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authorArmin Wolf <W_Armin@gmx.de>2023-02-18 14:53:17 +0300
committerHans de Goede <hdegoede@redhat.com>2023-03-07 13:37:27 +0300
commit001f61c4688f1dad18cfaa35ae364b35fb3cd66c (patch)
treeda49d21a57d9e9c78c5f965c2126bf887c414a8a /drivers
parent24efcdf03d85bb73df0ba99f69c8d238e7ada0e5 (diff)
downloadlinux-001f61c4688f1dad18cfaa35ae364b35fb3cd66c.tar.xz
platform/x86: dell-ddv: Fix cache invalidation on resume
If one or both sensor buffers could not be initialized, either due to missing hardware support or due to some error during probing, the resume handler will encounter undefined behaviour when attempting to lock buffers then protected by an uninitialized or destroyed mutex. Fix this by introducing a "active" flag which is set during probe, and only invalidate buffers which where flaged as "active". Tested on a Dell Inspiron 3505. Fixes: 3b7eeff93d29 ("platform/x86: dell-ddv: Add hwmon support") Signed-off-by: Armin Wolf <W_Armin@gmx.de> Link: https://lore.kernel.org/r/20230218115318.20662-1-W_Armin@gmx.de Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/platform/x86/dell/dell-wmi-ddv.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/platform/x86/dell/dell-wmi-ddv.c b/drivers/platform/x86/dell/dell-wmi-ddv.c
index d547c9d09725..eff4e9649faf 100644
--- a/drivers/platform/x86/dell/dell-wmi-ddv.c
+++ b/drivers/platform/x86/dell/dell-wmi-ddv.c
@@ -96,6 +96,7 @@ struct combined_chip_info {
};
struct dell_wmi_ddv_sensors {
+ bool active;
struct mutex lock; /* protect caching */
unsigned long timestamp;
union acpi_object *obj;
@@ -520,6 +521,9 @@ static struct hwmon_channel_info *dell_wmi_ddv_channel_create(struct device *dev
static void dell_wmi_ddv_hwmon_cache_invalidate(struct dell_wmi_ddv_sensors *sensors)
{
+ if (!sensors->active)
+ return;
+
mutex_lock(&sensors->lock);
kfree(sensors->obj);
sensors->obj = NULL;
@@ -530,6 +534,7 @@ static void dell_wmi_ddv_hwmon_cache_destroy(void *data)
{
struct dell_wmi_ddv_sensors *sensors = data;
+ sensors->active = false;
mutex_destroy(&sensors->lock);
kfree(sensors->obj);
}
@@ -549,6 +554,7 @@ static struct hwmon_channel_info *dell_wmi_ddv_channel_init(struct wmi_device *w
return ERR_PTR(ret);
mutex_init(&sensors->lock);
+ sensors->active = true;
ret = devm_add_action_or_reset(&wdev->dev, dell_wmi_ddv_hwmon_cache_destroy, sensors);
if (ret < 0)
@@ -852,7 +858,7 @@ static int dell_wmi_ddv_resume(struct device *dev)
{
struct dell_wmi_ddv_data *data = dev_get_drvdata(dev);
- /* Force re-reading of all sensors */
+ /* Force re-reading of all active sensors */
dell_wmi_ddv_hwmon_cache_invalidate(&data->fans);
dell_wmi_ddv_hwmon_cache_invalidate(&data->temps);