Mailing List Archive

Modules registering driver with amba_driver_register() often forget to
set .owner field. The field is used by some of other kernel parts for
reference counting (try_module_get()), so it is expected that drivers
will set it.

Solve the problem by moving this task away from the drivers to the core
amba bus code, just like we did for platform_driver in
commit 9447057eaff8 ("platform_device: use a macro instead of
platform_driver_register").

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
drivers/amba/bus.c | 11 +++++++----
include/linux/amba/bus.h | 11 +++++++++--
2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index a24c152bfaac..aba3aa95b224 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -488,28 +488,31 @@ static int __init amba_stub_drv_init(void)
* waiting on amba_match(). So, register a stub driver to make sure
* amba_match() is called even if no amba driver has been registered.
*/
- return amba_driver_register(&amba_proxy_drv);
+ return __amba_driver_register(&amba_proxy_drv, NULL);
}
late_initcall_sync(amba_stub_drv_init);

/**
- * amba_driver_register - register an AMBA device driver
+ * __amba_driver_register - register an AMBA device driver
* @drv: amba device driver structure
+ * @owner: owning module/driver
*
* Register an AMBA device driver with the Linux device model
* core. If devices pre-exist, the drivers probe function will
* be called.
*/
-int amba_driver_register(struct amba_driver *drv)
+int __amba_driver_register(struct amba_driver *drv,
+ struct module *owner)
{
if (!drv->probe)
return -EINVAL;

+ drv->drv.owner = owner;
drv->drv.bus = &amba_bustype;

return driver_register(&drv->drv);
}
-EXPORT_SYMBOL(amba_driver_register);
+EXPORT_SYMBOL(__amba_driver_register);

/**
* amba_driver_unregister - remove an AMBA device driver
diff --git a/include/linux/amba/bus.h b/include/linux/amba/bus.h
index c60a6a14638c..958a55bcc708 100644
--- a/include/linux/amba/bus.h
+++ b/include/linux/amba/bus.h
@@ -112,11 +112,18 @@ extern struct bus_type amba_bustype;
#define amba_get_drvdata(d) dev_get_drvdata(&d->dev)
#define amba_set_drvdata(d,p) dev_set_drvdata(&d->dev, p)

+/*
+ * use a macro to avoid include chaining to get THIS_MODULE
+ */
+#define amba_driver_register(drv) \
+ __amba_driver_register(drv, THIS_MODULE)
+
#ifdef CONFIG_ARM_AMBA
-int amba_driver_register(struct amba_driver *);
+int __amba_driver_register(struct amba_driver *, struct module *);
void amba_driver_unregister(struct amba_driver *);
#else
-static inline int amba_driver_register(struct amba_driver *drv)
+static inline int __amba_driver_register(struct amba_driver *drv,
+ struct module *owner)
{
return -EINVAL;
}

--
2.34.1