* Re: [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe
2026-03-17 6:16 [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe Anand Moon
@ 2026-03-17 6:51 ` Heiner Kallweit
2026-03-17 7:59 ` Anand Moon
2026-03-17 17:45 ` kernel test robot
2026-03-19 23:53 ` kernel test robot
2 siblings, 1 reply; 8+ messages in thread
From: Heiner Kallweit @ 2026-03-17 6:51 UTC (permalink / raw)
To: Anand Moon, maintainer:8169 10/100/1000 GIGABIT ETHERNET DRIVER,
Andrew Lunn, David S. Miller, Eric Dumazet, Jakub Kicinski,
Paolo Abeni, Manivannan Sadhasivam, Shawn Lin, Hans Zhang,
Niklas Cassel, open list:8169 10/100/1000 GIGABIT ETHERNET DRIVER,
open list
Cc: Robin Murphy, Danilo Krummrich
On 17.03.2026 07:16, Anand Moon wrote:
> The driver currently assumes the PHY is always at address 0. On some
> hardware or buggy BIOS implementations, the PHY may reside at a
> different address on the MDIO bus. Update r8169_mdio_register()
> to scan the bus for the first available PHY instead of hardcoding
> address 0.
No. The PHY always shows up at (virtual) address 0, due to the
MAC register based way of accessing the internal PHY.
Do you have any concrete example of such a "hardware or buggy bios"?
>
> Additionally, switch to dev_err_probe() in the main probe path to
> provide standardized error handling and cleaner log output for
> registration failures.
>
> Link: https://lore.kernel.org/all/87bc37ee-234c-4568-b72e-955c130a6838@arm.com/
> Fixes: ec392abc9593 ("PCI: dw-rockchip: Enable async probe by default")
> Cc: Robin Murphy <robin.murphy@arm.com>
> Cc: Danilo Krummrich <dakr@kernel.org>
> Cc: Niklas Cassel <cassel@kernel.org>
> Signed-off-by: Anand Moon <linux.amoon@gmail.com>
> ---
> drivers/net/ethernet/realtek/r8169_main.c | 34 ++++++++++++++++-------
> 1 file changed, 24 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
> index 791277e750ba..0fd735beff92 100644
> --- a/drivers/net/ethernet/realtek/r8169_main.c
> +++ b/drivers/net/ethernet/realtek/r8169_main.c
> @@ -5427,7 +5427,8 @@ static int r8169_mdio_register(struct rtl8169_private *tp)
> {
> struct pci_dev *pdev = tp->pci_dev;
> struct mii_bus *new_bus;
> - int ret;
> + struct phy_device *phydev;
> + int ret, addr;
>
> /* On some boards with this chip version the BIOS is buggy and misses
> * to reset the PHY page selector. This results in the PHY ID read
> @@ -5462,18 +5463,31 @@ static int r8169_mdio_register(struct rtl8169_private *tp)
> if (ret)
> return ret;
>
> - tp->phydev = mdiobus_get_phy(new_bus, 0);
> - if (!tp->phydev) {
> + /* find the first (lowest address) PHY on the current MAC's MII bus */
> + for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
> + struct phy_device *tmp = mdiobus_get_phy(new_bus, addr);
> +
> + if (tmp) {
> + phydev = tmp;
> + break;
> + }
> + }
> +
> + if (!phydev) {
> + dev_err(&pdev->dev, "no PHY found on bus\n");
> return -ENODEV;
> - } else if (!tp->phydev->drv) {
> - /* Most chip versions fail with the genphy driver.
> - * Therefore ensure that the dedicated PHY driver is loaded.
> - */
This check is needed. It's seems your actual intention is something completely
different from what you state in the commit message. You try to find a workaround
for the issues with request_module() from async contect, caused by the referenced
change to Rockchip PCI.
> + }
> +
> + /* Most chip versions fail with the genphy driver.
> + * Therefore ensure that the dedicated PHY driver is loaded.
> + */
> + if (!phydev->drv) {
> dev_err(&pdev->dev, "no dedicated PHY driver found for PHY ID 0x%08x, maybe realtek.ko needs to be added to initramfs?\n",
> - tp->phydev->phy_id);
> + phydev->phy_id);
> return -EUNATCH;
> }
>
> + tp->phydev = phydev;
> tp->phydev->mac_managed_pm = true;
> if (rtl_supports_eee(tp))
> phy_support_eee(tp->phydev);
> @@ -5790,11 +5804,11 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
>
> rc = r8169_mdio_register(tp);
> if (rc)
> - return rc;
> + return dev_err_probe(&pdev->dev, rc, "mdio register failure\n");
>
> rc = register_netdev(dev);
> if (rc)
> - return rc;
> + return dev_err_probe(&pdev->dev, rc, "register newdev failure\n");
>
> if (IS_ENABLED(CONFIG_R8169_LEDS)) {
> if (rtl_is_8125(tp))
>
> base-commit: 95c541ddfb0815a0ea8477af778bb13bb075079a
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe
2026-03-17 6:51 ` Heiner Kallweit
@ 2026-03-17 7:59 ` Anand Moon
2026-03-17 9:44 ` Heiner Kallweit
0 siblings, 1 reply; 8+ messages in thread
From: Anand Moon @ 2026-03-17 7:59 UTC (permalink / raw)
To: Heiner Kallweit
Cc: maintainer:8169 10/100/1000 GIGABIT ETHERNET DRIVER, Andrew Lunn,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Manivannan Sadhasivam, Shawn Lin, Hans Zhang, Niklas Cassel,
open list:8169 10/100/1000 GIGABIT ETHERNET DRIVER, open list,
Robin Murphy, Danilo Krummrich
Hi Heiner,
Thanks for your review comments.
On Tue, 17 Mar 2026 at 12:21, Heiner Kallweit <hkallweit1@gmail.com> wrote:
>
> On 17.03.2026 07:16, Anand Moon wrote:
> > The driver currently assumes the PHY is always at address 0. On some
> > hardware or buggy BIOS implementations, the PHY may reside at a
> > different address on the MDIO bus. Update r8169_mdio_register()
> > to scan the bus for the first available PHY instead of hardcoding
> > address 0.
>
> No. The PHY always shows up at (virtual) address 0, due to the
> MAC register based way of accessing the internal PHY.
> Do you have any concrete example of such a "hardware or buggy bios"?
>
Sorry about that, I didn't realize. Unfortunately, my testing shows
this still doesn't
fix the problem, but I still perceive. I modeled the change after some
other drivers,
but clearly, that approach isn't working in this case.
> >
> > Additionally, switch to dev_err_probe() in the main probe path to
> > provide standardized error handling and cleaner log output for
> > registration failures.
> >
> > Link: https://lore.kernel.org/all/87bc37ee-234c-4568-b72e-955c130a6838@arm.com/
> > Fixes: ec392abc9593 ("PCI: dw-rockchip: Enable async probe by default")
> > Cc: Robin Murphy <robin.murphy@arm.com>
> > Cc: Danilo Krummrich <dakr@kernel.org>
> > Cc: Niklas Cassel <cassel@kernel.org>
> > Signed-off-by: Anand Moon <linux.amoon@gmail.com>
> > ---
> > drivers/net/ethernet/realtek/r8169_main.c | 34 ++++++++++++++++-------
> > 1 file changed, 24 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
> > index 791277e750ba..0fd735beff92 100644
> > --- a/drivers/net/ethernet/realtek/r8169_main.c
> > +++ b/drivers/net/ethernet/realtek/r8169_main.c
> > @@ -5427,7 +5427,8 @@ static int r8169_mdio_register(struct rtl8169_private *tp)
> > {
> > struct pci_dev *pdev = tp->pci_dev;
> > struct mii_bus *new_bus;
> > - int ret;
> > + struct phy_device *phydev;
> > + int ret, addr;
> >
> > /* On some boards with this chip version the BIOS is buggy and misses
> > * to reset the PHY page selector. This results in the PHY ID read
> > @@ -5462,18 +5463,31 @@ static int r8169_mdio_register(struct rtl8169_private *tp)
> > if (ret)
> > return ret;
> >
> > - tp->phydev = mdiobus_get_phy(new_bus, 0);
> > - if (!tp->phydev) {
> > + /* find the first (lowest address) PHY on the current MAC's MII bus */
> > + for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
> > + struct phy_device *tmp = mdiobus_get_phy(new_bus, addr);
> > +
> > + if (tmp) {
> > + phydev = tmp;
> > + break;
> > + }
> > + }
> > +
> > + if (!phydev) {
> > + dev_err(&pdev->dev, "no PHY found on bus\n");
> > return -ENODEV;
> > - } else if (!tp->phydev->drv) {
> > - /* Most chip versions fail with the genphy driver.
> > - * Therefore ensure that the dedicated PHY driver is loaded.
> > - */
>
> This check is needed. It's seems your actual intention is something completely
> different from what you state in the commit message. You try to find a workaround
> for the issues with request_module() from async contect, caused by the referenced
> change to Rockchip PCI.
That makes sense, sorry for the noise.
What are your thoughts on using dev_err_probe() for these registration failures?
I thought it might clean up the error path.
Thanks
-Anand
>
> > + }
> > +
> > + /* Most chip versions fail with the genphy driver.
> > + * Therefore ensure that the dedicated PHY driver is loaded.
> > + */
> > + if (!phydev->drv) {
> > dev_err(&pdev->dev, "no dedicated PHY driver found for PHY ID 0x%08x, maybe realtek.ko needs to be added to initramfs?\n",
> > - tp->phydev->phy_id);
> > + phydev->phy_id);
> > return -EUNATCH;
> > }
> >
> > + tp->phydev = phydev;
> > tp->phydev->mac_managed_pm = true;
> > if (rtl_supports_eee(tp))
> > phy_support_eee(tp->phydev);
> > @@ -5790,11 +5804,11 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
> >
> > rc = r8169_mdio_register(tp);
> > if (rc)
> > - return rc;
> > + return dev_err_probe(&pdev->dev, rc, "mdio register failure\n");
> >
> > rc = register_netdev(dev);
> > if (rc)
> > - return rc;
> > + return dev_err_probe(&pdev->dev, rc, "register newdev failure\n");
> >
> > if (IS_ENABLED(CONFIG_R8169_LEDS)) {
> > if (rtl_is_8125(tp))
> >
> > base-commit: 95c541ddfb0815a0ea8477af778bb13bb075079a
>
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe
2026-03-17 7:59 ` Anand Moon
@ 2026-03-17 9:44 ` Heiner Kallweit
2026-03-17 14:11 ` Anand Moon
0 siblings, 1 reply; 8+ messages in thread
From: Heiner Kallweit @ 2026-03-17 9:44 UTC (permalink / raw)
To: Anand Moon
Cc: maintainer:8169 10/100/1000 GIGABIT ETHERNET DRIVER, Andrew Lunn,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Manivannan Sadhasivam, Shawn Lin, Hans Zhang, Niklas Cassel,
open list:8169 10/100/1000 GIGABIT ETHERNET DRIVER, open list,
Robin Murphy, Danilo Krummrich
On 17.03.2026 08:59, Anand Moon wrote:
> Hi Heiner,
>
> Thanks for your review comments.
>
> On Tue, 17 Mar 2026 at 12:21, Heiner Kallweit <hkallweit1@gmail.com> wrote:
>>
>> On 17.03.2026 07:16, Anand Moon wrote:
>>> The driver currently assumes the PHY is always at address 0. On some
>>> hardware or buggy BIOS implementations, the PHY may reside at a
>>> different address on the MDIO bus. Update r8169_mdio_register()
>>> to scan the bus for the first available PHY instead of hardcoding
>>> address 0.
>>
>> No. The PHY always shows up at (virtual) address 0, due to the
>> MAC register based way of accessing the internal PHY.
>> Do you have any concrete example of such a "hardware or buggy bios"?
>>
> Sorry about that, I didn't realize. Unfortunately, my testing shows
> this still doesn't
> fix the problem, but I still perceive. I modeled the change after some
> other drivers,
> but clearly, that approach isn't working in this case.
>>>
>>> Additionally, switch to dev_err_probe() in the main probe path to
>>> provide standardized error handling and cleaner log output for
>>> registration failures.
>>>
>>> Link: https://lore.kernel.org/all/87bc37ee-234c-4568-b72e-955c130a6838@arm.com/
>>> Fixes: ec392abc9593 ("PCI: dw-rockchip: Enable async probe by default")
>>> Cc: Robin Murphy <robin.murphy@arm.com>
>>> Cc: Danilo Krummrich <dakr@kernel.org>
>>> Cc: Niklas Cassel <cassel@kernel.org>
>>> Signed-off-by: Anand Moon <linux.amoon@gmail.com>
>>> ---
>>> drivers/net/ethernet/realtek/r8169_main.c | 34 ++++++++++++++++-------
>>> 1 file changed, 24 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
>>> index 791277e750ba..0fd735beff92 100644
>>> --- a/drivers/net/ethernet/realtek/r8169_main.c
>>> +++ b/drivers/net/ethernet/realtek/r8169_main.c
>>> @@ -5427,7 +5427,8 @@ static int r8169_mdio_register(struct rtl8169_private *tp)
>>> {
>>> struct pci_dev *pdev = tp->pci_dev;
>>> struct mii_bus *new_bus;
>>> - int ret;
>>> + struct phy_device *phydev;
>>> + int ret, addr;
>>>
>>> /* On some boards with this chip version the BIOS is buggy and misses
>>> * to reset the PHY page selector. This results in the PHY ID read
>>> @@ -5462,18 +5463,31 @@ static int r8169_mdio_register(struct rtl8169_private *tp)
>>> if (ret)
>>> return ret;
>>>
>>> - tp->phydev = mdiobus_get_phy(new_bus, 0);
>>> - if (!tp->phydev) {
>>> + /* find the first (lowest address) PHY on the current MAC's MII bus */
>>> + for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
>>> + struct phy_device *tmp = mdiobus_get_phy(new_bus, addr);
>>> +
>>> + if (tmp) {
>>> + phydev = tmp;
>>> + break;
>>> + }
>>> + }
>>> +
>>> + if (!phydev) {
>>> + dev_err(&pdev->dev, "no PHY found on bus\n");
>>> return -ENODEV;
>>> - } else if (!tp->phydev->drv) {
>>> - /* Most chip versions fail with the genphy driver.
>>> - * Therefore ensure that the dedicated PHY driver is loaded.
>>> - */
>>
>> This check is needed. It's seems your actual intention is something completely
>> different from what you state in the commit message. You try to find a workaround
>> for the issues with request_module() from async contect, caused by the referenced
>> change to Rockchip PCI.
> That makes sense, sorry for the noise.
>
> What are your thoughts on using dev_err_probe() for these registration failures?
> I thought it might clean up the error path.
>
I'm not aware of any realistic scenario where these calls would fail (w/o printing
an error message before). So adding an error message wouldn't hurt, but it also
wouldn't be beneficial enough to justify a patch.
> Thanks
> -Anand
>>
>>> + }
>>> +
>>> + /* Most chip versions fail with the genphy driver.
>>> + * Therefore ensure that the dedicated PHY driver is loaded.
>>> + */
>>> + if (!phydev->drv) {
>>> dev_err(&pdev->dev, "no dedicated PHY driver found for PHY ID 0x%08x, maybe realtek.ko needs to be added to initramfs?\n",
>>> - tp->phydev->phy_id);
>>> + phydev->phy_id);
>>> return -EUNATCH;
>>> }
>>>
>>> + tp->phydev = phydev;
>>> tp->phydev->mac_managed_pm = true;
>>> if (rtl_supports_eee(tp))
>>> phy_support_eee(tp->phydev);
>>> @@ -5790,11 +5804,11 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
>>>
>>> rc = r8169_mdio_register(tp);
>>> if (rc)
>>> - return rc;
>>> + return dev_err_probe(&pdev->dev, rc, "mdio register failure\n");
>>>
>>> rc = register_netdev(dev);
>>> if (rc)
>>> - return rc;
>>> + return dev_err_probe(&pdev->dev, rc, "register newdev failure\n");
>>>
>>> if (IS_ENABLED(CONFIG_R8169_LEDS)) {
>>> if (rtl_is_8125(tp))
>>>
>>> base-commit: 95c541ddfb0815a0ea8477af778bb13bb075079a
>>
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe
2026-03-17 9:44 ` Heiner Kallweit
@ 2026-03-17 14:11 ` Anand Moon
0 siblings, 0 replies; 8+ messages in thread
From: Anand Moon @ 2026-03-17 14:11 UTC (permalink / raw)
To: Heiner Kallweit
Cc: maintainer:8169 10/100/1000 GIGABIT ETHERNET DRIVER, Andrew Lunn,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Manivannan Sadhasivam, Shawn Lin, Hans Zhang, Niklas Cassel,
open list:8169 10/100/1000 GIGABIT ETHERNET DRIVER, open list,
Robin Murphy, Danilo Krummrich
Hi Heiner,
On Tue, 17 Mar 2026 at 15:14, Heiner Kallweit <hkallweit1@gmail.com> wrote:
>
> On 17.03.2026 08:59, Anand Moon wrote:
> > Hi Heiner,
> >
> > Thanks for your review comments.
> >
> > On Tue, 17 Mar 2026 at 12:21, Heiner Kallweit <hkallweit1@gmail.com> wrote:
> >>
> >> On 17.03.2026 07:16, Anand Moon wrote:
> >>> The driver currently assumes the PHY is always at address 0. On some
> >>> hardware or buggy BIOS implementations, the PHY may reside at a
> >>> different address on the MDIO bus. Update r8169_mdio_register()
> >>> to scan the bus for the first available PHY instead of hardcoding
> >>> address 0.
> >>
> >> No. The PHY always shows up at (virtual) address 0, due to the
> >> MAC register based way of accessing the internal PHY.
> >> Do you have any concrete example of such a "hardware or buggy bios"?
> >>
> > Sorry about that, I didn't realize. Unfortunately, my testing shows
> > this still doesn't
> > fix the problem, but I still perceive. I modeled the change after some
> > other drivers,
> > but clearly, that approach isn't working in this case.
> >>>
> >>
> >> This check is needed. It's seems your actual intention is something completely
> >> different from what you state in the commit message. You try to find a workaround
> >> for the issues with request_module() from async contect, caused by the referenced
> >> change to Rockchip PCI.
> > That makes sense, sorry for the noise.
> >
> > What are your thoughts on using dev_err_probe() for these registration failures?
> > I thought it might clean up the error path.
> >
> I'm not aware of any realistic scenario where these calls would fail (w/o printing
> an error message before). So adding an error message wouldn't hurt, but it also
> wouldn't be beneficial enough to justify a patch.
>
If we enable .probe_type = PROBE_PREFER_ASYNCHRONOUS in pcie-dw-rockchip.c,
The r8169 module probe will fail due to the module’s request for
synchronous probing.
[1] https://lore.kernel.org/all/87bc37ee-234c-4568-b72e-955c130a6838@arm.com/
Some were in the module, but the probe failed to load the module or firmware.
I hope these changes will resolve the probe warning.
----->8-----
diff --git a/drivers/net/ethernet/realtek/r8169_main.c
b/drivers/net/ethernet/realtek/r8169_main.c
index 791277e750ba..8b7858f6dc6d 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -5790,11 +5790,11 @@ static int rtl_init_one(struct pci_dev *pdev,
const struct pci_device_id *ent)
rc = r8169_mdio_register(tp);
if (rc)
- return rc;
+ return dev_err_probe(&pdev->dev, rc, "mdio register failure\n");
rc = register_netdev(dev);
if (rc)
- return rc;
+ return dev_err_probe(&pdev->dev, rc, "register newdev
failure\n");
if (IS_ENABLED(CONFIG_R8169_LEDS)) {
if (rtl_is_8125(tp))
Thanks
-Anand
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe
2026-03-17 6:16 [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe Anand Moon
2026-03-17 6:51 ` Heiner Kallweit
@ 2026-03-17 17:45 ` kernel test robot
2026-03-19 23:53 ` kernel test robot
2 siblings, 0 replies; 8+ messages in thread
From: kernel test robot @ 2026-03-17 17:45 UTC (permalink / raw)
To: Anand Moon, Heiner Kallweit, Andrew Lunn, David S. Miller,
Eric Dumazet, Jakub Kicinski, Paolo Abeni, Manivannan Sadhasivam,
Shawn Lin, Hans Zhang, Niklas Cassel, linux-kernel
Cc: llvm, oe-kbuild-all, netdev, Anand Moon, Robin Murphy,
Danilo Krummrich
Hi Anand,
kernel test robot noticed the following build warnings:
[auto build test WARNING on 95c541ddfb0815a0ea8477af778bb13bb075079a]
url: https://github.com/intel-lab-lkp/linux/commits/Anand-Moon/r8169-Fix-PHY-lookup-for-mdiobus_get_phy-and-improve-error-reporting-during-probe/20260317-183327
base: 95c541ddfb0815a0ea8477af778bb13bb075079a
patch link: https://lore.kernel.org/r/20260317061700.7734-1-linux.amoon%40gmail.com
patch subject: [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe
config: x86_64-kexec (https://download.01.org/0day-ci/archive/20260317/202603171855.OtM7sS7W-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260317/202603171855.OtM7sS7W-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202603171855.OtM7sS7W-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/net/ethernet/realtek/r8169_main.c:5467:17: warning: variable 'phydev' is used uninitialized whenever 'for' loop exits because its condition is false [-Wsometimes-uninitialized]
5467 | for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
| ^~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/realtek/r8169_main.c:5476:7: note: uninitialized use occurs here
5476 | if (!phydev) {
| ^~~~~~
drivers/net/ethernet/realtek/r8169_main.c:5467:17: note: remove the condition if it is always true
5467 | for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
| ^~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/realtek/r8169_main.c:5430:27: note: initialize the variable 'phydev' to silence this warning
5430 | struct phy_device *phydev;
| ^
| = NULL
1 warning generated.
vim +5467 drivers/net/ethernet/realtek/r8169_main.c
5425
5426 static int r8169_mdio_register(struct rtl8169_private *tp)
5427 {
5428 struct pci_dev *pdev = tp->pci_dev;
5429 struct mii_bus *new_bus;
5430 struct phy_device *phydev;
5431 int ret, addr;
5432
5433 /* On some boards with this chip version the BIOS is buggy and misses
5434 * to reset the PHY page selector. This results in the PHY ID read
5435 * accessing registers on a different page, returning a more or
5436 * less random value. Fix this by resetting the page selector first.
5437 */
5438 if (tp->mac_version == RTL_GIGA_MAC_VER_25 ||
5439 tp->mac_version == RTL_GIGA_MAC_VER_26)
5440 r8169_mdio_write(tp, 0x1f, 0);
5441
5442 new_bus = devm_mdiobus_alloc(&pdev->dev);
5443 if (!new_bus)
5444 return -ENOMEM;
5445
5446 new_bus->name = "r8169";
5447 new_bus->priv = tp;
5448 new_bus->parent = &pdev->dev;
5449 new_bus->irq[0] = PHY_MAC_INTERRUPT;
5450 new_bus->phy_mask = GENMASK(31, 1);
5451 snprintf(new_bus->id, MII_BUS_ID_SIZE, "r8169-%x-%x",
5452 pci_domain_nr(pdev->bus), pci_dev_id(pdev));
5453
5454 new_bus->read = r8169_mdio_read_reg;
5455 new_bus->write = r8169_mdio_write_reg;
5456
5457 if (tp->mac_version >= RTL_GIGA_MAC_VER_40) {
5458 new_bus->read_c45 = r8169_mdio_read_reg_c45;
5459 new_bus->write_c45 = r8169_mdio_write_reg_c45;
5460 }
5461
5462 ret = devm_mdiobus_register(&pdev->dev, new_bus);
5463 if (ret)
5464 return ret;
5465
5466 /* find the first (lowest address) PHY on the current MAC's MII bus */
> 5467 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
5468 struct phy_device *tmp = mdiobus_get_phy(new_bus, addr);
5469
5470 if (tmp) {
5471 phydev = tmp;
5472 break;
5473 }
5474 }
5475
5476 if (!phydev) {
5477 dev_err(&pdev->dev, "no PHY found on bus\n");
5478 return -ENODEV;
5479 }
5480
5481 /* Most chip versions fail with the genphy driver.
5482 * Therefore ensure that the dedicated PHY driver is loaded.
5483 */
5484 if (!phydev->drv) {
5485 dev_err(&pdev->dev, "no dedicated PHY driver found for PHY ID 0x%08x, maybe realtek.ko needs to be added to initramfs?\n",
5486 phydev->phy_id);
5487 return -EUNATCH;
5488 }
5489
5490 tp->phydev = phydev;
5491 tp->phydev->mac_managed_pm = true;
5492 if (rtl_supports_eee(tp))
5493 phy_support_eee(tp->phydev);
5494 phy_support_asym_pause(tp->phydev);
5495
5496 /* mimic behavior of r8125/r8126 vendor drivers */
5497 if (tp->mac_version == RTL_GIGA_MAC_VER_61)
5498 phy_disable_eee_mode(tp->phydev,
5499 ETHTOOL_LINK_MODE_2500baseT_Full_BIT);
5500
5501 /* PHY will be woken up in rtl_open() */
5502 phy_suspend(tp->phydev);
5503
5504 return 0;
5505 }
5506
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe
2026-03-17 6:16 [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe Anand Moon
2026-03-17 6:51 ` Heiner Kallweit
2026-03-17 17:45 ` kernel test robot
@ 2026-03-19 23:53 ` kernel test robot
2026-03-20 3:06 ` Anand Moon
2 siblings, 1 reply; 8+ messages in thread
From: kernel test robot @ 2026-03-19 23:53 UTC (permalink / raw)
To: Anand Moon, Heiner Kallweit, Andrew Lunn, David S. Miller,
Eric Dumazet, Jakub Kicinski, Paolo Abeni, Manivannan Sadhasivam,
Shawn Lin, Hans Zhang, Niklas Cassel, linux-kernel
Cc: llvm, oe-kbuild-all, netdev, Anand Moon, Robin Murphy,
Danilo Krummrich
Hi Anand,
kernel test robot noticed the following build warnings:
[auto build test WARNING on 95c541ddfb0815a0ea8477af778bb13bb075079a]
url: https://github.com/intel-lab-lkp/linux/commits/Anand-Moon/r8169-Fix-PHY-lookup-for-mdiobus_get_phy-and-improve-error-reporting-during-probe/20260317-183327
base: 95c541ddfb0815a0ea8477af778bb13bb075079a
patch link: https://lore.kernel.org/r/20260317061700.7734-1-linux.amoon%40gmail.com
patch subject: [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe
config: s390-allmodconfig (https://download.01.org/0day-ci/archive/20260320/202603200758.vueafhDW-lkp@intel.com/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260320/202603200758.vueafhDW-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202603200758.vueafhDW-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/net/ethernet/realtek/r8169_main.c:5467:17: warning: variable 'phydev' is used uninitialized whenever 'for' loop exits because its condition is false [-Wsometimes-uninitialized]
5467 | for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
| ^~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/realtek/r8169_main.c:5476:7: note: uninitialized use occurs here
5476 | if (!phydev) {
| ^~~~~~
drivers/net/ethernet/realtek/r8169_main.c:5467:17: note: remove the condition if it is always true
5467 | for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
| ^~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/realtek/r8169_main.c:5430:27: note: initialize the variable 'phydev' to silence this warning
5430 | struct phy_device *phydev;
| ^
| = NULL
1 warning generated.
vim +5467 drivers/net/ethernet/realtek/r8169_main.c
5425
5426 static int r8169_mdio_register(struct rtl8169_private *tp)
5427 {
5428 struct pci_dev *pdev = tp->pci_dev;
5429 struct mii_bus *new_bus;
5430 struct phy_device *phydev;
5431 int ret, addr;
5432
5433 /* On some boards with this chip version the BIOS is buggy and misses
5434 * to reset the PHY page selector. This results in the PHY ID read
5435 * accessing registers on a different page, returning a more or
5436 * less random value. Fix this by resetting the page selector first.
5437 */
5438 if (tp->mac_version == RTL_GIGA_MAC_VER_25 ||
5439 tp->mac_version == RTL_GIGA_MAC_VER_26)
5440 r8169_mdio_write(tp, 0x1f, 0);
5441
5442 new_bus = devm_mdiobus_alloc(&pdev->dev);
5443 if (!new_bus)
5444 return -ENOMEM;
5445
5446 new_bus->name = "r8169";
5447 new_bus->priv = tp;
5448 new_bus->parent = &pdev->dev;
5449 new_bus->irq[0] = PHY_MAC_INTERRUPT;
5450 new_bus->phy_mask = GENMASK(31, 1);
5451 snprintf(new_bus->id, MII_BUS_ID_SIZE, "r8169-%x-%x",
5452 pci_domain_nr(pdev->bus), pci_dev_id(pdev));
5453
5454 new_bus->read = r8169_mdio_read_reg;
5455 new_bus->write = r8169_mdio_write_reg;
5456
5457 if (tp->mac_version >= RTL_GIGA_MAC_VER_40) {
5458 new_bus->read_c45 = r8169_mdio_read_reg_c45;
5459 new_bus->write_c45 = r8169_mdio_write_reg_c45;
5460 }
5461
5462 ret = devm_mdiobus_register(&pdev->dev, new_bus);
5463 if (ret)
5464 return ret;
5465
5466 /* find the first (lowest address) PHY on the current MAC's MII bus */
> 5467 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
5468 struct phy_device *tmp = mdiobus_get_phy(new_bus, addr);
5469
5470 if (tmp) {
5471 phydev = tmp;
5472 break;
5473 }
5474 }
5475
5476 if (!phydev) {
5477 dev_err(&pdev->dev, "no PHY found on bus\n");
5478 return -ENODEV;
5479 }
5480
5481 /* Most chip versions fail with the genphy driver.
5482 * Therefore ensure that the dedicated PHY driver is loaded.
5483 */
5484 if (!phydev->drv) {
5485 dev_err(&pdev->dev, "no dedicated PHY driver found for PHY ID 0x%08x, maybe realtek.ko needs to be added to initramfs?\n",
5486 phydev->phy_id);
5487 return -EUNATCH;
5488 }
5489
5490 tp->phydev = phydev;
5491 tp->phydev->mac_managed_pm = true;
5492 if (rtl_supports_eee(tp))
5493 phy_support_eee(tp->phydev);
5494 phy_support_asym_pause(tp->phydev);
5495
5496 /* mimic behavior of r8125/r8126 vendor drivers */
5497 if (tp->mac_version == RTL_GIGA_MAC_VER_61)
5498 phy_disable_eee_mode(tp->phydev,
5499 ETHTOOL_LINK_MODE_2500baseT_Full_BIT);
5500
5501 /* PHY will be woken up in rtl_open() */
5502 phy_suspend(tp->phydev);
5503
5504 return 0;
5505 }
5506
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe
2026-03-19 23:53 ` kernel test robot
@ 2026-03-20 3:06 ` Anand Moon
0 siblings, 0 replies; 8+ messages in thread
From: Anand Moon @ 2026-03-20 3:06 UTC (permalink / raw)
To: kernel test robot
Cc: Heiner Kallweit, Andrew Lunn, David S. Miller, Eric Dumazet,
Jakub Kicinski, Paolo Abeni, Manivannan Sadhasivam, Shawn Lin,
Hans Zhang, Niklas Cassel, linux-kernel, llvm, oe-kbuild-all,
netdev, Robin Murphy, Danilo Krummrich
Hi Kernel test robot,
On Fri, 20 Mar 2026 at 05:25, kernel test robot <lkp@intel.com> wrote:
>
> Hi Anand,
>
> kernel test robot noticed the following build warnings:
>
> [auto build test WARNING on 95c541ddfb0815a0ea8477af778bb13bb075079a]
>
> url: https://github.com/intel-lab-lkp/linux/commits/Anand-Moon/r8169-Fix-PHY-lookup-for-mdiobus_get_phy-and-improve-error-reporting-during-probe/20260317-183327
> base: 95c541ddfb0815a0ea8477af778bb13bb075079a
> patch link: https://lore.kernel.org/r/20260317061700.7734-1-linux.amoon%40gmail.com
> patch subject: [PATCH next v1] r8169: Fix PHY lookup for mdiobus_get_phy() and improve error reporting during probe
> config: s390-allmodconfig (https://download.01.org/0day-ci/archive/20260320/202603200758.vueafhDW-lkp@intel.com/config)
> compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260320/202603200758.vueafhDW-lkp@intel.com/reproduce)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202603200758.vueafhDW-lkp@intel.com/
>
> All warnings (new ones prefixed by >>):
Please discard this patch.
Thanks
-Anand
^ permalink raw reply [flat|nested] 8+ messages in thread