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SubjectRacy kb->ledflagstate and kb->default_ledflagstate
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Hi,

We observed a race over kb->ledflagstate and kb->default_ledflagstate
when two threads are running vt_do_kdskled() in parallel:

Thread-1 Thread-2
// holding led_lock // holding kbd_event_lock
kb->ledflagstate = (arg & 7);
ucval = kb->ledflagstate |
(kb->default_ledflagstate << 4);
kb->default_ledflagstate = ((arg >> 4) & 7);

Is it better to hold both led_lock and kbd_event_lock under case KDGKBLED?
We are happy to submit the patch if it makes sense.

Thanks

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