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Date: Wed, 12 Nov 2025 15:15:34 +0000
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Subject: Re: [PATCH v2] coresight: etm-perf: Fix reference count leak in
 etm_setup_aux
To: Ma Ke <make24@iscas.ac.cn>, suzuki.poulose@arm.com,
 mike.leach@linaro.org, james.clark@linaro.org,
 alexander.shishkin@linux.intel.com, mathieu.poirier@linaro.org
Cc: coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org,
 linux-kernel@vger.kernel.org, akpm@linux-foundation.org,
 stable@vger.kernel.org
References: <20251112012405.11731-1-make24@iscas.ac.cn>
Content-Language: en-US
From: Leo Yan <leo.yan@arm.com>
In-Reply-To: <20251112012405.11731-1-make24@iscas.ac.cn>
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On 11/12/25 01:24, Ma Ke wrote:

> @@ -454,6 +454,11 @@ static void *etm_setup_aux(struct perf_event *event, void **pages,
>  		goto err;
>  
>  out:
> +	if (user_sink) {
> +		put_device(&user_sink->dev);
> +		user_sink = NULL;
> +	}

After searched kernel, I prefer to put device in coresight_get_sink_by_id().
Please refer acpi_dev_present() how to do that.

I would like Suzuki's confirmation in case I introduce noise.

Thanks,
Leo