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Date:   Mon, 14 Aug 2023 12:21:23 +0200
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To:     Petr Mladek <pmladek@suse.com>,
        John Ogness <john.ogness@linutronix.de>
Cc:     gregkh@linuxfoundation.org, linux-serial@vger.kernel.org,
        linux-kernel@vger.kernel.org, Vlastimil Babka <vbabka@suse.cz>,
        Thomas Gleixner <tglx@linutronix.de>
References: <20230811064340.13400-1-jirislaby@kernel.org>
 <878rae175n.fsf@jogness.linutronix.de>
 <7d8ae4f8-8900-5a06-5b7b-d4a3aea0673e@kernel.org>
 <87bkfa6nvx.fsf@jogness.linutronix.de> <ZNn7KHY3iMRarqAZ@alley>
From:   Jiri Slaby <jirislaby@kernel.org>
Subject: Re: [PATCH] serial: 8250: drop lockdep annotation from
 serial8250_clear_IER()
In-Reply-To: <ZNn7KHY3iMRarqAZ@alley>
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On 14. 08. 23, 12:00, Petr Mladek wrote:
> I personally vote to keep it as is unless people see this warning
> on daily basis. After all, the lockdep splat is correct. The serial
> console might not work correctly in panic() when there is the race.

Sorry, but no, the warning is not correct at all. The code path 
deliberately does NOT take the lock and calls a function which is 
currently annotated that the lock is _always_ taken. Therefore, the 
warning is clearly a false positive and I see no reason in keeping it.

Hopefully this is fixed as John described earlier. Until then, I see no 
point bothering people with false alarms.

thanks,
-- 
js
suse labs