Re: [PATCH v3 5/5] arm64: dts: qcom: glymur: use Aggregator TNOC compatible

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] System trace ID leak on device unbind or module removal for Aggregator TNOC platform devices because `tnoc_platform_remove` fails to free the allocated ID.
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commit e1acaab1b46a7af95def9021d30728ac2de6b44a
Author: Jie Gan <jie.gan@oss.qualcomm.com>

arm64: dts: qcom: glymur: use Aggregator TNOC compatible

This commit updates the traceNoC node in the glymur device tree to use the
qcom,coresight-agtnoc compatible. This ensures the node probes as an 
Aggregator TNOC and properly allocates a system trace ID.

> diff --git a/arch/arm64/boot/dts/qcom/glymur.dtsi b/arch/arm64/boot/dts/qcom/glymur.dtsi
> --- a/arch/arm64/boot/dts/qcom/glymur.dtsi
> +++ b/arch/arm64/boot/dts/qcom/glymur.dtsi
> @@ -6038,12 +6038,12 @@ qm_tpdm_out: endpoint {
[ ... ]
> -		itnoc@11200000  {
> -			compatible = "qcom,coresight-itnoc";
> +		tn@11200000 {
> +			compatible = "qcom,coresight-agtnoc";

[Severity: High]
This is a pre-existing issue, but by switching this node to the
qcom,coresight-agtnoc compatible, does this expose a system trace ID leak on
device unbind?

When a platform device matching this compatible is bound, it allocates a
system trace ID. However, if the device is subsequently unbound via sysfs or
module unload, the current cleanup path fails to free the ID:

drivers/hwtracing/coresight/coresight-tnoc.c:tnoc_platform_remove() {
	struct trace_noc_drvdata *drvdata = platform_get_drvdata(pdev);

	coresight_unregister(drvdata->csdev);
	pm_runtime_disable(&pdev->dev);
}

Unlike the AMBA counterpart trace_noc_remove(), this platform removal function
lacks a call to coresight_trace_id_put_system_id(drvdata->atid). 

Since the global trace ID pool is strictly limited, could unbinding this newly
converted device repeatedly exhaust the system trace IDs and prevent further
CoreSight trace sessions from succeeding?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260630-fix-tracenoc-probe-issue-v3-0-7201e1841e94@oss.qualcomm.com?part=5