[PATCH] drivers core: export symbols for device hotplug

[PATCH] drivers core: export symbols for device hotplug

[Chanho Park]

To support module build for cpu hotplug driver on type-1 hypervisor
such as drivers/xen/cpu_hotplug.c, we need to export below four symbols.

lock_device_hotplug / unlock_device_hotplug
device_online / device_offline

Signed-off-by: Chanho Park <chanho61.park@samsung.com>
---
 drivers/base/core.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index d661ada1518f..1bfd0c54a778 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -1586,11 +1586,13 @@ void lock_device_hotplug(void)
 {
 	mutex_lock(&device_hotplug_lock);
 }
+EXPORT_SYMBOL_GPL(lock_device_hotplug);
 
 void unlock_device_hotplug(void)
 {
 	mutex_unlock(&device_hotplug_lock);
 }
+EXPORT_SYMBOL_GPL(unlock_device_hotplug);
 
 int lock_device_hotplug_sysfs(void)
 {
@@ -3419,6 +3421,7 @@ int device_offline(struct device *dev)
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(device_offline);
 
 /**
  * device_online - Put the device back online after successful device_offline().
@@ -3450,6 +3453,7 @@ int device_online(struct device *dev)
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(device_online);
 
 struct root_device {
 	struct device dev;
-- 
2.23.0

Re: [PATCH] drivers core: export symbols for device hotplug

[Greg KH]

On Fri, Nov 27, 2020 at 12:01:38AM +0900, Chanho Park wrote:
> To support module build for cpu hotplug driver on type-1 hypervisor
> such as drivers/xen/cpu_hotplug.c, we need to export below four symbols.
> 
> lock_device_hotplug / unlock_device_hotplug
> device_online / device_offline
> 
> Signed-off-by: Chanho Park <chanho61.park@samsung.com>
> ---
>  drivers/base/core.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index d661ada1518f..1bfd0c54a778 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -1586,11 +1586,13 @@ void lock_device_hotplug(void)
>  {
>  	mutex_lock(&device_hotplug_lock);
>  }
> +EXPORT_SYMBOL_GPL(lock_device_hotplug);

Ick, really?  Anyway, where is the follow-on patch that uses this in a
module?  We need that in order to export these otherwise we will just
un-export them with no in-kernel users.

thanks,

greg k-h