[PATCH] coresight: Only register perf symlink for sinks with alloc_buffer
Suzuki K Poulose
suzuki.poulose at arm.com
Mon Jun 30 03:37:48 PDT 2025
On 30/06/2025 11:26, Yuanfang Zhang wrote:
> Ensure that etm_perf_add_symlink_sink() is only called for devices
> that implement the alloc_buffer operation. This prevents invalid
> symlink creation for dummy sinks that do not implement alloc_buffer.
>
> Without this check, perf may attempt to use a dummy sink that lacks
> alloc_buffer operationsu to initialise perf's ring buffer, leading
> to runtime failures.
>
> Fixes: 9d3ba0b6c0569 ("Coresight: Add coresight dummy driver")
> Signed-off-by: Yuanfang Zhang <quic_yuanfang at quicinc.com>
> ---
> drivers/hwtracing/coresight/coresight-core.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
> index fa758cc21827552a5c97b6bdd05d22dec4994b22..fddf04c5ee46eb4d559416296f7e85ce6c5689fa 100644
> --- a/drivers/hwtracing/coresight/coresight-core.c
> +++ b/drivers/hwtracing/coresight/coresight-core.c
> @@ -1374,8 +1374,9 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
> goto out_unlock;
> }
>
> - if (csdev->type == CORESIGHT_DEV_TYPE_SINK ||
> - csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) {
> + if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
> + csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) &&
> + sink_ops(csdev)->alloc_buffer) {
> ret = etm_perf_add_symlink_sink(csdev);
>
> if (ret) {
>
Looks good to me, I will queue this
Suzuki
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