{"api_version":"1","generated_at":"2026-05-13T01:06:37+00:00","cve":"CVE-2026-43326","urls":{"html":"https://cve.report/CVE-2026-43326","api":"https://cve.report/api/cve/CVE-2026-43326.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-43326","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43326"},"summary":{"title":"sched_ext: Fix SCX_KICK_WAIT deadlock by deferring wait to balance callback","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Fix SCX_KICK_WAIT deadlock by deferring wait to balance callback\n\nSCX_KICK_WAIT busy-waits in kick_cpus_irq_workfn() using\nsmp_cond_load_acquire() until the target CPU's kick_sync advances. Because\nthe irq_work runs in hardirq context, the waiting CPU cannot reschedule and\nits own kick_sync never advances. If multiple CPUs form a wait cycle, all\nCPUs deadlock.\n\nReplace the busy-wait in kick_cpus_irq_workfn() with resched_curr() to\nforce the CPU through do_pick_task_scx(), which queues a balance callback\nto perform the wait. The balance callback drops the rq lock and enables\nIRQs following the sched_core_balance() pattern, so the CPU can process\nIPIs while waiting. The local CPU's kick_sync is advanced on entry to\ndo_pick_task_scx() and continuously during the wait, ensuring any CPU that\nstarts waiting for us sees the advancement and cannot form cyclic\ndependencies.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-08 14:16:42","updated_at":"2026-05-12 14:10:27"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/415cb193bb9736f0e830286c72a6fa8eb2a9cc5c","name":"https://git.kernel.org/stable/c/415cb193bb9736f0e830286c72a6fa8eb2a9cc5c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/c3a7903f65cf4c7fb0477eb0f8b94f326a47fe54","name":"https://git.kernel.org/stable/c/c3a7903f65cf4c7fb0477eb0f8b94f326a47fe54","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-43326","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43326","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 90e55164dad42c6546b698c031697b224a320834 c3a7903f65cf4c7fb0477eb0f8b94f326a47fe54 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 90e55164dad42c6546b698c031697b224a320834 415cb193bb9736f0e830286c72a6fa8eb2a9cc5c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.12 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"43326","cve":"CVE-2026-43326","epss":"0.000180000","percentile":"0.050790000","score_date":"2026-05-12","updated_at":"2026-05-13 00:11:53"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["kernel/sched/ext.c","kernel/sched/sched.h"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"c3a7903f65cf4c7fb0477eb0f8b94f326a47fe54","status":"affected","version":"90e55164dad42c6546b698c031697b224a320834","versionType":"git"},{"lessThan":"415cb193bb9736f0e830286c72a6fa8eb2a9cc5c","status":"affected","version":"90e55164dad42c6546b698c031697b224a320834","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["kernel/sched/ext.c","kernel/sched/sched.h"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.12"},{"lessThan":"6.12","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.19.*","status":"unaffected","version":"6.19.12","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.0","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.12","versionStartIncluding":"6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","versionStartIncluding":"6.12","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Fix SCX_KICK_WAIT deadlock by deferring wait to balance callback\n\nSCX_KICK_WAIT busy-waits in kick_cpus_irq_workfn() using\nsmp_cond_load_acquire() until the target CPU's kick_sync advances. Because\nthe irq_work runs in hardirq context, the waiting CPU cannot reschedule and\nits own kick_sync never advances. If multiple CPUs form a wait cycle, all\nCPUs deadlock.\n\nReplace the busy-wait in kick_cpus_irq_workfn() with resched_curr() to\nforce the CPU through do_pick_task_scx(), which queues a balance callback\nto perform the wait. The balance callback drops the rq lock and enables\nIRQs following the sched_core_balance() pattern, so the CPU can process\nIPIs while waiting. The local CPU's kick_sync is advanced on entry to\ndo_pick_task_scx() and continuously during the wait, ensuring any CPU that\nstarts waiting for us sees the advancement and cannot form cyclic\ndependencies."}],"providerMetadata":{"dateUpdated":"2026-05-11T22:22:24.156Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/c3a7903f65cf4c7fb0477eb0f8b94f326a47fe54"},{"url":"https://git.kernel.org/stable/c/415cb193bb9736f0e830286c72a6fa8eb2a9cc5c"}],"title":"sched_ext: Fix SCX_KICK_WAIT deadlock by deferring wait to balance callback","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-43326","datePublished":"2026-05-08T13:31:10.184Z","dateReserved":"2026-05-01T14:12:56.002Z","dateUpdated":"2026-05-11T22:22:24.156Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-08 14:16:42","lastModifiedDate":"2026-05-12 14:10:27","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"43326","Ordinal":"1","Title":"sched_ext: Fix SCX_KICK_WAIT deadlock by deferring wait to balan","CVE":"CVE-2026-43326","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"43326","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Fix SCX_KICK_WAIT deadlock by deferring wait to balance callback\n\nSCX_KICK_WAIT busy-waits in kick_cpus_irq_workfn() using\nsmp_cond_load_acquire() until the target CPU's kick_sync advances. Because\nthe irq_work runs in hardirq context, the waiting CPU cannot reschedule and\nits own kick_sync never advances. If multiple CPUs form a wait cycle, all\nCPUs deadlock.\n\nReplace the busy-wait in kick_cpus_irq_workfn() with resched_curr() to\nforce the CPU through do_pick_task_scx(), which queues a balance callback\nto perform the wait. The balance callback drops the rq lock and enables\nIRQs following the sched_core_balance() pattern, so the CPU can process\nIPIs while waiting. The local CPU's kick_sync is advanced on entry to\ndo_pick_task_scx() and continuously during the wait, ensuring any CPU that\nstarts waiting for us sees the advancement and cannot form cyclic\ndependencies.","Type":"Description","Title":"sched_ext: Fix SCX_KICK_WAIT deadlock by deferring wait to balan"}]}}}