next-20250813 s390 allyesconfig undefined reference to `stmmac_simple_pm_ops'

next-20250813 s390 allyesconfig undefined reference to `stmmac_simple_pm_ops'

[Naresh Kamboju]

Build regressions were detected on the s390 architecture with the
Linux next-20250813 tag when building with the allyesconfig configuration.

The failure is caused by unresolved symbol references to stmmac_simple_pm_ops
in multiple STMMAC driver object files, resulting in a link error during
vmlinux generation.

First seen on next-20250813
Good: next-20250812
Bad: next-20250813 and next-20250819

Regression Analysis:
- New regression? yes
- Reproducibility? yes

* s390, build
  - gcc-13-allyesconfig

Boot regression: next-20250813 s390 allyesconfig undefined reference
to `stmmac_simple_pm_ops'

Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>

## Build log
s390x-linux-gnu-ld:
drivers/net/ethernet/stmicro/stmmac/dwmac-rk.o:(.data.rel+0xa0):
undefined reference to `stmmac_simple_pm_ops'
s390x-linux-gnu-ld:
drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.o:(.data.rel+0xa0):
undefined reference to `stmmac_simple_pm_ops'
s390x-linux-gnu-ld:
drivers/net/ethernet/stmicro/stmmac/stmmac_pci.o:(.data.rel+0xe0):
undefined reference to `stmmac_simple_pm_ops'
s390x-linux-gnu-ld:
drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.o:(.data.rel+0xe0):
undefined reference to `stmmac_simple_pm_ops'
make[3]: *** [/scripts/Makefile.vmlinux:91: vmlinux.unstripped] Error 1

## Source
* Kernel version: 6.17.0-rc2
* Git tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next.git
* Git describe: next-20250818
* Git commit: 3ac864c2d9bb8608ee236e89bf561811613abfce
* Architectures: s390
* Toolchains: gcc-13
* Kconfigs: allyesconfig

## Build
* Build log: https://qa-reports.linaro.org/api/testruns/29579401/log_file/
* Build details:
https://regressions.linaro.org/lkft/linux-next-master/next-20250818/build/gcc-13-allyesconfig/
* Build plan: https://tuxapi.tuxsuite.com/v1/groups/linaro/projects/lkft/builds/31RcVYdjsdhroYxXs4TJYixUCaE
* Build link: https://storage.tuxsuite.com/public/linaro/lkft/builds/31RcVYdjsdhroYxXs4TJYixUCaE/
* Kernel config:
https://storage.tuxsuite.com/public/linaro/lkft/builds/31RcVYdjsdhroYxXs4TJYixUCaE/config

--
Linaro LKFT
https://lkft.linaro.org

Re: next-20250813 s390 allyesconfig undefined reference to `stmmac_simple_pm_ops'

[Alexander Gordeev]

On Tue, Aug 19, 2025 at 03:07:56PM +0530, Naresh Kamboju wrote:

Hi Naresh,

> Build regressions were detected on the s390 architecture with the
> Linux next-20250813 tag when building with the allyesconfig configuration.
> 
> The failure is caused by unresolved symbol references to stmmac_simple_pm_ops
> in multiple STMMAC driver object files, resulting in a link error during
> vmlinux generation.
> 
> First seen on next-20250813
> Good: next-20250812
> Bad: next-20250813 and next-20250819
> 
> Regression Analysis:
> - New regression? yes
> - Reproducibility? yes
> 
> * s390, build
>   - gcc-13-allyesconfig
> 
> Boot regression: next-20250813 s390 allyesconfig undefined reference
> to `stmmac_simple_pm_ops'
> 
> Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
> 
> ## Build log
> s390x-linux-gnu-ld:
> drivers/net/ethernet/stmicro/stmmac/dwmac-rk.o:(.data.rel+0xa0):
> undefined reference to `stmmac_simple_pm_ops'
> s390x-linux-gnu-ld:
> drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.o:(.data.rel+0xa0):
> undefined reference to `stmmac_simple_pm_ops'
> s390x-linux-gnu-ld:
> drivers/net/ethernet/stmicro/stmmac/stmmac_pci.o:(.data.rel+0xe0):
> undefined reference to `stmmac_simple_pm_ops'
> s390x-linux-gnu-ld:
> drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.o:(.data.rel+0xe0):
> undefined reference to `stmmac_simple_pm_ops'
> make[3]: *** [/scripts/Makefile.vmlinux:91: vmlinux.unstripped] Error 1
> 
> ## Source
> * Kernel version: 6.17.0-rc2
> * Git tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next.git
> * Git describe: next-20250818
> * Git commit: 3ac864c2d9bb8608ee236e89bf561811613abfce
> * Architectures: s390
> * Toolchains: gcc-13
> * Kconfigs: allyesconfig
> 
> ## Build
> * Build log: https://qa-reports.linaro.org/api/testruns/29579401/log_file/
> * Build details:
> https://regressions.linaro.org/lkft/linux-next-master/next-20250818/build/gcc-13-allyesconfig/
> * Build plan: https://tuxapi.tuxsuite.com/v1/groups/linaro/projects/lkft/builds/31RcVYdjsdhroYxXs4TJYixUCaE
> * Build link: https://storage.tuxsuite.com/public/linaro/lkft/builds/31RcVYdjsdhroYxXs4TJYixUCaE/
> * Kernel config:
> https://storage.tuxsuite.com/public/linaro/lkft/builds/31RcVYdjsdhroYxXs4TJYixUCaE/config


I guess it boils down to these commits:

0a529da8cfe3 Merge branch 'net-stmmac-improbe-suspend-resume-architecture'
d6e1f2272960 net: stmmac: mediatek: convert to resume() method
c7308b2f3d0d net: stmmac: stm32: convert to suspend()/resume() methods
d7a276a5768f net: stmmac: rk: convert to suspend()/resume() methods
c91918a1e976 net: stmmac: pci: convert to suspend()/resume() methods
38772638d6d1 net: stmmac: loongson: convert to suspend()/resume() methods
062b42801733 net: stmmac: intel: convert to suspend()/resume() methods
b51f34bc85e3 net: stmmac: platform: legacy hooks for suspend()/resume() methods
7e84b3fae58c net: stmmac: provide a set of simple PM ops
07bbbfe7addf net: stmmac: add suspend()/resume() platform ops

CONFIG_PM is not defined on s390 and as result stmmac_simple_pm_ops ends up
in _DISCARD_PM_OPS(). The below patch fixes the linking, but it is by no
means a correct solution:

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c
index 5769165ee5ba..d475a77e4871 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c
@@ -668,7 +668,7 @@ static struct pci_driver loongson_dwmac_driver = {
 	.probe = loongson_dwmac_probe,
 	.remove = loongson_dwmac_remove,
 	.driver = {
-		.pm = &stmmac_simple_pm_ops,
+		.pm = &__static_stmmac_simple_pm_ops,
 	},
 };
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
index ac8288301994..69fcc8f10ccc 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
@@ -1820,7 +1820,7 @@ static struct platform_driver rk_gmac_dwmac_driver = {
 	.remove = rk_gmac_remove,
 	.driver = {
 		.name           = "rk_gmac-dwmac",
-		.pm		= &stmmac_simple_pm_ops,
+		.pm		= &__static_stmmac_simple_pm_ops,
 		.of_match_table = rk_gmac_dwmac_match,
 	},
 };
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
index 77a04c4579c9..d3e1eb35b231 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
@@ -669,7 +669,7 @@ static struct platform_driver stm32_dwmac_driver = {
 	.remove = stm32_dwmac_remove,
 	.driver = {
 		.name           = "stm32-dwmac",
-		.pm		= &stmmac_simple_pm_ops,
+		.pm		= &__static_stmmac_simple_pm_ops,
 		.of_match_table = stm32_dwmac_match,
 	},
 };
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index bf95f03dd33f..c5554ede0ba4 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
@@ -375,6 +375,7 @@ enum stmmac_state {
 };
 
 extern const struct dev_pm_ops stmmac_simple_pm_ops;
+extern const struct dev_pm_ops __static_stmmac_simple_pm_ops;
 
 int stmmac_mdio_unregister(struct net_device *ndev);
 int stmmac_mdio_register(struct net_device *ndev);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
index e6a7d0ddac2a..d1710f26d65a 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c
@@ -286,7 +286,7 @@ static struct pci_driver stmmac_pci_driver = {
 	.probe = stmmac_pci_probe,
 	.remove = stmmac_pci_remove,
 	.driver         = {
-		.pm     = &stmmac_simple_pm_ops,
+		.pm     = &__static_stmmac_simple_pm_ops,
 	},
 };
 
diff --git a/include/linux/pm.h b/include/linux/pm.h
index cc7b2dc28574..05524761fd51 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -381,7 +381,7 @@ const struct dev_pm_ops name = { \
 	const struct dev_pm_ops name
 
 #define _DISCARD_PM_OPS(name, license, ns)				\
-	static __maybe_unused const struct dev_pm_ops __static_##name
+	__maybe_unused const struct dev_pm_ops __static_##name
 
 #ifdef CONFIG_PM
 #define _EXPORT_DEV_PM_OPS(name, license, ns)		_EXPORT_PM_OPS(name, license, ns)


> --
> Linaro LKFT
> https://lkft.linaro.org

Re: next-20250813 s390 allyesconfig undefined reference to `stmmac_simple_pm_ops'

[Arnd Bergmann]

On Tue, Aug 19, 2025, at 18:00, Alexander Gordeev wrote:
> On Tue, Aug 19, 2025 at 03:07:56PM +0530, Naresh Kamboju wrote:
> CONFIG_PM is not defined on s390 and as result stmmac_simple_pm_ops ends up
> in _DISCARD_PM_OPS(). The below patch fixes the linking, but it is by no
> means a correct solution:
>
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c 
> b/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c
> index 5769165ee5ba..d475a77e4871 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c
> @@ -668,7 +668,7 @@ static struct pci_driver loongson_dwmac_driver = {
>  	.probe = loongson_dwmac_probe,
>  	.remove = loongson_dwmac_remove,
>  	.driver = {
> -		.pm = &stmmac_simple_pm_ops,
> +		.pm = &__static_stmmac_simple_pm_ops,

The correct solution is to make the PM_SLEEP versions use this

            .pm = pm_sleep_ptr(stmmac_simple_pm_ops),

or the corresponding version for the PM_RUNTIME+PM_SLEEP drivers:

            .pm = pm_ptr(stmmac_pltfrm_pm_ops),
 
By convention, the pm_ptr()/pm_sleep_ptr() macro should be
used for any driver using DEFINE_DEV_PM_OPS() or its variants,
though missing that does not produce a warning for non-exported
options and only wastes a few bytes of .data.

>  #define _DISCARD_PM_OPS(name, license, ns)				\
> -	static __maybe_unused const struct dev_pm_ops __static_##name
> +	__maybe_unused const struct dev_pm_ops __static_##name 

This would cause a lot of link failures elsewhere, since _DISCARD_PM_OPS
needs to ensure the operations are discarded by the compiler, which does
not happen when they are defined as a global symbol.

The idea of making this a 'static __maybe_unused' symbol is that
the actual functions get discarded as well but don't need an individual
__maybe_unused annotation or an #ifdef around them to prevent a
warning for unused symbols.

     Arnd