[3.13,061/259] thermal: hwmon: Make the check for critical temp valid consistent

3.13.11.6 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Aaron Lu <aaron.lu@intel.com>

commit e8db5d6736a712a3e2280c0e31f4b301d85172d8 upstream.

On 05/21/2014 04:22 PM, Aaron Lu wrote:
> On 05/21/2014 01:57 PM, Kui Zhang wrote:
>> Hello,
>>
>> I get following error when rmmod thermal.
>>
>> rmmod  thermal
>> Killed

While dealing with this problem, I found another problem that also
results in a kernel crash on thermal module removal:

From: Aaron Lu <aaron.lu@intel.com>
Date: Wed, 21 May 2014 16:05:38 +0800
Subject: [PATCH] thermal: hwmon: Make the check for critical temp valid consistent

We used the tz->ops->get_crit_temp && !tz->ops->get_crit_temp(tz, temp)
to decide if we need to create the temp_crit attribute file but we just
check if tz->ops->get_crit_temp exists to decide if we need to remove
that attribute file. Some ACPI thermal zone doesn't have a valid critical
trip point and that would result in removing a non-existent device file
on thermal module unload.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 drivers/thermal/thermal_hwmon.c | 33 ++++++++++++++++++---------------
 1 file changed, 18 insertions(+), 15 deletions(-)

Hello,

On Fri, Aug 8, 2014 at 4:38 PM, Kamal Mostafa <kamal@canonical.com> wrote:
> 3.13.11.6 -stable review patch.  If anyone has any objections, please let me know.
>
> ------------------
>
> From: Aaron Lu <aaron.lu@intel.com>
>
> commit e8db5d6736a712a3e2280c0e31f4b301d85172d8 upstream.
>
> On 05/21/2014 04:22 PM, Aaron Lu wrote:
>> On 05/21/2014 01:57 PM, Kui Zhang wrote:
>>> Hello,
>>>
>>> I get following error when rmmod thermal.
>>>
>>> rmmod  thermal
>>> Killed
>
> While dealing with this problem, I found another problem that also
> results in a kernel crash on thermal module removal:
>
> From: Aaron Lu <aaron.lu@intel.com>
> Date: Wed, 21 May 2014 16:05:38 +0800
> Subject: [PATCH] thermal: hwmon: Make the check for critical temp valid consistent
>
> We used the tz->ops->get_crit_temp && !tz->ops->get_crit_temp(tz, temp)
> to decide if we need to create the temp_crit attribute file but we just
> check if tz->ops->get_crit_temp exists to decide if we need to remove
> that attribute file. Some ACPI thermal zone doesn't have a valid critical
> trip point and that would result in removing a non-existent device file
> on thermal module unload.
>
> Signed-off-by: Aaron Lu <aaron.lu@intel.com>
> Signed-off-by: Zhang Rui <rui.zhang@intel.com>
> Signed-off-by: Kamal Mostafa <kamal@canonical.com>

Acked-by: Eduardo Valentin <edubezval@gmail.com>

> ---
>  drivers/thermal/thermal_hwmon.c | 33 ++++++++++++++++++---------------
>  1 file changed, 18 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/thermal/thermal_hwmon.c b/drivers/thermal/thermal_hwmon.c
> index fdb0719..1967bee 100644
> --- a/drivers/thermal/thermal_hwmon.c
> +++ b/drivers/thermal/thermal_hwmon.c
> @@ -140,6 +140,12 @@ thermal_hwmon_lookup_temp(const struct thermal_hwmon_device *hwmon,
>         return NULL;
>  }
>
> +static bool thermal_zone_crit_temp_valid(struct thermal_zone_device *tz)
> +{
> +       unsigned long temp;
> +       return tz->ops->get_crit_temp && !tz->ops->get_crit_temp(tz, &temp);
> +}
> +
>  int thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
>  {
>         struct thermal_hwmon_device *hwmon;
> @@ -189,21 +195,18 @@ int thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
>         if (result)
>                 goto free_temp_mem;
>
> -       if (tz->ops->get_crit_temp) {
> -               unsigned long temperature;
> -               if (!tz->ops->get_crit_temp(tz, &temperature)) {
> -                       snprintf(temp->temp_crit.name,
> -                                sizeof(temp->temp_crit.name),
> +       if (thermal_zone_crit_temp_valid(tz)) {
> +               snprintf(temp->temp_crit.name,
> +                               sizeof(temp->temp_crit.name),
>                                 "temp%d_crit", hwmon->count);
> -                       temp->temp_crit.attr.attr.name = temp->temp_crit.name;
> -                       temp->temp_crit.attr.attr.mode = 0444;
> -                       temp->temp_crit.attr.show = temp_crit_show;
> -                       sysfs_attr_init(&temp->temp_crit.attr.attr);
> -                       result = device_create_file(hwmon->device,
> -                                                   &temp->temp_crit.attr);
> -                       if (result)
> -                               goto unregister_input;
> -               }
> +               temp->temp_crit.attr.attr.name = temp->temp_crit.name;
> +               temp->temp_crit.attr.attr.mode = 0444;
> +               temp->temp_crit.attr.show = temp_crit_show;
> +               sysfs_attr_init(&temp->temp_crit.attr.attr);
> +               result = device_create_file(hwmon->device,
> +                                           &temp->temp_crit.attr);
> +               if (result)
> +                       goto unregister_input;
>         }
>
>         mutex_lock(&thermal_hwmon_list_lock);
> @@ -250,7 +253,7 @@ void thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
>         }
>
>         device_remove_file(hwmon->device, &temp->temp_input.attr);
> -       if (tz->ops->get_crit_temp)
> +       if (thermal_zone_crit_temp_valid(tz))
>                 device_remove_file(hwmon->device, &temp->temp_crit.attr);
>
>         mutex_lock(&thermal_hwmon_list_lock);
> --
> 1.9.1
>
> --
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