CVE-2026-68421

In the Linux kernel, the following vulnerability has been resolved: sched_ext: Don't warn on core-sched forced idle in put_prev_task_scx() put_prev_task_scx() warns when a runnable task drops to a lower sched_class without SCX_OPS_ENQ_LAST, on the assumption that balance_one() would have kept it running. Core scheduling breaks that: a forced-idle SMT sibling reschedules through the core_pick fast path in pick_next_task(), which skips pick_task_scx() and thus balance_one(), so a runnable task can drop to idle with ENQ_LAST unset. Gate the warning on sched_cpu_cookie_match(): a cookie mismatch means core scheduling forced the idle, while a match (or core scheduling off) still catches a genuine missing-ENQ_LAST drop.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/2907e9d0f05b506dfd58aec589a23042a56ef36b
https://git.kernel.org/stable/c/b7d9c359e5cf867f7eb23df3bb1c6b9e58af24da
https://git.kernel.org/stable/c/e2f188cdbf8312289532c36eb4e9eb1c9544d43a

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-10 13:20

Updated : 2026-08-17 06:17

NVD link : CVE-2026-68421

Mitre link : CVE-2026-68421

CVE.ORG link : CVE-2026-68421

JSON object : View

Products Affected

No product.

CWE

No CWE.

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