Subject: [PATCH AUTOSEL 5.5 516/542] iwlwifi: mvm: Fix thermal zone registration

From: Sasha Levin <[email-masked]>
Date: Fri, 14 Feb 2020 10:48:28 -0500

From: Andrei Otcheretianski <[email-masked]>

[ Upstream commit baa6cf8450b72dcab11f37c47efce7c5b9b8ad0f ]

Use a unique name when registering a thermal zone. Otherwise, with
multiple NICS, we hit the following warning during the unregistration.

WARNING: CPU: 2 PID: 3525 at fs/sysfs/group.c:255
 RIP: 0010:sysfs_remove_group+0x80/0x90
 Call Trace:
  dpm_sysfs_remove+0x57/0x60
  device_del+0x5a/0x350
  ? sscanf+0x4e/0x70
  device_unregister+0x1a/0x60
  hwmon_device_unregister+0x4a/0xa0
  thermal_remove_hwmon_sysfs+0x175/0x1d0
  thermal_zone_device_unregister+0x188/0x1e0
  iwl_mvm_thermal_exit+0xe7/0x100 [iwlmvm]
  iwl_op_mode_mvm_stop+0x27/0x180 [iwlmvm]
  _iwl_op_mode_stop.isra.3+0x2b/0x50 [iwlwifi]
  iwl_opmode_deregister+0x90/0xa0 [iwlwifi]
  __exit_compat+0x10/0x2c7 [iwlmvm]
  __x64_sys_delete_module+0x13f/0x270
  do_syscall_64+0x5a/0x110
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Andrei Otcheretianski <[email-masked]>
Signed-off-by: Luca Coelho <[email-masked]>
Signed-off-by: Kalle Valo <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/net/wireless/intel/iwlwifi/mvm/tt.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/tt.c b/drivers/net/wireless/intel/iwlwifi/mvm/tt.c
index b5a16f00bada9..fcad25ffd811f 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/tt.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/tt.c
@@ -734,7 +734,8 @@ static  struct thermal_zone_device_ops tzone_ops = {
 static void iwl_mvm_thermal_zone_register(struct iwl_mvm *mvm)
 {
 	int i;
-	char name[] = "iwlwifi";
+	char name[16];
+	static atomic_t counter = ATOMIC_INIT(0);
 
 	if (!iwl_mvm_is_tt_in_fw(mvm)) {
 		mvm->tz_device.tzone = NULL;
@@ -744,6 +745,7 @@ static void iwl_mvm_thermal_zone_register(struct iwl_mvm *mvm)
 
 	BUILD_BUG_ON(ARRAY_SIZE(name) >= THERMAL_NAME_LENGTH);
 
+	sprintf(name, "iwlwifi_%u", atomic_inc_return(&counter) & 0xFF);
 	mvm->tz_device.tzone = thermal_zone_device_register(name,
 							IWL_MAX_DTS_TRIPS,
 							IWL_WRITABLE_TRIPS_MSK,
-- 
2.20.1