[PATCH] powercap: intel_rapl_tpmi: Handle PMU registration failure during probe

[PATCH] powercap: intel_rapl_tpmi: Handle PMU registration failure during probe

[Sumeet Pawnikar]

intel_rapl_tpmi_probe() invokes rapl_package_add_pmu() but it ignores
the return value, so a PMU registration failure may leave the driver
reporting probe success despite the PMU being absent, with no log
trace. Worse case scenario, the previously-added RAPL package would
not be torn down.

Add check for the return value, log the failure, undo the package
addition with rapl_remove_package() and fail the probe.

Signed-off-by: Sumeet Pawnikar <sumeet4linux@gmail.com>
---
 drivers/powercap/intel_rapl_tpmi.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/powercap/intel_rapl_tpmi.c b/drivers/powercap/intel_rapl_tpmi.c
index 7f41491d9cd1..8bc95310b542 100644
--- a/drivers/powercap/intel_rapl_tpmi.c
+++ b/drivers/powercap/intel_rapl_tpmi.c
@@ -414,7 +414,14 @@ static int intel_rapl_tpmi_probe(struct auxiliary_device *auxdev,
 		goto err;
 	}
 
-	rapl_package_add_pmu(trp->rp);
+	ret = rapl_package_add_pmu(trp->rp);
+	if (ret) {
+		dev_err(&auxdev->dev, "Failed to add RAPL PMU for Package%d, %d\n",
+			info->package_id, ret);
+		rapl_remove_package(trp->rp);
+		trp->rp = NULL;
+		goto err;
+	}
 
 	auxiliary_set_drvdata(auxdev, trp);
 
-- 
2.43.0

Re: [PATCH] powercap: intel_rapl_tpmi: Handle PMU registration failure during probe

[Rafael J. Wysocki]

On Fri, May 15, 2026 at 8:43 PM Sumeet Pawnikar <sumeet4linux@gmail.com> wrote:
>
> intel_rapl_tpmi_probe() invokes rapl_package_add_pmu() but it ignores
> the return value, so a PMU registration failure may leave the driver
> reporting probe success despite the PMU being absent, with no log
> trace. Worse case scenario, the previously-added RAPL package would
> not be torn down.
>
> Add check for the return value, log the failure, undo the package
> addition with rapl_remove_package() and fail the probe.
>
> Signed-off-by: Sumeet Pawnikar <sumeet4linux@gmail.com>
> ---
>  drivers/powercap/intel_rapl_tpmi.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/powercap/intel_rapl_tpmi.c b/drivers/powercap/intel_rapl_tpmi.c
> index 7f41491d9cd1..8bc95310b542 100644
> --- a/drivers/powercap/intel_rapl_tpmi.c
> +++ b/drivers/powercap/intel_rapl_tpmi.c
> @@ -414,7 +414,14 @@ static int intel_rapl_tpmi_probe(struct auxiliary_device *auxdev,
>                 goto err;
>         }
>
> -       rapl_package_add_pmu(trp->rp);
> +       ret = rapl_package_add_pmu(trp->rp);
> +       if (ret) {
> +               dev_err(&auxdev->dev, "Failed to add RAPL PMU for Package%d, %d\n",
> +                       info->package_id, ret);
> +               rapl_remove_package(trp->rp);
> +               trp->rp = NULL;
> +               goto err;
> +       }
>
>         auxiliary_set_drvdata(auxdev, trp);
>

Please see the sashiko.dev feedback on this:

https://sashiko.dev/#/patchset/20260515184250.228062-1-sumeet4linux%40gmail.com

and either address it or explain to me why it doesn't need to be addressed.

Thanks!