perf subsystem

The perf subsystem is the Linux kernel's performance-monitoring and sampling infrastructure, handling interrupt handlers, per-task bookkeeping, and userland file descriptors via perf_event_open. A recent fix for CVE-2025-37747 addressed a race condition in the perf subsystem that could cause hosts to hang during sigtrap event teardown, a denial-of-service issue. This tag covers discussions about the perf subsystem's architecture, bugs, and security patches, particularly in enterprise and server environments where performance monitoring is critical. Topics include kernel fixes, race conditions, and safe teardown procedures for perf events.