Commits
Johan Hovold committed cb25505fc60
USB: cdc-acm: fix device unregistration Unregister tty device in disconnect as is required by the USB stack. By deferring unregistration to when the last tty reference is dropped, the parent interface device can get unregistered before the child resulting in broken hotplug events being generated when the tty is finally closed: KERNEL[2290.798128] remove /devices/pci0000:00/0000:00:1d.7/usb2/2-1/2-1:3.1 (usb) KERNEL[2290.804589] remove /devices/pci0000:00/0000:00:1d.7/usb2/2-1 (usb) KERNEL[2294.554799] remove /2-1:3.1/tty/ttyACM0 (tty) The driver must deal with tty callbacks after disconnect by checking the disconnected flag. Specifically, further opens must be prevented and this is already implemented. Cc: stable <stable@vger.kernel.org> Cc: Oliver Neukum <oneukum@suse.de> Acked-by: Oliver Neukum <oneukum@suse.de> Signed-off-by: Johan Hovold <jhovold@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>