Re: [PATCH] coresight: add verification process for coresight_etm_get_trace_id

[Suzuki K Poulose <suzuki.poulose@arm.com>]

On 10/03/2025 02:23, Jie Gan wrote:
> The coresight_etm_get_trace_id function is a global function. The
> verification process for 'csdev' is required prior to its usage.
> 
> Fixes: c367a89dec26 ("Coresight: Add trace_id function to retrieving the trace ID")
> Signed-off-by: Jie Gan <quic_jiegan@quicinc.com>
> ---
>   drivers/hwtracing/coresight/coresight-core.c | 7 +++++--
>   1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
> index bd0a7edd38c9..5a7cd2376e2d 100644
> --- a/drivers/hwtracing/coresight/coresight-core.c
> +++ b/drivers/hwtracing/coresight/coresight-core.c
> @@ -1616,9 +1616,12 @@ EXPORT_SYMBOL_GPL(coresight_remove_driver);
>   int coresight_etm_get_trace_id(struct coresight_device *csdev, enum cs_mode mode,
>   			       struct coresight_device *sink)
>   {
> -	int trace_id;
> -	int cpu = source_ops(csdev)->cpu_id(csdev);
> +	int cpu, trace_id;
> +
> +	if (csdev->type != CORESIGHT_DEV_TYPE_SOURCE && !source_ops(csdev)->cpu_id)

That must be :

	csdev->type != CORESIGHT_DEV_TYPE_SOURCE || !source_ops(csdev)->cpu_id)


Suzuki


> +		return -EINVAL;
>   
> +	cpu = source_ops(csdev)->cpu_id(csdev);
>   	switch (mode) {
>   	case CS_MODE_SYSFS:
>   		trace_id = coresight_trace_id_get_cpu_id(cpu);