Date:   Mon, 6 Feb 2023 07:48:03 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Hillf Danton <hdanton@sina.com>
Cc:     Alan Stern <stern@rowland.harvard.edu>,
        Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        "Rafael J. Wysocki" <rafael@kernel.org>, linux-mm@kvack.org,
        LKML <linux-kernel@vger.kernel.org>,
        USB list <linux-usb@vger.kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: Converting dev->mutex into dev->spinlock ?
Message-ID: <Y+Cio48RvJe9Y2cv@kroah.com>
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On Mon, Feb 06, 2023 at 02:43:05PM +0800, Hillf Danton wrote:
> On Mon, 6 Feb 2023 06:17:03 +0100 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > On Mon, Feb 06, 2023 at 10:56:29AM +0800, Hillf Danton wrote:
> > > On Sun, 5 Feb 2023 11:46:06 -0500 Alan Stern <stern@rowland.harvard.edu>
> > > > 
> > > > And by the way, by disabling lockdep validation I am declaraing that 
> > > > enabling it would cause an overwhelming number of false positives, 
> > > 
> > > Could you share 5 false positives you see upstream to help understand how
> > > it is useless?
> > 
> > Please see this other email in this thread:
> > 	https://lore.kernel.org/r/Y98FLlr7jkiFlV0k@rowland.harvard.edu
> 
> What lockdep warnings?  Specific examples, please.

Remove the one line of code, as per the patch in this thread, and boot
with lockdep enabled and see what happens if you wish to see them
yourself.

thanks,

greg k-h