{"id":"CVE-2026-93220","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Keep kick_sync waiting on the rq's own CPU\n\nkick_sync_wait_bal_cb() assumes it runs on the rq's CPU from the\n__schedule() tail: the snapshots it compares aga…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Keep kick_sync waiting on the rq's own CPU\n\nkick_sync_wait_bal_cb() assumes it runs on the rq's CPU from the\n__schedule() tail: the snapshots it compares aga…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 4c95380701f58b8112f0b891de8d160e4199e19d < c736ea0fe7b4df920da6bd43a81c5eeecadcc8be","Linux >= 4c95380701f58b8112f0b891de8d160e4199e19d < e0253dd04beb03e79477c5ef4768b11135687206","Linux 6.19"],"published":"2026-09-24","updated":"2026-09-24","sourceUpdated":"2026-09-24T16:17:17.197","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-93220","references":[{"url":"https://git.kernel.org/stable/c/c736ea0fe7b4df920da6bd43a81c5eeecadcc8be","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e0253dd04beb03e79477c5ef4768b11135687206","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-24T15:45:56.668Z","slug":"CVE-2026-93220","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Keep kick_sync waiting on the rq's own CPU\n\nkick_sync_wait_bal_cb() assumes it runs on the rq's CPU from the\n__schedule() tail: the snapshots it compares against live in that CPU's\npercpu area and the busy-wait runs with the rq lock dropped and IRQs\nenabled.\n\nHowever, dispatch can now drop the rq lock while the callback sits queued,\nand rq lock takers in that window (the sched class change paths, the scx\ntask iterator) flush pending balance callbacks on release, running the\ncallback on a foreign CPU. Such a run compares against unrelated snapshots\nand can deadlock when the executing CPU is itself a wait target.\n\nBail on a foreign CPU and leave the wait state alone. The wait only observes\nprogress that the resched kicks already guarantee and the rq's next wait\npicks up the stale cpus_to_sync bits.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}