[PATCH v2] Do not disable driver and bus shutdown hook when class shutdown hook is set.

[PATCH v2] Do not disable driver and bus shutdown hook when class shutdown hook is set.

[Michal Suchanek]

As seen from the implementation of the single class shutdown hook this
is not very sound design.

Rename the class shutdown hook to shutdown_pre to make it clear it runs
before the driver shutdown hook.

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
---
v2: rename class shutdown member to shutdown_pre
---
 drivers/base/core.c         |  9 +++++----
 drivers/char/tpm/tpm-chip.c | 11 ++---------
 include/linux/device.h      |  4 ++--
 3 files changed, 9 insertions(+), 15 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 755451f684bc..13e7c41fd417 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -2664,11 +2664,12 @@ void device_shutdown(void)
 		pm_runtime_get_noresume(dev);
 		pm_runtime_barrier(dev);
 
-		if (dev->class && dev->class->shutdown) {
+		if (dev->class && dev->class->shutdown_pre) {
 			if (initcall_debug)
-				dev_info(dev, "shutdown\n");
-			dev->class->shutdown(dev);
-		} else if (dev->bus && dev->bus->shutdown) {
+				dev_info(dev, "shutdown_pre\n");
+			dev->class->shutdown_pre(dev);
+		}
+		if (dev->bus && dev->bus->shutdown) {
 			if (initcall_debug)
 				dev_info(dev, "shutdown\n");
 			dev->bus->shutdown(dev);
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 67ec9d3d04f5..0eca20c5a80c 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -164,14 +164,7 @@ static int tpm_class_shutdown(struct device *dev)
 		chip->ops = NULL;
 		up_write(&chip->ops_sem);
 	}
-	/* Allow bus- and device-specific code to run. Note: since chip->ops
-	 * is NULL, more-specific shutdown code will not be able to issue TPM
-	 * commands.
-	 */
-	if (dev->bus && dev->bus->shutdown)
-		dev->bus->shutdown(dev);
-	else if (dev->driver && dev->driver->shutdown)
-		dev->driver->shutdown(dev);
+
 	return 0;
 }
 
@@ -214,7 +207,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
 	device_initialize(&chip->devs);
 
 	chip->dev.class = tpm_class;
-	chip->dev.class->shutdown = tpm_class_shutdown;
+	chip->dev.class->shutdown_pre = tpm_class_shutdown;
 	chip->dev.release = tpm_dev_release;
 	chip->dev.parent = pdev;
 	chip->dev.groups = chip->groups;
diff --git a/include/linux/device.h b/include/linux/device.h
index beabdbc08420..649b1b72c76a 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -375,7 +375,7 @@ int subsys_virtual_register(struct bus_type *subsys,
  * @suspend:	Used to put the device to sleep mode, usually to a low power
  *		state.
  * @resume:	Used to bring the device from the sleep mode.
- * @shutdown:	Called at shut-down time to quiesce the device.
+ * @shutdown_pre: Called at shut-down time before driver shutdown.
  * @ns_type:	Callbacks so sysfs can detemine namespaces.
  * @namespace:	Namespace of the device belongs to this class.
  * @pm:		The default device power management operations of this class.
@@ -404,7 +404,7 @@ struct class {
 
 	int (*suspend)(struct device *dev, pm_message_t state);
 	int (*resume)(struct device *dev);
-	int (*shutdown)(struct device *dev);
+	int (*shutdown_pre)(struct device *dev);
 
 	const struct kobj_ns_type_operations *ns_type;
 	const void *(*namespace)(struct device *dev);
-- 
2.10.2

Re: [PATCH v2] Do not disable driver and bus shutdown hook when class shutdown hook is set.

[Jarkko Sakkinen]

On Fri, Aug 11, 2017 at 03:44:43PM +0200, Michal Suchanek wrote:
> As seen from the implementation of the single class shutdown hook this
> is not very sound design.
> 
> Rename the class shutdown hook to shutdown_pre to make it clear it runs
> before the driver shutdown hook.
> 
> Signed-off-by: Michal Suchanek <msuchanek@suse.de>

Now, at least for me, this makes sense.

Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

/Jarkko

> ---
> v2: rename class shutdown member to shutdown_pre
> ---
>  drivers/base/core.c         |  9 +++++----
>  drivers/char/tpm/tpm-chip.c | 11 ++---------
>  include/linux/device.h      |  4 ++--
>  3 files changed, 9 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index 755451f684bc..13e7c41fd417 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -2664,11 +2664,12 @@ void device_shutdown(void)
>  		pm_runtime_get_noresume(dev);
>  		pm_runtime_barrier(dev);
>  
> -		if (dev->class && dev->class->shutdown) {
> +		if (dev->class && dev->class->shutdown_pre) {
>  			if (initcall_debug)
> -				dev_info(dev, "shutdown\n");
> -			dev->class->shutdown(dev);
> -		} else if (dev->bus && dev->bus->shutdown) {
> +				dev_info(dev, "shutdown_pre\n");
> +			dev->class->shutdown_pre(dev);
> +		}
> +		if (dev->bus && dev->bus->shutdown) {
>  			if (initcall_debug)
>  				dev_info(dev, "shutdown\n");
>  			dev->bus->shutdown(dev);
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index 67ec9d3d04f5..0eca20c5a80c 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -164,14 +164,7 @@ static int tpm_class_shutdown(struct device *dev)
>  		chip->ops = NULL;
>  		up_write(&chip->ops_sem);
>  	}
> -	/* Allow bus- and device-specific code to run. Note: since chip->ops
> -	 * is NULL, more-specific shutdown code will not be able to issue TPM
> -	 * commands.
> -	 */
> -	if (dev->bus && dev->bus->shutdown)
> -		dev->bus->shutdown(dev);
> -	else if (dev->driver && dev->driver->shutdown)
> -		dev->driver->shutdown(dev);
> +
>  	return 0;
>  }
>  
> @@ -214,7 +207,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
>  	device_initialize(&chip->devs);
>  
>  	chip->dev.class = tpm_class;
> -	chip->dev.class->shutdown = tpm_class_shutdown;
> +	chip->dev.class->shutdown_pre = tpm_class_shutdown;
>  	chip->dev.release = tpm_dev_release;
>  	chip->dev.parent = pdev;
>  	chip->dev.groups = chip->groups;
> diff --git a/include/linux/device.h b/include/linux/device.h
> index beabdbc08420..649b1b72c76a 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -375,7 +375,7 @@ int subsys_virtual_register(struct bus_type *subsys,
>   * @suspend:	Used to put the device to sleep mode, usually to a low power
>   *		state.
>   * @resume:	Used to bring the device from the sleep mode.
> - * @shutdown:	Called at shut-down time to quiesce the device.
> + * @shutdown_pre: Called at shut-down time before driver shutdown.
>   * @ns_type:	Callbacks so sysfs can detemine namespaces.
>   * @namespace:	Namespace of the device belongs to this class.
>   * @pm:		The default device power management operations of this class.
> @@ -404,7 +404,7 @@ struct class {
>  
>  	int (*suspend)(struct device *dev, pm_message_t state);
>  	int (*resume)(struct device *dev);
> -	int (*shutdown)(struct device *dev);
> +	int (*shutdown_pre)(struct device *dev);
>  
>  	const struct kobj_ns_type_operations *ns_type;
>  	const void *(*namespace)(struct device *dev);
> -- 
> 2.10.2
> 

Re: [PATCH v2] Do not disable driver and bus shutdown hook when class shutdown hook is set.

[Jarkko Sakkinen]

On Fri, Aug 11, 2017 at 03:44:43PM +0200, Michal Suchanek wrote:
> As seen from the implementation of the single class shutdown hook this
> is not very sound design.
> 
> Rename the class shutdown hook to shutdown_pre to make it clear it runs
> before the driver shutdown hook.
> 
> Signed-off-by: Michal Suchanek <msuchanek@suse.de>

I already gave this reviewed-by but cannot apply it because there's no
ack from device maintainers yet.

/Jarkko

> ---
> v2: rename class shutdown member to shutdown_pre
> ---
>  drivers/base/core.c         |  9 +++++----
>  drivers/char/tpm/tpm-chip.c | 11 ++---------
>  include/linux/device.h      |  4 ++--
>  3 files changed, 9 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index 755451f684bc..13e7c41fd417 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -2664,11 +2664,12 @@ void device_shutdown(void)
>  		pm_runtime_get_noresume(dev);
>  		pm_runtime_barrier(dev);
>  
> -		if (dev->class && dev->class->shutdown) {
> +		if (dev->class && dev->class->shutdown_pre) {
>  			if (initcall_debug)
> -				dev_info(dev, "shutdown\n");
> -			dev->class->shutdown(dev);
> -		} else if (dev->bus && dev->bus->shutdown) {
> +				dev_info(dev, "shutdown_pre\n");
> +			dev->class->shutdown_pre(dev);
> +		}
> +		if (dev->bus && dev->bus->shutdown) {
>  			if (initcall_debug)
>  				dev_info(dev, "shutdown\n");
>  			dev->bus->shutdown(dev);
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index 67ec9d3d04f5..0eca20c5a80c 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -164,14 +164,7 @@ static int tpm_class_shutdown(struct device *dev)
>  		chip->ops = NULL;
>  		up_write(&chip->ops_sem);
>  	}
> -	/* Allow bus- and device-specific code to run. Note: since chip->ops
> -	 * is NULL, more-specific shutdown code will not be able to issue TPM
> -	 * commands.
> -	 */
> -	if (dev->bus && dev->bus->shutdown)
> -		dev->bus->shutdown(dev);
> -	else if (dev->driver && dev->driver->shutdown)
> -		dev->driver->shutdown(dev);
> +
>  	return 0;
>  }
>  
> @@ -214,7 +207,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
>  	device_initialize(&chip->devs);
>  
>  	chip->dev.class = tpm_class;
> -	chip->dev.class->shutdown = tpm_class_shutdown;
> +	chip->dev.class->shutdown_pre = tpm_class_shutdown;
>  	chip->dev.release = tpm_dev_release;
>  	chip->dev.parent = pdev;
>  	chip->dev.groups = chip->groups;
> diff --git a/include/linux/device.h b/include/linux/device.h
> index beabdbc08420..649b1b72c76a 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -375,7 +375,7 @@ int subsys_virtual_register(struct bus_type *subsys,
>   * @suspend:	Used to put the device to sleep mode, usually to a low power
>   *		state.
>   * @resume:	Used to bring the device from the sleep mode.
> - * @shutdown:	Called at shut-down time to quiesce the device.
> + * @shutdown_pre: Called at shut-down time before driver shutdown.
>   * @ns_type:	Callbacks so sysfs can detemine namespaces.
>   * @namespace:	Namespace of the device belongs to this class.
>   * @pm:		The default device power management operations of this class.
> @@ -404,7 +404,7 @@ struct class {
>  
>  	int (*suspend)(struct device *dev, pm_message_t state);
>  	int (*resume)(struct device *dev);
> -	int (*shutdown)(struct device *dev);
> +	int (*shutdown_pre)(struct device *dev);
>  
>  	const struct kobj_ns_type_operations *ns_type;
>  	const void *(*namespace)(struct device *dev);
> -- 
> 2.10.2
> 

Re: [PATCH v2] Do not disable driver and bus shutdown hook when class shutdown hook is set.

[Greg Kroah-Hartman]

On Sat, Aug 19, 2017 at 03:03:53PM +0300, Jarkko Sakkinen wrote:
> On Fri, Aug 11, 2017 at 03:44:43PM +0200, Michal Suchanek wrote:
> > As seen from the implementation of the single class shutdown hook this
> > is not very sound design.
> > 
> > Rename the class shutdown hook to shutdown_pre to make it clear it runs
> > before the driver shutdown hook.
> > 
> > Signed-off-by: Michal Suchanek <msuchanek@suse.de>
> 
> I already gave this reviewed-by but cannot apply it because there's no
> ack from device maintainers yet.

I'm on vacation at the moment and will look at this when I get back in a
week, please give me a chance.

thanks,

greg k-h

Re: [PATCH v2] Do not disable driver and bus shutdown hook when class shutdown hook is set.

[Jarkko Sakkinen]

On Sat, Aug 19, 2017 at 10:03:40AM -0700, Greg Kroah-Hartman wrote:
> On Sat, Aug 19, 2017 at 03:03:53PM +0300, Jarkko Sakkinen wrote:
> > On Fri, Aug 11, 2017 at 03:44:43PM +0200, Michal Suchanek wrote:
> > > As seen from the implementation of the single class shutdown hook this
> > > is not very sound design.
> > > 
> > > Rename the class shutdown hook to shutdown_pre to make it clear it runs
> > > before the driver shutdown hook.
> > > 
> > > Signed-off-by: Michal Suchanek <msuchanek@suse.de>
> > 
> > I already gave this reviewed-by but cannot apply it because there's no
> > ack from device maintainers yet.
> 
> I'm on vacation at the moment and will look at this when I get back in a
> week, please give me a chance.
> 
> thanks,
> 
> greg k-h

Take your time! I don't think this patch is critical. Thanks.

/Jarkko