Message-ID: <3a41a7ad-37c1-7104-79b2-b9be53790a6c@arm.com>
Date:   Thu, 9 Mar 2023 15:04:50 +0000
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From:   James Clark <james.clark@arm.com>
Subject: Re: [PATCH 3/4] iio: adc: Use devm_krealloc_array
To:     Michal Simek <michal.simek@amd.com>, linux-kernel@vger.kernel.org
Cc:     Jonathan Corbet <corbet@lwn.net>,
        Guenter Roeck <linux@roeck-us.net>,
        Jean Delvare <jdelvare@suse.com>,
        Anand Ashok Dumbre <anand.ashok.dumbre@xilinx.com>,
        Jonathan Cameron <jic23@kernel.org>,
        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
References: <20230306152723.3090195-1-james.clark@arm.com>
 <20230306152723.3090195-4-james.clark@arm.com>
 <a5bb0516-9a21-5d46-d557-f02893ac8bf4@amd.com>
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On 08/03/2023 11:58, Michal Simek wrote:
> 
> 
> On 3/6/23 16:27, James Clark wrote:
>>
>> Now that it exists, use it instead of doing the multiplication and
>> checking for overflow manually.
>>
>> Signed-off-by: James Clark <james.clark@arm.com>
>> ---
>>   drivers/iio/adc/xilinx-ams.c       |  9 +++------
>>   drivers/iio/adc/xilinx-xadc-core.c | 17 +++++++----------
>>   2 files changed, 10 insertions(+), 16 deletions(-)
>>
>> diff --git a/drivers/iio/adc/xilinx-ams.c b/drivers/iio/adc/xilinx-ams.c
>> index 34cf336b3490..f0b71a1220e0 100644
>> --- a/drivers/iio/adc/xilinx-ams.c
>> +++ b/drivers/iio/adc/xilinx-ams.c
>> @@ -1263,7 +1263,7 @@ static int ams_parse_firmware(struct iio_dev
>> *indio_dev)
>>          struct device *dev = indio_dev->dev.parent;
>>          struct fwnode_handle *child = NULL;
>>          struct fwnode_handle *fwnode = dev_fwnode(dev);
>> -       size_t ams_size, dev_size;
>> +       size_t ams_size;
>>          int ret, ch_cnt = 0, i, rising_off, falling_off;
>>          unsigned int num_channels = 0;
>>
>> @@ -1320,11 +1320,8 @@ static int ams_parse_firmware(struct iio_dev
>> *indio_dev)
>>                  }
>>          }
>>
>> -       dev_size = array_size(sizeof(*dev_channels), num_channels);
>> -       if (dev_size == SIZE_MAX)
>> -               return -ENOMEM;
>> -
>> -       dev_channels = devm_krealloc(dev, ams_channels, dev_size,
>> GFP_KERNEL);
>> +       dev_channels = devm_krealloc_array(dev, ams_channels,
>> num_channels,
>> +                                          sizeof(*dev_channels),
>> GFP_KERNEL);
>>          if (!dev_channels)
>>                  return -ENOMEM;
>>
>> diff --git a/drivers/iio/adc/xilinx-xadc-core.c
>> b/drivers/iio/adc/xilinx-xadc-core.c
>> index 292f2892d223..287df3bb951e 100644
>> --- a/drivers/iio/adc/xilinx-xadc-core.c
>> +++ b/drivers/iio/adc/xilinx-xadc-core.c
>> @@ -613,20 +613,17 @@ static int xadc_update_scan_mode(struct iio_dev
>> *indio_dev,
>>          const unsigned long *mask)
>>   {
>>          struct xadc *xadc = iio_priv(indio_dev);
>> -       size_t new_size, n;
>> +       size_t n;
>>          void *data;
>>
>>          n = bitmap_weight(mask, indio_dev->masklength);
>>
>> -       if (check_mul_overflow(n, sizeof(*xadc->data), &new_size))
>> -               return -ENOMEM;
>> -
>> -       data = devm_krealloc(indio_dev->dev.parent, xadc->data,
>> -                            new_size, GFP_KERNEL);
>> +       data = devm_krealloc_array(indio_dev->dev.parent, xadc->data,
>> +                                  n, sizeof(*xadc->data), GFP_KERNEL);
>>          if (!data)
>>                  return -ENOMEM;
>>
>> -       memset(data, 0, new_size);
>> +       memset(data, 0, n*sizeof(*xadc->data));
> 
> this is not correct coding style.

Oops, fixed in v2, thanks.

> 
> M