[PATCH] ahci: unregister acpi notify handler when a ZPODD is unbound

[PATCH] ahci: unregister acpi notify handler when a ZPODD is unbound

[Levente Kurusa]

When a ZPODD device is unbound via sysfs, the acpi notify handler
is not removed. This causes panics as observed in Bug #74601. The
panic only happens when the wake happens from outside the kernel
(i.e. inserting media or pressing a button). Implement a new
ahci_remove_one function which causes zpodd_exit to be called for all
ZPODD devices on the unbound PCI device.

Signed-off-by: Levente Kurusa <levex@linux.com>
---

Hi,

I am not sure if the loop below is correct. Maybe there is a better
solution to loop through all the devices which might use ZPODD?

Thanks, Lev.

 drivers/ata/ahci.c         | 21 +++++++++++++++++++++
 drivers/ata/ahci.h         |  4 ++++
 drivers/ata/libata-zpodd.c |  1 +
 3 files changed, 26 insertions(+)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 5a0bf8e..6d92bc9 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -475,12 +475,33 @@ static const struct pci_device_id ahci_pci_tbl[] = {
 	{ }	/* terminate list */
 };
 
+#ifdef CONFIG_SATA_ZPODD
+void ahci_remove_one(struct pci_dev *pdev)
+{
+	struct ata_host *host = pci_get_drvdata(pdev);
+	struct ata_link *link;
+	struct ata_device *dev;
+	int i;
+
+	for (i = 0; i < host->n_ports; i++)
+		ata_for_each_link(link, host->ports[i], HOST_FIRST)
+			ata_for_each_dev(dev, link, ALL)
+				if (dev->zpodd)
+					zpodd_exit(dev);
+
+	ata_pci_remove_one(pdev);
+}
+#endif
 
 static struct pci_driver ahci_pci_driver = {
 	.name			= DRV_NAME,
 	.id_table		= ahci_pci_tbl,
 	.probe			= ahci_init_one,
+#ifdef CONFIG_SATA_ZPODD
+	.remove			= ahci_remove_one,
+#else
 	.remove			= ata_pci_remove_one,
+#endif
 #ifdef CONFIG_PM
 	.suspend		= ahci_pci_device_suspend,
 	.resume			= ahci_pci_device_resume,
diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 51af275..87e4e6d 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -383,6 +383,10 @@ void ahci_print_info(struct ata_host *host, const char *scc_s);
 int ahci_host_activate(struct ata_host *host, int irq, unsigned int n_msis);
 void ahci_error_handler(struct ata_port *ap);
 
+#ifdef CONFIG_SATA_ZPODD
+extern void zpodd_exit(struct ata_device *dev);
+#endif /* CONFIG_SATA_ZPODD */
+
 static inline void __iomem *__ahci_port_base(struct ata_host *host,
 					     unsigned int port_no)
 {
diff --git a/drivers/ata/libata-zpodd.c b/drivers/ata/libata-zpodd.c
index f3a65a3..fe66949 100644
--- a/drivers/ata/libata-zpodd.c
+++ b/drivers/ata/libata-zpodd.c
@@ -281,3 +281,4 @@ void zpodd_exit(struct ata_device *dev)
 	kfree(dev->zpodd);
 	dev->zpodd = NULL;
 }
+EXPORT_SYMBOL_GPL(zpodd_exit);
-- 
1.8.3.1

Re: [PATCH] ahci: unregister acpi notify handler when a ZPODD is unbound

[Bartlomiej Zolnierkiewicz]

Hi,

On Wednesday, April 30, 2014 06:04:47 PM Levente Kurusa wrote:
> When a ZPODD device is unbound via sysfs, the acpi notify handler
> is not removed. This causes panics as observed in Bug #74601. The
> panic only happens when the wake happens from outside the kernel
> (i.e. inserting media or pressing a button). Implement a new
> ahci_remove_one function which causes zpodd_exit to be called for all
> ZPODD devices on the unbound PCI device.
> 
> Signed-off-by: Levente Kurusa <levex@linux.com>
> ---
> 
> Hi,
> 
> I am not sure if the loop below is correct. Maybe there is a better
> solution to loop through all the devices which might use ZPODD?
> 
> Thanks, Lev.
> 
>  drivers/ata/ahci.c         | 21 +++++++++++++++++++++
>  drivers/ata/ahci.h         |  4 ++++
>  drivers/ata/libata-zpodd.c |  1 +
>  3 files changed, 26 insertions(+)
> 
> diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
> index 5a0bf8e..6d92bc9 100644
> --- a/drivers/ata/ahci.c
> +++ b/drivers/ata/ahci.c
> @@ -475,12 +475,33 @@ static const struct pci_device_id ahci_pci_tbl[] = {
>  	{ }	/* terminate list */
>  };
>  
> +#ifdef CONFIG_SATA_ZPODD
> +void ahci_remove_one(struct pci_dev *pdev)
> +{
> +	struct ata_host *host = pci_get_drvdata(pdev);
> +	struct ata_link *link;
> +	struct ata_device *dev;
> +	int i;
> +
> +	for (i = 0; i < host->n_ports; i++)
> +		ata_for_each_link(link, host->ports[i], HOST_FIRST)
> +			ata_for_each_dev(dev, link, ALL)
> +				if (dev->zpodd)
> +					zpodd_exit(dev);

zpodd_init() is used in generic libata library code, same should be true
for zpodd_exit().  Ideally, you should find some libata library function
called from ata_pci_remove_one() suitable for this purpose.

Hmm, actually zpodd_exit() is already used in ata_scsi_handle_link_detach()
so this should also be taken into consideration..

> +	ata_pci_remove_one(pdev);
> +}
> +#endif
>  
>  static struct pci_driver ahci_pci_driver = {
>  	.name			= DRV_NAME,
>  	.id_table		= ahci_pci_tbl,
>  	.probe			= ahci_init_one,
> +#ifdef CONFIG_SATA_ZPODD
> +	.remove			= ahci_remove_one,
> +#else
>  	.remove			= ata_pci_remove_one,
> +#endif
>  #ifdef CONFIG_PM
>  	.suspend		= ahci_pci_device_suspend,
>  	.resume			= ahci_pci_device_resume,
> diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
> index 51af275..87e4e6d 100644
> --- a/drivers/ata/ahci.h
> +++ b/drivers/ata/ahci.h
> @@ -383,6 +383,10 @@ void ahci_print_info(struct ata_host *host, const char *scc_s);
>  int ahci_host_activate(struct ata_host *host, int irq, unsigned int n_msis);
>  void ahci_error_handler(struct ata_port *ap);
>  
> +#ifdef CONFIG_SATA_ZPODD
> +extern void zpodd_exit(struct ata_device *dev);
> +#endif /* CONFIG_SATA_ZPODD */
> +
>  static inline void __iomem *__ahci_port_base(struct ata_host *host,
>  					     unsigned int port_no)
>  {
> diff --git a/drivers/ata/libata-zpodd.c b/drivers/ata/libata-zpodd.c
> index f3a65a3..fe66949 100644
> --- a/drivers/ata/libata-zpodd.c
> +++ b/drivers/ata/libata-zpodd.c
> @@ -281,3 +281,4 @@ void zpodd_exit(struct ata_device *dev)
>  	kfree(dev->zpodd);
>  	dev->zpodd = NULL;
>  }
> +EXPORT_SYMBOL_GPL(zpodd_exit);

Then you would also not need to export zpodd_exit()..

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

Re: [PATCH] ahci: unregister acpi notify handler when a ZPODD is unbound

[Aaron Lu]

On 05/01/2014 12:04 AM, Levente Kurusa wrote:
> When a ZPODD device is unbound via sysfs, the acpi notify handler
> is not removed. This causes panics as observed in Bug #74601. The

Ah...too bad, I forgot to consider this situation, thanks for tracking
this.

> panic only happens when the wake happens from outside the kernel
> (i.e. inserting media or pressing a button). Implement a new
> ahci_remove_one function which causes zpodd_exit to be called for all
> ZPODD devices on the unbound PCI device.
> 
> Signed-off-by: Levente Kurusa <levex@linux.com>
> ---
> 
> Hi,
> 
> I am not sure if the loop below is correct. Maybe there is a better
> solution to loop through all the devices which might use ZPODD?

I didn't find a proper place either. For hotplug, we did the zpodd_exit
at ata_scsi_handle_link_detach. But for host controller pci device
removal, we used scsi_remove_host in ata_port_detach and there is no
place to add the zpodd_exit for a to-be-removed scsi device...

Looks like we can only iterate the ata devices and call zpodd_exit
explicitly for them if they are zpodd devices. Instead of adding a new
remove callback, what about just embed that into the ata_port_detach
like the following example?


diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 943cc8b83e59..43652da6fea6 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -6314,6 +6314,8 @@ int ata_host_activate(struct ata_host *host, int irq,
 static void ata_port_detach(struct ata_port *ap)
 {
 	unsigned long flags;
+	struct ata_link *link;
+	struct ata_device *dev;
 
 	if (!ap->ops->error_handler)
 		goto skip_eh;
@@ -6333,6 +6335,13 @@ static void ata_port_detach(struct ata_port *ap)
 	cancel_delayed_work_sync(&ap->hotplug_task);
 
  skip_eh:
+	/* clean up zpodd related stuffs on port removal */
+	ata_for_each_link(link, ap, HOST_FIRST) {
+		ata_for_each_dev(dev, link, ALL) {
+			if (zpodd_dev_enabled(dev))
+				zpodd_exit(dev);
+		}
+	}
 	if (ap->pmp_link) {
 		int i;
 		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)

Thanks,
Aaron

> 
> Thanks, Lev.
> 
>  drivers/ata/ahci.c         | 21 +++++++++++++++++++++
>  drivers/ata/ahci.h         |  4 ++++
>  drivers/ata/libata-zpodd.c |  1 +
>  3 files changed, 26 insertions(+)
> 
> diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
> index 5a0bf8e..6d92bc9 100644
> --- a/drivers/ata/ahci.c
> +++ b/drivers/ata/ahci.c
> @@ -475,12 +475,33 @@ static const struct pci_device_id ahci_pci_tbl[] = {
>  	{ }	/* terminate list */
>  };
>  
> +#ifdef CONFIG_SATA_ZPODD
> +void ahci_remove_one(struct pci_dev *pdev)
> +{
> +	struct ata_host *host = pci_get_drvdata(pdev);
> +	struct ata_link *link;
> +	struct ata_device *dev;
> +	int i;
> +
> +	for (i = 0; i < host->n_ports; i++)
> +		ata_for_each_link(link, host->ports[i], HOST_FIRST)
> +			ata_for_each_dev(dev, link, ALL)
> +				if (dev->zpodd)
> +					zpodd_exit(dev);
> +
> +	ata_pci_remove_one(pdev);
> +}
> +#endif
>  
>  static struct pci_driver ahci_pci_driver = {
>  	.name			= DRV_NAME,
>  	.id_table		= ahci_pci_tbl,
>  	.probe			= ahci_init_one,
> +#ifdef CONFIG_SATA_ZPODD
> +	.remove			= ahci_remove_one,
> +#else
>  	.remove			= ata_pci_remove_one,
> +#endif
>  #ifdef CONFIG_PM
>  	.suspend		= ahci_pci_device_suspend,
>  	.resume			= ahci_pci_device_resume,
> diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
> index 51af275..87e4e6d 100644
> --- a/drivers/ata/ahci.h
> +++ b/drivers/ata/ahci.h
> @@ -383,6 +383,10 @@ void ahci_print_info(struct ata_host *host, const char *scc_s);
>  int ahci_host_activate(struct ata_host *host, int irq, unsigned int n_msis);
>  void ahci_error_handler(struct ata_port *ap);
>  
> +#ifdef CONFIG_SATA_ZPODD
> +extern void zpodd_exit(struct ata_device *dev);
> +#endif /* CONFIG_SATA_ZPODD */
> +
>  static inline void __iomem *__ahci_port_base(struct ata_host *host,
>  					     unsigned int port_no)
>  {
> diff --git a/drivers/ata/libata-zpodd.c b/drivers/ata/libata-zpodd.c
> index f3a65a3..fe66949 100644
> --- a/drivers/ata/libata-zpodd.c
> +++ b/drivers/ata/libata-zpodd.c
> @@ -281,3 +281,4 @@ void zpodd_exit(struct ata_device *dev)
>  	kfree(dev->zpodd);
>  	dev->zpodd = NULL;
>  }
> +EXPORT_SYMBOL_GPL(zpodd_exit);
> 

Re: [PATCH] ahci: unregister acpi notify handler when a ZPODD is unbound

[Levente Kurusa]

[-- Attachment #1: Type: text/plain, Size: 2528 bytes --]

Hi,

On 05/06/2014 05:16 AM, Aaron Lu wrote:
> On 05/01/2014 12:04 AM, Levente Kurusa wrote:
>> When a ZPODD device is unbound via sysfs, the acpi notify handler
>> is not removed. This causes panics as observed in Bug #74601. The
> 
> Ah...too bad, I forgot to consider this situation, thanks for tracking
> this.
> 
>> panic only happens when the wake happens from outside the kernel
>> (i.e. inserting media or pressing a button). Implement a new
>> ahci_remove_one function which causes zpodd_exit to be called for all
>> ZPODD devices on the unbound PCI device.
>>
>> Signed-off-by: Levente Kurusa <levex@linux.com>
>> ---
>>
>> Hi,
>>
>> I am not sure if the loop below is correct. Maybe there is a better
>> solution to loop through all the devices which might use ZPODD?
> 
> I didn't find a proper place either. For hotplug, we did the zpodd_exit
> at ata_scsi_handle_link_detach. But for host controller pci device
> removal, we used scsi_remove_host in ata_port_detach and there is no
> place to add the zpodd_exit for a to-be-removed scsi device...
> 
> Looks like we can only iterate the ata devices and call zpodd_exit
> explicitly for them if they are zpodd devices. Instead of adding a new
> remove callback, what about just embed that into the ata_port_detach
> like the following example?

Yes, this makes more sense as this doesn't tinker with exports and such...
However this will throw unused variable compiler warnings if we add the
required #ifdefs... Maybe a new function? ata_zpodd_detach_port?

> 
> 
> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
> index 943cc8b83e59..43652da6fea6 100644
> --- a/drivers/ata/libata-core.c
> +++ b/drivers/ata/libata-core.c
> @@ -6314,6 +6314,8 @@ int ata_host_activate(struct ata_host *host, int irq,
>  static void ata_port_detach(struct ata_port *ap)
>  {
>  	unsigned long flags;
> +	struct ata_link *link;
> +	struct ata_device *dev;
>  
>  	if (!ap->ops->error_handler)
>  		goto skip_eh;
> @@ -6333,6 +6335,13 @@ static void ata_port_detach(struct ata_port *ap)
>  	cancel_delayed_work_sync(&ap->hotplug_task);
>  
>   skip_eh:
> +	/* clean up zpodd related stuffs on port removal */
> +	ata_for_each_link(link, ap, HOST_FIRST) {
> +		ata_for_each_dev(dev, link, ALL) {
> +			if (zpodd_dev_enabled(dev))
> +				zpodd_exit(dev);
> +		}
> +	}
>  	if (ap->pmp_link) {
>  		int i;
>  		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)

-- 
Regards,
Levente Kurusa
PGP: 4EF5D641


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 555 bytes --]

Re: [PATCH] ahci: unregister acpi notify handler when a ZPODD is unbound

[Aaron Lu]

On 05/06/2014 02:02 PM, Levente Kurusa wrote:
> Hi,
> 
> On 05/06/2014 05:16 AM, Aaron Lu wrote:
>> On 05/01/2014 12:04 AM, Levente Kurusa wrote:
>>> When a ZPODD device is unbound via sysfs, the acpi notify handler
>>> is not removed. This causes panics as observed in Bug #74601. The
>>
>> Ah...too bad, I forgot to consider this situation, thanks for tracking
>> this.
>>
>>> panic only happens when the wake happens from outside the kernel
>>> (i.e. inserting media or pressing a button). Implement a new
>>> ahci_remove_one function which causes zpodd_exit to be called for all
>>> ZPODD devices on the unbound PCI device.
>>>
>>> Signed-off-by: Levente Kurusa <levex@linux.com>
>>> ---
>>>
>>> Hi,
>>>
>>> I am not sure if the loop below is correct. Maybe there is a better
>>> solution to loop through all the devices which might use ZPODD?
>>
>> I didn't find a proper place either. For hotplug, we did the zpodd_exit
>> at ata_scsi_handle_link_detach. But for host controller pci device
>> removal, we used scsi_remove_host in ata_port_detach and there is no
>> place to add the zpodd_exit for a to-be-removed scsi device...
>>
>> Looks like we can only iterate the ata devices and call zpodd_exit
>> explicitly for them if they are zpodd devices. Instead of adding a new
>> remove callback, what about just embed that into the ata_port_detach
>> like the following example?
> 
> Yes, this makes more sense as this doesn't tinker with exports and such...
> However this will throw unused variable compiler warnings if we add the
> required #ifdefs... Maybe a new function? ata_zpodd_detach_port?

I think we can omit the #ifdefs as the loop is not called frequently and
thus doesn't cost much. We already have stubs for zpodd_dev_enabled and
zpodd_exit.

Thanks,
Aaron

> 
>>
>>
>> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
>> index 943cc8b83e59..43652da6fea6 100644
>> --- a/drivers/ata/libata-core.c
>> +++ b/drivers/ata/libata-core.c
>> @@ -6314,6 +6314,8 @@ int ata_host_activate(struct ata_host *host, int irq,
>>  static void ata_port_detach(struct ata_port *ap)
>>  {
>>  	unsigned long flags;
>> +	struct ata_link *link;
>> +	struct ata_device *dev;
>>  
>>  	if (!ap->ops->error_handler)
>>  		goto skip_eh;
>> @@ -6333,6 +6335,13 @@ static void ata_port_detach(struct ata_port *ap)
>>  	cancel_delayed_work_sync(&ap->hotplug_task);
>>  
>>   skip_eh:
>> +	/* clean up zpodd related stuffs on port removal */
>> +	ata_for_each_link(link, ap, HOST_FIRST) {
>> +		ata_for_each_dev(dev, link, ALL) {
>> +			if (zpodd_dev_enabled(dev))
>> +				zpodd_exit(dev);
>> +		}
>> +	}
>>  	if (ap->pmp_link) {
>>  		int i;
>>  		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
> 

Re: [PATCH] ahci: unregister acpi notify handler when a ZPODD is unbound

[Levente Kurusa]

[-- Attachment #1: Type: text/plain, Size: 2012 bytes --]

Hi,

On 05/06/2014 08:07 AM, Aaron Lu wrote:
> On 05/06/2014 02:02 PM, Levente Kurusa wrote:
>> Hi,
>>
>> On 05/06/2014 05:16 AM, Aaron Lu wrote:
>>> On 05/01/2014 12:04 AM, Levente Kurusa wrote:
>>>> When a ZPODD device is unbound via sysfs, the acpi notify handler
>>>> is not removed. This causes panics as observed in Bug #74601. The
>>>
>>> Ah...too bad, I forgot to consider this situation, thanks for tracking
>>> this.
>>>
>>>> panic only happens when the wake happens from outside the kernel
>>>> (i.e. inserting media or pressing a button). Implement a new
>>>> ahci_remove_one function which causes zpodd_exit to be called for all
>>>> ZPODD devices on the unbound PCI device.
>>>>
>>>> Signed-off-by: Levente Kurusa <levex@linux.com>
>>>> ---
>>>>
>>>> Hi,
>>>>
>>>> I am not sure if the loop below is correct. Maybe there is a better
>>>> solution to loop through all the devices which might use ZPODD?
>>>
>>> I didn't find a proper place either. For hotplug, we did the zpodd_exit
>>> at ata_scsi_handle_link_detach. But for host controller pci device
>>> removal, we used scsi_remove_host in ata_port_detach and there is no
>>> place to add the zpodd_exit for a to-be-removed scsi device...
>>>
>>> Looks like we can only iterate the ata devices and call zpodd_exit
>>> explicitly for them if they are zpodd devices. Instead of adding a new
>>> remove callback, what about just embed that into the ata_port_detach
>>> like the following example?
>>
>> Yes, this makes more sense as this doesn't tinker with exports and such...
>> However this will throw unused variable compiler warnings if we add the
>> required #ifdefs... Maybe a new function? ata_zpodd_detach_port?
> 
> I think we can omit the #ifdefs as the loop is not called frequently and
> thus doesn't cost much. We already have stubs for zpodd_dev_enabled and
> zpodd_exit.
> 

Ah, I see. Shall I send V2? Any tags I should add for you?

-- 
Regards,
Levente Kurusa
PGP: 4EF5D641


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 555 bytes --]

Re: [PATCH] ahci: unregister acpi notify handler when a ZPODD is unbound

[Aaron Lu]

On 05/06/2014 03:14 PM, Levente Kurusa wrote:
> Hi,
> 
> On 05/06/2014 08:07 AM, Aaron Lu wrote:
>> On 05/06/2014 02:02 PM, Levente Kurusa wrote:
>>> Hi,
>>>
>>> On 05/06/2014 05:16 AM, Aaron Lu wrote:
>>>> On 05/01/2014 12:04 AM, Levente Kurusa wrote:
>>>>> When a ZPODD device is unbound via sysfs, the acpi notify handler
>>>>> is not removed. This causes panics as observed in Bug #74601. The
>>>>
>>>> Ah...too bad, I forgot to consider this situation, thanks for tracking
>>>> this.
>>>>
>>>>> panic only happens when the wake happens from outside the kernel
>>>>> (i.e. inserting media or pressing a button). Implement a new
>>>>> ahci_remove_one function which causes zpodd_exit to be called for all
>>>>> ZPODD devices on the unbound PCI device.
>>>>>
>>>>> Signed-off-by: Levente Kurusa <levex@linux.com>
>>>>> ---
>>>>>
>>>>> Hi,
>>>>>
>>>>> I am not sure if the loop below is correct. Maybe there is a better
>>>>> solution to loop through all the devices which might use ZPODD?
>>>>
>>>> I didn't find a proper place either. For hotplug, we did the zpodd_exit
>>>> at ata_scsi_handle_link_detach. But for host controller pci device
>>>> removal, we used scsi_remove_host in ata_port_detach and there is no
>>>> place to add the zpodd_exit for a to-be-removed scsi device...
>>>>
>>>> Looks like we can only iterate the ata devices and call zpodd_exit
>>>> explicitly for them if they are zpodd devices. Instead of adding a new
>>>> remove callback, what about just embed that into the ata_port_detach
>>>> like the following example?
>>>
>>> Yes, this makes more sense as this doesn't tinker with exports and such...
>>> However this will throw unused variable compiler warnings if we add the
>>> required #ifdefs... Maybe a new function? ata_zpodd_detach_port?
>>
>> I think we can omit the #ifdefs as the loop is not called frequently and
>> thus doesn't cost much. We already have stubs for zpodd_dev_enabled and
>> zpodd_exit.
>>
> 
> Ah, I see. Shall I send V2? Any tags I should add for you?

Yes please. Also, this seems to be stable candidate.
You can add my reviewed-by tag, thanks.