CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's core scheduling mechanism, specifically the pick_next_task() function, which can lead to improper handling of sibling run queues due to a race condition. This flaw may allow for the leakage of internal state information and potentially disrupt task scheduling, impacting system stability and performance. Organizations using affected versions of the Linux kernel should prioritize this issue, particularly those relying on core scheduling for performance optimization in multi-core environments.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: sched/core: Make core-sched flips wait for in-flight selections Core scheduling's pick_next_task() operates on all sibling rqs under one acquisition of the shared core-wide lock. A ->pick_task() that releases the rq lock leaves every sibling __lock momentarily free, letting __sched_core_flip(false) complete mid-selection and rebind rq_lockp() under it. The selection resumes on the split locks, touching sibling state it no longer protects, and __schedule() finally releases a lock that was never taken while leaking the one that was. Count in-flight core-wide selections in the leader's rq->core_pick_in_flight and make __sched_core_flip() wait for the count to drain. The count only changes under the shared lock, which the flip holds while sampling, so no other ordering is needed. The wait can repeat while selections overlap, but the flip backs off between samples and flips are rare cookie-lifetime events. sched_core_cpu_deactivate() moves the count to the new leader - a stale copy left behind would bias it forever if that CPU later returns as its own leader.