override(struct mt76_phy *phy)
>  {
>  	struct mt76_dev *dev = phy->dev;
> -	struct device_node *np = dev->dev->of_node;
>  	int err;
>
> -	err = of_get_mac_address(np, phy->macaddr);
> +	err = device_get_mac_address(dev->dev, phy->macaddr);
>  	if (err == -EPROBE_DEFER)
>  		return err;
>
>
> but I still get a random MAC.
Then the original patch should be reverted. Unfortunate that it doesn't
workq
>
>> >
>> > Reverting this patch fixes the issue and the correct MAC address is
>> > used. I'm not sure if there is any case where of_get_mac_addres() could
>> > fail in a way that results in a valid MAC address but it seems unlikely
>> > to me.
>> >
>> > Regards,
>> > Klara Modin