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Date:   Wed, 6 Apr 2022 10:21:45 +0200
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Jaewon Kim <jaewon02.kim@samsung.com>
Cc:     Krzysztof Kozlowski <krzk@kernel.org>,
        Alim Akhtar <alim.akhtar@samsung.com>,
        Jiri Slaby <jirislaby@kernel.org>,
        linux-samsung-soc@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-serial@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Chanho Park <chanho61.park@samsung.com>
Subject: Re: [PATCH 1/1] tty: serial: samsung: add spin_lock for interrupt
 and console_write
Message-ID: <Yk1NmTdUgMcSIq1O@kroah.com>
References: <20220406082216.11206-1-jaewon02.kim@samsung.com>
 <CGME20220406081823epcas2p2f7afa27e2402c4fc02c9bee5972bed4f@epcas2p2.samsung.com>
 <20220406082216.11206-2-jaewon02.kim@samsung.com>
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In-Reply-To: <20220406082216.11206-2-jaewon02.kim@samsung.com>
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On Wed, Apr 06, 2022 at 05:22:16PM +0900, Jaewon Kim wrote:
> The console_write and IRQ handler can run concurrently.
> Problems may occurs console_write is continuously executed while
> the IRQ handler is running.
> 
> Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
> ---
>  drivers/tty/serial/samsung_tty.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
> index e1585fbae909..9db479d728b5 100644
> --- a/drivers/tty/serial/samsung_tty.c
> +++ b/drivers/tty/serial/samsung_tty.c
> @@ -2480,12 +2480,24 @@ s3c24xx_serial_console_write(struct console *co, const char *s,
>  			     unsigned int count)
>  {
>  	unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
> +	unsigned long flags;
> +	bool locked = 1;

"1" is not a boolean :)