Re: [PATCH] serial: samsung: Checks the return value of function

From: Greg KH
Date: Mon Jan 04 2021 - 05:03:06 EST


On Mon, Jan 04, 2021 at 02:05:51PM +0530, Tamseel Shams wrote:
> "uart_add_one_port" function call may fail and return
> some error code, so adding a check for return value.
> If it is returning some error code, then displaying the
> result and returning back from there.
>
> Signed-off-by: Tamseel Shams <m.shams@xxxxxxxxxxx>
> ---
> drivers/tty/serial/samsung_tty.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
> index 6ef614d8648c..a220ba166ffe 100644
> --- a/drivers/tty/serial/samsung_tty.c
> +++ b/drivers/tty/serial/samsung_tty.c
> @@ -2072,7 +2072,11 @@ static int s3c24xx_serial_probe(struct platform_device *pdev)
> }
>
> dev_dbg(&pdev->dev, "%s: adding port\n", __func__);
> - uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
> + ret = uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "Failed to add uart port, err %d\n", ret);
> + return ret;

Why are you not unwinding the other logic that happened above? If this
fails, you need to properly do that as well, otherwise the driver is
still registered, right?

thanks,

greg k-h