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To:     Jonathan Cameron <jic23@kernel.org>
Cc:     Lars-Peter Clausen <lars@metafoo.de>, ldv-project@linuxtesting.org,
        Peter Meerwald-Stadler <pmeerw@pmeerw.net>,
        Alexandru Ardelean <alexandru.ardelean@analog.com>,
        linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org
From:   Pavel Andrianov <andrianov@ispras.ru>
Subject: A potential data race in drivers/iio/adc/berlin2-adc.ko
Message-ID: <e11a245e-95ed-eff0-05a8-264f7598672f@ispras.ru>
Date:   Thu, 18 Mar 2021 11:07:10 +0300
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Hi,

berlin2_adc_probe [1] registers two interrupt handlers: berlin2_adc_irq [2]
and berlin2_adc_tsen_irq [3]. The interrupt handlers operate with the 
same data, for example, modify
priv->data with different masks:

priv->data &= BERLIN2_SM_ADC_MASK;
and
priv->data &= BERLIN2_SM_TSEN_MASK;

If the two interrupt handlers are executed simultaneously, a potential 
data race takes place. So, the question is if the situation is possible. 
For example, in the case of the handlers are executed on different CPU 
cores.

Best regards,
Pavel

[1] 
https://elixir.bootlin.com/linux/latest/source/drivers/iio/adc/berlin2-adc.c#L283 

[2] 
https://elixir.bootlin.com/linux/latest/source/drivers/iio/adc/berlin2-adc.c#L239 

[3] 
https://elixir.bootlin.com/linux/latest/source/drivers/iio/adc/berlin2-adc.c#L259