From: Yuan Can <yuancan@xxxxxxxxxx> [ Upstream commit 5a2d96623670155d94aca72c320c0ac27bdc6bd2 ] The following WARNING message was given when rmmod cros_usbpd_notify: Unexpected driver unregister! WARNING: CPU: 0 PID: 253 at drivers/base/driver.c:270 driver_unregister+0x8a/0xb0 Modules linked in: cros_usbpd_notify(-) CPU: 0 PID: 253 Comm: rmmod Not tainted 6.1.0-rc3 #24 ... Call Trace: <TASK> cros_usbpd_notify_exit+0x11/0x1e [cros_usbpd_notify] __x64_sys_delete_module+0x3c7/0x570 ? __ia32_sys_delete_module+0x570/0x570 ? lock_is_held_type+0xe3/0x140 ? syscall_enter_from_user_mode+0x17/0x50 ? rcu_read_lock_sched_held+0xa0/0xd0 ? syscall_enter_from_user_mode+0x1c/0x50 do_syscall_64+0x37/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f333fe9b1b7 The reason is that the cros_usbpd_notify_init() does not check the return value of platform_driver_register(), and the cros_usbpd_notify can install successfully even if platform_driver_register() failed. Fix by checking the return value of platform_driver_register() and unregister cros_usbpd_notify_plat_driver when it failed. Fixes: ec2daf6e33f9 ("platform: chrome: Add cros-usbpd-notify driver") Signed-off-by: Yuan Can <yuancan@xxxxxxxxxx> Reviewed-by: Brian Norris <briannorris@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20221117080823.77549-1-yuancan@xxxxxxxxxx Signed-off-by: Prashant Malani <pmalani@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/platform/chrome/cros_usbpd_notify.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/platform/chrome/cros_usbpd_notify.c b/drivers/platform/chrome/cros_usbpd_notify.c index 7f36142ab12a..19390147ac9d 100644 --- a/drivers/platform/chrome/cros_usbpd_notify.c +++ b/drivers/platform/chrome/cros_usbpd_notify.c @@ -284,7 +284,11 @@ static int __init cros_usbpd_notify_init(void) return ret; #ifdef CONFIG_ACPI - platform_driver_register(&cros_usbpd_notify_acpi_driver); + ret = platform_driver_register(&cros_usbpd_notify_acpi_driver); + if (ret) { + platform_driver_unregister(&cros_usbpd_notify_plat_driver); + return ret; + } #endif return 0; } -- 2.35.1