Re: [PATCH v2] iio: adc: mxs-lradc: fix the order of two cleanup operations

[Dongliang Mu]

On 2023/4/23 18:50, Jonathan Cameron wrote:
> On Sun, 16 Apr 2023 19:47:45 -0700
> Jiakai Luo <jkluo@xxxxxxxxxxx> wrote:
>
> > Smatch reports:
> > drivers/iio/adc/mxs-lradc-adc.c:766 mxs_lradc_adc_probe() warn:
> > missing unwind goto?
> >
> > the order of three init operation:
> > 1.mxs_lradc_adc_trigger_init
> > 2.iio_triggered_buffer_setup
> > 3.mxs_lradc_adc_hw_init
> >
> > thus, the order of three cleanup operation should be:
> > 1.mxs_lradc_adc_hw_stop
> > 2.iio_triggered_buffer_cleanup
> > 3.mxs_lradc_adc_trigger_remove
> >
> > we exchange the order of two cleanup operations,
> > introducing the following differences:
> > 1.if mxs_lradc_adc_trigger_init fails, returns directly;
> > 2.if trigger_init succeeds but iio_triggered_buffer_setup fails,
> > goto err_trig and remove the trigger.
> >
> > In addition, we also reorder the unwind that goes on in the
> > remove() callback to match the new ordering.
> >
> > Fixes: 6dd112b9f85e ("iio: adc: mxs-lradc: Add support for ADC driver")
> > Signed-off-by: Jiakai Luo <jkluo@xxxxxxxxxxx>
> > Reviewed-by: Dongliang Mu <dzm91@xxxxxxxxxxx>
> If resending please state why.  I'm guessing on this occasion it was because
> you realised a fresh thread is expected for a new patch.
>
> Also, even if you are just amending the patch description, please increase
> the version number so that we can be sure we are looking at latest version.
>
> I already picked it from the earlier posting and this appears unchanged
> so all's well that ends well!
>
> Jonathan

Hi JC,

Jiakai originally would like to send a reminder about his patch, but 
mistakenly sent a v2 version.

Please ignore this v2 version since this version is the same with v1 
version.

Sorry for the mistake.

> > ---
> > The issue is found by static analysis and remains untested.
> > ---
> >   drivers/iio/adc/mxs-lradc-adc.c | 10 +++++-----
> >   1 file changed, 5 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/iio/adc/mxs-lradc-adc.c b/drivers/iio/adc/mxs-lradc-adc.c
> > index bca79a93cbe4..85882509b7d9 100644
> > --- a/drivers/iio/adc/mxs-lradc-adc.c
> > +++ b/drivers/iio/adc/mxs-lradc-adc.c
> > @@ -757,13 +757,13 @@ static int mxs_lradc_adc_probe(struct platform_device *pdev)
> >   
> >   	ret = mxs_lradc_adc_trigger_init(iio);
> >   	if (ret)
> > -		goto err_trig;
> > +		return ret;
> >   
> >   	ret = iio_triggered_buffer_setup(iio, &iio_pollfunc_store_time,
> >   					 &mxs_lradc_adc_trigger_handler,
> >   					 &mxs_lradc_adc_buffer_ops);
> >   	if (ret)
> > -		return ret;
> > +		goto err_trig;
> >   
> >   	adc->vref_mv = mxs_lradc_adc_vref_mv[lradc->soc];
> >   
> > @@ -801,9 +801,9 @@ static int mxs_lradc_adc_probe(struct platform_device *pdev)
> >   
> >   err_dev:
> >   	mxs_lradc_adc_hw_stop(adc);
> > -	mxs_lradc_adc_trigger_remove(iio);
> > -err_trig:
> >   	iio_triggered_buffer_cleanup(iio);
> > +err_trig:
> > +	mxs_lradc_adc_trigger_remove(iio);
> >   	return ret;
> >   }
> >   
> > @@ -814,8 +814,8 @@ static int mxs_lradc_adc_remove(struct platform_device *pdev)
> >   
> >   	iio_device_unregister(iio);
> >   	mxs_lradc_adc_hw_stop(adc);
> > -	mxs_lradc_adc_trigger_remove(iio);
> >   	iio_triggered_buffer_cleanup(iio);
> > +	mxs_lradc_adc_trigger_remove(iio);
> >
> >   	return 0;
> >   }