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I expected that event->owner was safe, but you are right. During my tests, I essentially attached an existing PID executed in an container (lxc), so I was not able to detect that race condition. I miss to re-validate all the other usage of CoreSight. > That said, one thing to note is that the ETM4x driver parses the event > config in each "event_start" call back, instead of doing once during the > event_init. If we move this to a onetime parsing at the event_init, with > additional checks in place (e.g, !is_kernel_event()), we may be able to > solve it. Thanks for this suggestion, I will try this approach and provide a v3. Regards, Julien