Date:   Mon, 13 Feb 2023 10:28:08 -0500
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Kent Overstreet <kent.overstreet@linux.dev>,
        Kent Overstreet <kent.overstreet@gmail.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Coly Li <colyli@suse.de>,
        Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        syzkaller <syzkaller@googlegroups.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        USB list <linux-usb@vger.kernel.org>,
        Hillf Danton <hdanton@sina.com>
Subject: Re: [PATCH RFC] drivers/core: Replace lockdep_set_novalidate_class()
 with unique class keys
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On Mon, Feb 13, 2023 at 10:27:18AM +0100, Peter Zijlstra wrote:
> On Sun, Feb 12, 2023 at 03:19:16PM -0500, Alan Stern wrote:
> 
> > (Device names are often set after the device is initialized.  Does 
> > lockdep mind if a lock_class_key's name is changed after it has been 
> > registered?)
> 
> It does, althought I don't at the moment recall how hard it would be to
> change that.

If the names are only used for printing purposes, or other similarly 
innocuous things, it ought to be enough to set the name with 
smp_store_release() and read the name with smp_load_acquire().

Alan Stern