tree: https://github.com/thierryreding/linux for-5.13/work head: 009ea3ee74a12859073a37d2ef800fa154ff7705 commit: 21e83ea5975c6e323f7b720ced5b045a91d6e808 [2/49] gpu: host1x: Use different lock classes for each client config: arm-defconfig (attached as .config) compiler: arm-linux-gnueabi-gcc (GCC) 9.3.0 reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/thierryreding/linux/commit/21e83ea5975c6e323f7b720ced5... git remote add thierryreding https://github.com/thierryreding/linux git fetch --no-tags thierryreding for-5.13/work git checkout 21e83ea5975c6e323f7b720ced5b045a91d6e808 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): drivers/gpu/host1x/bus.c:720: warning: Function parameter or member 'key' not described in '__host1x_client_register' vim +720 drivers/gpu/host1x/bus.c 776dc38403676f Thierry Reding 2013-10-14 706 466749f13e33d8 Thierry Reding 2017-04-10 707 /** 466749f13e33d8 Thierry Reding 2017-04-10 708 * host1x_client_register() - register a host1x client 466749f13e33d8 Thierry Reding 2017-04-10 709 * @client: host1x client 466749f13e33d8 Thierry Reding 2017-04-10 710 * 466749f13e33d8 Thierry Reding 2017-04-10 711 * Registers a host1x client with each host1x controller instance. Note that 466749f13e33d8 Thierry Reding 2017-04-10 712 * each client will only match their parent host1x controller and will only be 466749f13e33d8 Thierry Reding 2017-04-10 713 * associated with that instance. Once all clients have been registered with 466749f13e33d8 Thierry Reding 2017-04-10 714 * their parent host1x controller, the infrastructure will set up the logical 466749f13e33d8 Thierry Reding 2017-04-10 715 * device and call host1x_device_init(), which will in turn call each client's 466749f13e33d8 Thierry Reding 2017-04-10 716 * &host1x_client_ops.init implementation. 466749f13e33d8 Thierry Reding 2017-04-10 717 */ 21e83ea5975c6e Mikko Perttunen 2021-01-11 718 int __host1x_client_register(struct host1x_client *client, 21e83ea5975c6e Mikko Perttunen 2021-01-11 719 struct lock_class_key *key) 776dc38403676f Thierry Reding 2013-10-14 @720 { 776dc38403676f Thierry Reding 2013-10-14 721 struct host1x *host1x; 776dc38403676f Thierry Reding 2013-10-14 722 int err; 776dc38403676f Thierry Reding 2013-10-14 723 fd67e9c6ed5af2 Thierry Reding 2019-12-02 724 INIT_LIST_HEAD(&client->list); 21e83ea5975c6e Mikko Perttunen 2021-01-11 725 __mutex_init(&client->lock, "host1x client lock", key); fd67e9c6ed5af2 Thierry Reding 2019-12-02 726 client->usecount = 0; fd67e9c6ed5af2 Thierry Reding 2019-12-02 727 776dc38403676f Thierry Reding 2013-10-14 728 mutex_lock(&devices_lock); 776dc38403676f Thierry Reding 2013-10-14 729 776dc38403676f Thierry Reding 2013-10-14 730 list_for_each_entry(host1x, &devices, list) { 0c7dfd36b73be6 Thierry Reding 2014-05-22 731 err = host1x_add_client(host1x, client); 776dc38403676f Thierry Reding 2013-10-14 732 if (!err) { 776dc38403676f Thierry Reding 2013-10-14 733 mutex_unlock(&devices_lock); 776dc38403676f Thierry Reding 2013-10-14 734 return 0; 776dc38403676f Thierry Reding 2013-10-14 735 } 776dc38403676f Thierry Reding 2013-10-14 736 } 776dc38403676f Thierry Reding 2013-10-14 737 776dc38403676f Thierry Reding 2013-10-14 738 mutex_unlock(&devices_lock); 776dc38403676f Thierry Reding 2013-10-14 739 776dc38403676f Thierry Reding 2013-10-14 740 mutex_lock(&clients_lock); 776dc38403676f Thierry Reding 2013-10-14 741 list_add_tail(&client->list, &clients); 776dc38403676f Thierry Reding 2013-10-14 742 mutex_unlock(&clients_lock); 776dc38403676f Thierry Reding 2013-10-14 743 776dc38403676f Thierry Reding 2013-10-14 744 return 0; 776dc38403676f Thierry Reding 2013-10-14 745 } 21e83ea5975c6e Mikko Perttunen 2021-01-11 746 EXPORT_SYMBOL(__host1x_client_register); 776dc38403676f Thierry Reding 2013-10-14 747 :::::: The code at line 720 was first introduced by commit :::::: 776dc38403676f499a73d32e2e7c61eb5b42f736 drm/tegra: Move subdevice infrastructure to host1x :::::: TO: Thierry Reding <treding(a)nvidia.com&gt; :::::: CC: Thierry Reding <treding(a)nvidia.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org