Re: [PATCH v4 4/8] iio: core: Calculate alloc_size only once in iio_device_alloc()

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: David Lechner <dlechner@baylibre.com>
Cc: Vinod Koul <vkoul@kernel.org>,
	Linus Walleij <linus.walleij@linaro.org>,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	Mark Brown <broonie@kernel.org>,
	Kees Cook <keescook@chromium.org>,
	linux-arm-kernel@lists.infradead.org, dmaengine@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org,
	linux-spi@vger.kernel.org, netdev@vger.kernel.org,
	linux-hardening@vger.kernel.org,
	Jonathan Cameron <jic23@kernel.org>,
	Lars-Peter Clausen <lars@metafoo.de>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	"Gustavo A. R. Silva" <gustavoars@kernel.org>
Subject: Re: [PATCH v4 4/8] iio: core: Calculate alloc_size only once in iio_device_alloc()
Date: Wed, 28 Feb 2024 23:09:03 +0200	[thread overview]
Message-ID: <Zd-g7_Cl__Z291CQ@smile.fi.intel.com> (raw)
In-Reply-To: <CAMknhBGj_+hw0F-g3R6iY0HEooGH1a8gfj1hYx_Laj93OQbQwQ@mail.gmail.com>

On Wed, Feb 28, 2024 at 02:57:36PM -0600, David Lechner wrote:
> On Wed, Feb 28, 2024 at 2:49 PM Andy Shevchenko
> <andriy.shevchenko@linux.intel.com> wrote:

...

> > -       alloc_size = sizeof(struct iio_dev_opaque);
> > -       if (sizeof_priv) {
> > -               alloc_size = ALIGN(alloc_size, IIO_DMA_MINALIGN);
> > -               alloc_size += sizeof_priv;
> > -       }
> > +       if (sizeof_priv)
> > +               alloc_size = ALIGN(alloc_size, IIO_DMA_MINALIGN) + sizeof_priv;
> 
> Isn't this using alloc_size before it is assigned? Perhaps you meant this:
> 
>     alloc_size = ALIGN(sizeof(struct iio_dev_opaque),
> IIO_DMA_MINALIGN) + sizeof_priv;

However the end result of the series is correct, this is a good catch!
Thanks!

> > +       else
> > +               alloc_size = sizeof(struct iio_dev_opaque);

-- 
With Best Regards,
Andy Shevchenko