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Date:   Thu, 10 Nov 2022 15:13:56 +0000
From:   Daniel Thompson <daniel.thompson@linaro.org>
To:     John Ogness <john.ogness@linutronix.de>
Cc:     Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel@vger.kernel.org,
        Jason Wessel <jason.wessel@windriver.com>,
        Douglas Anderson <dianders@chromium.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>,
        kgdb-bugreport@lists.sourceforge.net, linux-serial@vger.kernel.org
Subject: Re: [PATCH printk v3 37/40] tty: serial: kgdboc: synchronize
 tty_find_polling_driver() and register_console()
Message-ID: <Y20VNMu1VCW2qP13@frostfish>
References: <20221107141638.3790965-1-john.ogness@linutronix.de>
 <20221107141638.3790965-38-john.ogness@linutronix.de>
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In-Reply-To: <20221107141638.3790965-38-john.ogness@linutronix.de>
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On Mon, Nov 07, 2022 at 03:22:35PM +0106, John Ogness wrote:
> Calling tty_find_polling_driver() can lead to uart_set_options() being
> called (via the poll_init() callback of tty_operations) to configure the
> uart. But uart_set_options() can also be called by register_console()
> (via the setup() callback of console).
>
> Take the console_list_lock to synchronize against register_console() and
> also use it for console list traversal. This also ensures the console list
> cannot change until the polling console has been chosen.
>
> Signed-off-by: John Ogness <john.ogness@linutronix.de>

Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>


Daniel.