iwlwifi: mvm: avoid panics with thermal device usage
Thermal zone device registration can fail, and in this case
we don't want to remove WiFi functionality. This is why the
thermal zone registration function is void, and the flows
continue even if the thermal zone device registration failed.
Same applies for the cooling device.
This means that we at least need to remember that the thermal
zone device didn't register properly and take the minimal
precautions to avoid panic'ing when we access it.
This was missing.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/tt.c b/drivers/net/wireless/intel/iwlwifi/mvm/tt.c
index 999bcb8..0a02e98 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/tt.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/tt.c
@@ -211,10 +211,14 @@
* the firmware and hence to take the mutex.
* Avoid the deadlock by unlocking the mutex here.
*/
- mutex_unlock(&mvm->mutex);
- thermal_notify_framework(mvm->tz_device.tzone,
- mvm->tz_device.fw_trips_index[ths_crossed]);
- mutex_lock(&mvm->mutex);
+ if (mvm->tz_device.tzone) {
+ struct iwl_mvm_thermal_device *tz_dev = &mvm->tz_device;
+
+ mutex_unlock(&mvm->mutex);
+ thermal_notify_framework(tz_dev->tzone,
+ tz_dev->fw_trips_index[ths_crossed]);
+ mutex_lock(&mvm->mutex);
+ }
#endif /* CONFIG_THERMAL */
}
@@ -520,16 +524,20 @@
lockdep_assert_held(&mvm->mutex);
+ if (!mvm->tz_device.tzone)
+ return -EINVAL;
+
/* The driver holds array of temperature trips that are unsorted
* and uncompressed, the FW should get it compressed and sorted
*/
/* compress temp_trips to cmd array, remove uninitialized values*/
- for (i = 0; i < IWL_MAX_DTS_TRIPS; i++)
+ for (i = 0; i < IWL_MAX_DTS_TRIPS; i++) {
if (mvm->tz_device.temp_trips[i] != S16_MIN) {
cmd.thresholds[idx++] =
cpu_to_le16(mvm->tz_device.temp_trips[i]);
}
+ }
cmd.num_temps = cpu_to_le32(idx);
if (!idx)
@@ -696,6 +704,7 @@
IWL_DEBUG_TEMP(mvm,
"Failed to register to thermal zone (err = %ld)\n",
PTR_ERR(mvm->tz_device.tzone));
+ mvm->tz_device.tzone = NULL;
return;
}
@@ -750,6 +759,10 @@
return ret;
}
+ /* can happen if the registration failed */
+ if (!mvm->cooling_dev.cdev)
+ return -EINVAL;
+
if (op == CTDP_CMD_OPERATION_START)
mvm->cooling_dev.cur_state = budget;
@@ -812,15 +825,12 @@
.set_cur_state = iwl_mvm_tcool_set_cur_state,
};
-int iwl_mvm_cooling_device_register(struct iwl_mvm *mvm)
+static void iwl_mvm_cooling_device_register(struct iwl_mvm *mvm)
{
char name[] = "iwlwifi";
- if (!iwl_mvm_is_ctdp_supported(mvm)) {
- mvm->cooling_dev.cdev = NULL;
-
- return 0;
- }
+ if (!iwl_mvm_is_ctdp_supported(mvm))
+ return;
BUILD_BUG_ON(ARRAY_SIZE(name) >= THERMAL_NAME_LENGTH);
@@ -833,34 +843,29 @@
IWL_DEBUG_TEMP(mvm,
"Failed to register to cooling device (err = %ld)\n",
PTR_ERR(mvm->cooling_dev.cdev));
- return PTR_ERR(mvm->cooling_dev.cdev);
+ mvm->cooling_dev.cdev = NULL;
+ return;
}
-
- return 0;
}
static void iwl_mvm_thermal_zone_unregister(struct iwl_mvm *mvm)
{
- if (!iwl_mvm_is_tt_in_fw(mvm))
+ if (!iwl_mvm_is_tt_in_fw(mvm) || !mvm->tz_device.tzone)
return;
- if (mvm->tz_device.tzone) {
- IWL_DEBUG_TEMP(mvm, "Thermal zone device unregister\n");
- thermal_zone_device_unregister(mvm->tz_device.tzone);
- mvm->tz_device.tzone = NULL;
- }
+ IWL_DEBUG_TEMP(mvm, "Thermal zone device unregister\n");
+ thermal_zone_device_unregister(mvm->tz_device.tzone);
+ mvm->tz_device.tzone = NULL;
}
static void iwl_mvm_cooling_device_unregister(struct iwl_mvm *mvm)
{
- if (!iwl_mvm_is_ctdp_supported(mvm))
+ if (!iwl_mvm_is_ctdp_supported(mvm) || !mvm->cooling_dev.cdev)
return;
- if (mvm->cooling_dev.cdev) {
- IWL_DEBUG_TEMP(mvm, "Cooling device unregister\n");
- thermal_cooling_device_unregister(mvm->cooling_dev.cdev);
- mvm->cooling_dev.cdev = NULL;
- }
+ IWL_DEBUG_TEMP(mvm, "Cooling device unregister\n");
+ thermal_cooling_device_unregister(mvm->cooling_dev.cdev);
+ mvm->cooling_dev.cdev = NULL;
}
#endif /* CONFIG_THERMAL */