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Subject: Re: BUG: MAX_LOCKDEP_KEYS too low!
To:     Alexey Kardashevskiy <aik@ozlabs.ru>
Cc:     Dmitry Vyukov <dvyukov@google.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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From:   Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
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Date:   Sat, 23 Jan 2021 22:12:50 +0900
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On 2021/01/23 20:26, Alexey Kardashevskiy wrote:
> Should not the first 8192 from "grep lock-classes /proc/lockdep_stats" decrease
> after time (it does not), or once it has failed, it is permanent?

Since lockdep_unregister_key() becomes a no-op because graph_lock() returns 0
due to debug_locks being changed from 1 to 0 by __debug_locks_off() from
debug_locks_off() from debug_locks_off_graph_unlock(), lock-classes value in
/proc/lockdep_stats will not decrease after "BUG: MAX_LOCKDEP_KEYS too low!"
is printed.