Re: [PATCH] ASoC: Intel: SST: fix platform device leak on probe failure

[Guangshuo Li]

Hi Czarek,

Thanks for the review.

On Mon, 21 Sept 2026 at 17:31, Cezary Rojewski
<cezary.rojewski@xxxxxxxxx> wrote:
>
> On 9/21/2026 9:38 AM, Guangshuo Li wrote:
> > sst_acpi_probe() registers platform devices for the SST platform and
> > machine drivers using platform_device_register_data(), but does not
> > unregister them when later probe steps fail.
>
> s/machine drivers/machine board/
>
> The above paragraph alone is sufficient, please drop everything else in
> the commit message.  There is no need to write wall-of-text for a fix
> addressing a missing error path.  In case this wall was provided by an
> agent, relevant Assisted-by: tag is needed in the tag area.
>
> You can keep the very last sentence if you want to.
>
> > If machine device registration fails, the already registered SST platform
> > device is left registered. The same leak happens when
> > sst_platform_get_resources() or sst_context_init() fails after both
> > platform devices have been successfully registered.
> >
> > A registered platform device owns resources allocated by the platform
> > device core and must be released with platform_device_unregister() so
> > that the device reference is dropped and platform_device_release() can
> > free the backing platform_object.
> >
> > Unregister the created platform devices on all failure paths to restore
> > the missing cleanup.
> >
> > The issue was identified by a static analysis tool I developed and
> > confirmed by manual review.
> >
> > Fixes: caf94ed8629a ("ASoC: Intel: bytcr_rt5640: fixup DAI codec_name with HID")
> > Cc: stable@xxxxxxxxxxxxxxx
> > Signed-off-by: Guangshuo Li <lgs201920130244@xxxxxxxxx>
>
> For the commit title: please update to:
>         ASoC: Intel: atom: Fix (...)
>
> Provided both the commit title and message are updated, feel free to add:
> Reviewed-by: Cezary Rojewski <cezary.rojewski@xxxxxxxxx>
>
> > ---
> >  sound/soc/intel/atom/sst/sst_acpi.c | 13 ++++++++++---
> >  1 file changed, 10 insertions(+), 3 deletions(-)
> >
> > diff --git a/sound/soc/intel/atom/sst/sst_acpi.c b/sound/soc/intel/atom/sst/sst_acpi.c
> > index 73624e1b138a..a1f16083bd3d 100644
> > --- a/sound/soc/intel/atom/sst/sst_acpi.c
> > +++ b/sound/soc/intel/atom/sst/sst_acpi.c
> > @@ -352,7 +352,8 @@ static int sst_acpi_probe(struct platform_device *pdev)
> >       if (IS_ERR(mdev)) {
> >               dev_err(dev, "Failed to create machine device: %s\n",
> >                       mach->drv_name);
> > -             return PTR_ERR(mdev);
> > +             ret = PTR_ERR(mdev);
> > +             goto err_unregister_plat_dev;
> >       }
> >
> >       /* Fill sst platform data */
> > @@ -361,15 +362,21 @@ static int sst_acpi_probe(struct platform_device *pdev)
> >
> >       ret = sst_platform_get_resources(ctx);
> >       if (ret)
> > -             return ret;
> > +             goto err_unregister_mdev;
> >
> >       ret = sst_context_init(ctx);
> >       if (ret < 0)
> > -             return ret;
> > +             goto err_unregister_mdev;
> >
> >       sst_configure_runtime_pm(ctx);
> >       platform_set_drvdata(pdev, ctx);
> >       return ret;
> > +
> > +err_unregister_mdev:
> > +     platform_device_unregister(mdev);
> > +err_unregister_plat_dev:
> > +     platform_device_unregister(plat_dev);
> > +     return ret;
> >  }
>
> Looks like sst_acpi_remove() does not unregister the devices either.
> That could be fixed by enlisting devm_add_action_or_reset() in
> sst_acpi_probe() without altering sst_acpi_remove() at all.
>
> Would you mind sending a separate patch updating the function so both
> the error path and the driver-unload clean up the device objects?
>
>
> Kind regards,
> Czarek

I'll update the title to:

ASoC: Intel: atom: Fix platform device leak on probe failure

and trim the commit message as suggested, including the
s/machine drivers/machine board/ change. I'll also add your Reviewed-by.

For the separate cleanup patch, do you mean something like this?

+static void sst_unregister_platform_device(void *data)
+{
+        platform_device_unregister(data);
+}
+
        plat_dev = platform_device_register_data(...);
        if (IS_ERR(plat_dev))
                return PTR_ERR(plat_dev);
+
+       ret = devm_add_action_or_reset(dev, sst_unregister_platform_device,
+                                      plat_dev);
+       if (ret)
+               return ret;

        ...

        mdev = platform_device_register_data(...);
        if (IS_ERR(mdev))
                return PTR_ERR(mdev);
+
+       ret = devm_add_action_or_reset(dev, sst_unregister_platform_device,
+                                      mdev);
+       if (ret)
+               return ret;

This would let devres clean up both devices on later probe failure and on
driver unload, so the explicit unregister error paths from the first patch
would no longer be needed after this patch.

Would this be what you had in mind? If so, I'll follow Krzysztof's
suggestion, organize the related changes into a proper patch series,
and send a two-patch v2.

Thanks,
Guangshuo