6.15-stable review patch. If anyone has any objections, please let me know.
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From: Benjamin Berg benjamin.berg@intel.com
[ Upstream commit 83128399f3b4926ab73ce8e5081ce6595e9230e9 ]
The driver must not hold the wiphy mutex when unregistering the thermal devices. Do not hold the lock for the call to iwl_mld_thermal_exit and only do a lock/unlock to cancel the ct_kill_exit_wk work.
The problem is that iwl_mld_tzone_get_temp needs to take the wiphy lock while the thermal code is holding its own locks already. When unregistering the device, the reverse would happen as the driver was calling thermal_cooling_device_unregister with the wiphy mutex already held.
It is not likely to trigger this deadlock as it can only happen if the thermal code is polling the temperature while the driver is being unloaded. However, lockdep reported it so fix it.
Signed-off-by: Benjamin Berg benjamin.berg@intel.com Reviewed-by: Johannes Berg johannes.berg@intel.com Link: https://patch.msgid.link/20250506194102.3407967-12-miriam.rachel.korenblit@i... Signed-off-by: Miri Korenblit miriam.rachel.korenblit@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/intel/iwlwifi/mld/mld.c | 3 ++- drivers/net/wireless/intel/iwlwifi/mld/thermal.c | 4 ++++ 2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/intel/iwlwifi/mld/mld.c b/drivers/net/wireless/intel/iwlwifi/mld/mld.c index 7a098942dc802..21f65442638dd 100644 --- a/drivers/net/wireless/intel/iwlwifi/mld/mld.c +++ b/drivers/net/wireless/intel/iwlwifi/mld/mld.c @@ -475,8 +475,9 @@ iwl_op_mode_mld_stop(struct iwl_op_mode *op_mode) iwl_mld_ptp_remove(mld); iwl_mld_leds_exit(mld);
- wiphy_lock(mld->wiphy); iwl_mld_thermal_exit(mld); + + wiphy_lock(mld->wiphy); iwl_mld_low_latency_stop(mld); iwl_mld_deinit_time_sync(mld); wiphy_unlock(mld->wiphy); diff --git a/drivers/net/wireless/intel/iwlwifi/mld/thermal.c b/drivers/net/wireless/intel/iwlwifi/mld/thermal.c index 1909953a9be98..670ac43528006 100644 --- a/drivers/net/wireless/intel/iwlwifi/mld/thermal.c +++ b/drivers/net/wireless/intel/iwlwifi/mld/thermal.c @@ -419,6 +419,8 @@ static void iwl_mld_cooling_device_unregister(struct iwl_mld *mld)
void iwl_mld_thermal_initialize(struct iwl_mld *mld) { + lockdep_assert_not_held(&mld->wiphy->mtx); + wiphy_delayed_work_init(&mld->ct_kill_exit_wk, iwl_mld_exit_ctkill);
#ifdef CONFIG_THERMAL @@ -429,7 +431,9 @@ void iwl_mld_thermal_initialize(struct iwl_mld *mld)
void iwl_mld_thermal_exit(struct iwl_mld *mld) { + wiphy_lock(mld->wiphy); wiphy_delayed_work_cancel(mld->wiphy, &mld->ct_kill_exit_wk); + wiphy_unlock(mld->wiphy);
#ifdef CONFIG_THERMAL iwl_mld_cooling_device_unregister(mld);