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Dmitry Torokhov
35f0a0dced
When a device is opened via input_open_device(), the driver's open() callback is invoked. Some drivers, like cm109, submit URBs or perform other hardware initialization in their open() callbacks. However, the input core does not prevent dev->event() from being called concurrently during the driver's open() execution. For instance, if a console beep occurs, the kbd handler might inject an EV_SND event. This can lead to double list_add BUGs if the driver submits the same URB in both open() and event() paths without adequate synchronization. To fix this, introduce a ready flag in the input_dev structure. For complex devices (where dev->open is defined), this flag is set to true only after the driver's open() method successfully completes. The core now checks ready in input_event_dispose() and input_dev_toggle() to prevent events from reaching the hardware before it is fully prepared. For simple devices (no open callback), events are delivered immediately. We also replay the logical state in input_open_device() by calling input_dev_toggle() right after marking the device ready, ensuring no events are permanently lost. In the inhibit path, we ensure that physical feedback (LEDs/sounds) is turned off before the device is closed, and we synchronize the inhibited state transition under the event lock to prevent races with incoming events. Assisted-by: Antigravity:gemini-3.5-flash Link: https://patch.msgid.link/20260803005210.1251102-1-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>