Re: [pdx86-platform-drivers-x86:for-next 31/36] drivers/platform/x86/thinkpad_acpi.c:11154 thinkpad_acpi_module_exit() error: don't call input_free_device() after input_unregister_device()

[Hans de Goede]

Hi Dan,

On 11/30/21 09:05, Dan Carpenter wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git for-next
> head:   e9ff190973df2c417c2a97a8b70e709e0bdc2716
> commit: 67e7d50d13e94abeaf82e9945dce929352771b94 [31/36] platform/x86: thinkpad_acpi: Move input_unregister_device() to the top of thinkpad_acpi_module_exit()
> config: i386-randconfig-m021-20211129 (https://download.01.org/0day-ci/archive/20211129/202111292341.pt8nIc7T-lkp@xxxxxxxxx/config)
> compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> 
> New smatch warnings:
> drivers/platform/x86/thinkpad_acpi.c:11154 thinkpad_acpi_module_exit() error: don't call input_free_device() after input_unregister_device()
> 
> vim +11154 drivers/platform/x86/thinkpad_acpi.c
> 
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11130  static void thinkpad_acpi_module_exit(void)
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11131  {
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11132  	struct ibm_struct *ibm, *itmp;
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11133  
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11134  	tpacpi_lifecycle = TPACPI_LIFE_EXITING;
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11135  
> 67e7d50d13e94ab drivers/platform/x86/thinkpad_acpi.c Hans de Goede               2021-11-23  11136  	if (tp_features.input_device_registered)
> 67e7d50d13e94ab drivers/platform/x86/thinkpad_acpi.c Hans de Goede               2021-11-23  11137  		input_unregister_device(tpacpi_inputdev);
>                                                                                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> 
> 526ac103dbc6729 drivers/platform/x86/thinkpad_acpi.c Hans de Goede               2021-11-23  11138  	if (tpacpi_hwmon)
> 526ac103dbc6729 drivers/platform/x86/thinkpad_acpi.c Hans de Goede               2021-11-23  11139  		hwmon_device_unregister(tpacpi_hwmon);
> 2f5ad08f3eec8d4 drivers/platform/x86/thinkpad_acpi.c Hans de Goede               2021-11-23  11140  	if (tp_features.sensors_pdrv_registered)
> 2f5ad08f3eec8d4 drivers/platform/x86/thinkpad_acpi.c Hans de Goede               2021-11-23  11141  		platform_driver_unregister(&tpacpi_hwmon_pdriver);
> 2f5ad08f3eec8d4 drivers/platform/x86/thinkpad_acpi.c Hans de Goede               2021-11-23  11142  	if (tp_features.platform_drv_registered)
> 2f5ad08f3eec8d4 drivers/platform/x86/thinkpad_acpi.c Hans de Goede               2021-11-23  11143  		platform_driver_unregister(&tpacpi_pdriver);
> 2f5ad08f3eec8d4 drivers/platform/x86/thinkpad_acpi.c Hans de Goede               2021-11-23  11144  
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11145  	list_for_each_entry_safe_reverse(ibm, itmp,
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11146  					 &tpacpi_all_drivers,
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11147  					 all_drivers) {
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11148  		ibm_exit(ibm);
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11149  	}
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11150  
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11151  	dbg_printk(TPACPI_DBG_INIT, "finished subdriver exit path...\n");
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08  11152  
> 67e7d50d13e94ab drivers/platform/x86/thinkpad_acpi.c Hans de Goede               2021-11-23  11153  	if (tpacpi_inputdev)
> b21a15f6d065e83 drivers/misc/thinkpad_acpi.c         Henrique de Moraes Holschuh 2008-01-08 @11154  		input_free_device(tpacpi_inputdev);
>                                                                                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> I haven't seen this warning in a long time, so I forget why it exists.
> But apparently it's against the rules.  :P

Yes, this is my bad. I've dropped this cleanup patch from the pdx86 for-next branch now,
since clearly this is a bad idea.

Thank you for catching this.

Regards,

Hans