Date:   Sat, 11 Mar 2023 19:18:00 +0000
From:   Jonathan Cameron <jic23@kernel.org>
To:     James Clark <james.clark@arm.com>
Cc:     linux-kernel@vger.kernel.org, linux@roeck-us.net,
        michal.simek@amd.com, Jonathan Corbet <corbet@lwn.net>,
        Jean Delvare <jdelvare@suse.com>,
        Anand Ashok Dumbre <anand.ashok.dumbre@xilinx.com>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Michal Simek <michal.simek@xilinx.com>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>, linux-doc@vger.kernel.org,
        linux-hwmon@vger.kernel.org, linux-iio@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-arm-msm@vger.kernel.org, linux-serial@vger.kernel.org
Subject: Re: [PATCH v2 4/4] serial: qcom_geni: Use devm_krealloc_array
Message-ID: <20230311191800.74ec2b84@jic23-huawei>
In-Reply-To: <20230309150334.216760-5-james.clark@arm.com>
References: <20230309150334.216760-1-james.clark@arm.com>
        <20230309150334.216760-5-james.clark@arm.com>
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On Thu,  9 Mar 2023 15:03:33 +0000
James Clark <james.clark@arm.com> wrote:

> Now that it exists, use it instead of doing the multiplication manually.
> 
> Signed-off-by: James Clark <james.clark@arm.com>

Hmm. I've stared at the users of this for a bit, and it's not actually obvious
that it's being used as an array of u32.  The only typed user of this is as
the 2nd parameter of  
tty_insert_flip_string() which is an unsigned char *

I wonder if that sizeof(u32) isn't a 'correct' description of where the 4 is coming
from even if it has the right value?  Perhaps the fifo depth is just a multiple of 4?

Jonathan


> ---
>  drivers/tty/serial/qcom_geni_serial.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
> index d69592e5e2ec..23fc33d182ac 100644
> --- a/drivers/tty/serial/qcom_geni_serial.c
> +++ b/drivers/tty/serial/qcom_geni_serial.c
> @@ -1056,9 +1056,9 @@ static int setup_fifos(struct qcom_geni_serial_port *port)
>  		(port->tx_fifo_depth * port->tx_fifo_width) / BITS_PER_BYTE;
>  
>  	if (port->rx_buf && (old_rx_fifo_depth != port->rx_fifo_depth) && port->rx_fifo_depth) {
> -		port->rx_buf = devm_krealloc(uport->dev, port->rx_buf,
> -					     port->rx_fifo_depth * sizeof(u32),
> -					     GFP_KERNEL);
> +		port->rx_buf = devm_krealloc_array(uport->dev, port->rx_buf,
> +						   port->rx_fifo_depth, sizeof(u32),
> +						   GFP_KERNEL);
>  		if (!port->rx_buf)
>  			return -ENOMEM;
>  	}