From: Jiri Kosina Date: Thu, 4 Sep 2014 06:56:06 +0000 (+0200) Subject: HID: thingm: fix workqueue race on remove X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=67a97845830f79584c9db8849ac723e5d2d57f65;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git HID: thingm: fix workqueue race on remove thingm_remove_rgb() needs to flush the workqueue after all the LED classes have been unregistered, otherwise the removal might race with another LED event coming, causing thingm_led_set() to schedule additional work after thingm_remove_rgb() has flushed it. This obviously causes oops later, as the scheduled work has been freed in the meantime. In addition to that, move the hid_hw_stop() to an earlier place, so that dmesg is not polluted by failure messages about not being able to write the LED while the device is being shut down. Reported-and-tested-by: Dylan Alex Simon Signed-off-by: Jiri Kosina --- diff --git a/drivers/hid/hid-thingm.c b/drivers/hid/hid-thingm.c index 134be89b15ea..f206398a5d54 100644 --- a/drivers/hid/hid-thingm.c +++ b/drivers/hid/hid-thingm.c @@ -208,10 +208,10 @@ unregister_red: static void thingm_remove_rgb(struct thingm_rgb *rgb) { - flush_work(&rgb->work); led_classdev_unregister(&rgb->red.ldev); led_classdev_unregister(&rgb->green.ldev); led_classdev_unregister(&rgb->blue.ldev); + flush_work(&rgb->work); } static int thingm_probe(struct hid_device *hdev, const struct hid_device_id *id) @@ -286,10 +286,10 @@ static void thingm_remove(struct hid_device *hdev) struct thingm_device *tdev = hid_get_drvdata(hdev); int i; + hid_hw_stop(hdev); + for (i = 0; i < tdev->fwinfo->numrgb; ++i) thingm_remove_rgb(tdev->rgb + i); - - hid_hw_stop(hdev); } static const struct hid_device_id thingm_table[] = {