Re: [PATCH 2/2] coresight: Abort probe for missing CPU phandle

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

On 20/06/2019 14:45, Sai Prakash Ranjan wrote:
> Currently the coresight etm and cpu-debug drivers
> assume the affinity to CPU0 returned by coresight
> platform and continue the probe in case of missing
> CPU phandle. This is not true and leads to crash
> in some cases, so abort the probe in case of missing
> CPU phandle.
> 
> Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
> ---
>   drivers/hwtracing/coresight/coresight-cpu-debug.c | 3 +++
>   drivers/hwtracing/coresight/coresight-etm3x.c     | 3 +++
>   drivers/hwtracing/coresight/coresight-etm4x.c     | 3 +++
>   3 files changed, 9 insertions(+)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-cpu-debug.c b/drivers/hwtracing/coresight/coresight-cpu-debug.c
> index 07a1367c733f..43f32fa71ff9 100644
> --- a/drivers/hwtracing/coresight/coresight-cpu-debug.c
> +++ b/drivers/hwtracing/coresight/coresight-cpu-debug.c
> @@ -579,6 +579,9 @@ static int debug_probe(struct amba_device *adev, const struct amba_id *id)
>   		return -ENOMEM;
>   
>   	drvdata->cpu = coresight_get_cpu(dev);
> +	if (drvdata->cpu == -ENODEV)
> +		return -ENODEV;

if (drvdata->cpu < 0)
	return drvdata->cpu;

Same everywhere below ?

Also, I would like to hear Mathieu's thoughts on this change. If he's OK
with it:

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> with the change above.