Re: [PATCH v12 19/28] coresight: Save active path for system tracers

On Fri, May 15, 2026 at 11:54:22AM +0100, Suzuki K Poulose wrote:

[...]

...

• /*

• * Update the path pointer until after the source is enabled to avoid
  

• * races where multiple paths attempt to enable the same source.
  

• *
  

• * Do not set the path pointer here for per-CPU sources; set it locally
  

• * on the CPU instead. Otherwise, there is a window where the path is
  

• * enabled but the pointer is not yet set, causing CPU PM notifiers to
  

• * miss PM operations due to reading a NULL pointer.
  

• */
  

• if (!coresight_is_percpu_source(csdev))

• csdev->path = path;
  

Do we need to specail case this for non-percpu sources ? We could always let the driver save/clear the path leaving the core out of it. We can fix it separately from this series in a follow up patch.

This patch has a big reason is for patch 22. After saving csdev->path, then patch 22 can totally remove IDR cache related things.

Otherwise, we can drop this patch and patch 22, this wouldn't impact CPU PM stuffs.

Thanks, Leo