Re: [PATCH] iio: imu: st_lsm6dsx: Fix check for invalid samples from FIFO

[Andy Shevchenko]

On Wed, Jan 21, 2026 at 03:05:54PM +0100, Francesco Lavra wrote:
> On Wed, 2026-01-21 at 14:47 +0200, Andy Shevchenko wrote:
> > On Wed, Jan 21, 2026 at 12:27:57PM +0100, Francesco Lavra wrote:

...

> > >  st_lsm6dsx_push_tagged_data(struct st_lsm6dsx_hw *hw, u8 tag,
> > >                             u8 *data, s64 ts)
> > >  {
> > > -       s16 val = le16_to_cpu(*(__le16 *)data);
> > >         struct st_lsm6dsx_sensor *sensor;
> > >         struct iio_dev *iio_dev;
> > >  
> > >         /* invalid sample during bootstrap phase */
> > > -       if (val >= ST_LSM6DSX_INVALID_SAMPLE)
> > > +       if ((tag == ST_LSM6DSX_GYRO_TAG || tag == ST_LSM6DSX_ACC_TAG)
> > > &&
> > > +           (s16)le16_to_cpup((__le16 *)data) >=
> > > ST_LSM6DSX_INVALID_SAMPLE)
> > 
> > Since data is u8 *, it might appear on unaligned addresses and the proper
> > conversion here is to use get_unaligned_le16() without any of those ugly
> > castings.
> 
> data here corresponds to iio_buff in st_lsm6dsx_read_tagged_fifo(), which
> is declared as __aligned(8), so it cannot appear on unaligned addresses.

You know that, compiler might not. If you sure, you should change u8 *data
to be __le16 *data in the function parameter. Until it's u8 *, the
get_unaligned_le16() is the error free thing to achieve that.

> > >                 return -EINVAL;

-- 
With Best Regards,
Andy Shevchenko