Към съдържанието
Търсене

CVE-2026-89756: Linux

Няма оценка

CVSS

Няма данни

Вероятност да бъде експлоатирана в следващите 30 дни (EPSS)

Няма потвърждение

Атакува се

Няма данни

Време до експлоатация

    Описание

    Оригинално описание

    In the Linux kernel, the following vulnerability has been resolved: mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch() migrate_pages_batch() unmaps each folio before moving it, and every unmap runs the mmu_notifier invalidate callbacks. On KVM hosts try_to_migrate() ends up in kvm_mmu_notifier_invalidate_range_start() -> tdp_mmu_zap_leafs(), which is expensive, so unmapping a large batch keeps the CPU busy for a long time. The loop already calls cond_resched(), but on PREEMPTION kernels that is a no-op, and involuntary preemption is not a Tasks-RCU quiescent state. A long batch therefore never reports a quiescent state, and the migrating task (e.g. kcompactd) becomes a Tasks-RCU holdout, stalling the Tasks-RCU grace period for minutes, which is common at Meta fleet: INFO: rcu_tasks detected stalls on tasks: 0000000055349ecc: .. nvcsw: 1157401/1157401 holdout: 1 idle_cpu: -1/56 task:kcompactd0 state:R running task Call Trace: tdp_mmu_zap_leafs tdp_mmu_next_root gfn_to_pfn_cache_invalidate_start kvm_mmu_notifier_invalidate_range_start __mmu_notifier_invalidate_range_start try_to_migrate_one try_to_migrate migrate_pages_batch migrate_pages compact_zone compact_node kcompactd kthread Use cond_resched_tasks_rcu_qs() so a quiescent state is reported even when cond_resched() does nothing. This has also been discussed at [1]

    Засегнати продукти

    • Linux Linux: 8315f42295d2667a7f942f154b73a86fd7cb2227 преди 8c6d63d434ebb85c6cf3dac1e70a171b183c6614; 8315f42295d2667a7f942f154b73a86fd7cb2227 преди 4757542649af56d894e25e30f57cd497dffad53f; 8315f42295d2667a7f942f154b73a86fd7cb2227 преди 4996a7bc01ef35570664854dac2530c604981039; 8315f42295d2667a7f942f154b73a86fd7cb2227 преди 5dc0daff0341c6baba19c38f47d299ac831d7e99; 8315f42295d2667a7f942f154b73a86fd7cb2227 преди 66734981b4d3c105223a13c827c9c73be18d91ad; 8315f42295d2667a7f942f154b73a86fd7cb2227 преди efe8f86c0916f0f74eea74ae21a3b37f728c6bad
    • Linux Linux: 3.18; преди 3.18; 6.1.188 до 6.1.*; 6.6.157 до 6.6.*; 6.12.109 до 6.12.*; 6.18.50 до 6.18.*; 7.2.4 до 7.2.*; 7.3 до *

    История

    • 11 септември 2026 Публикувано

    Други уязвимости в Linux Linux

    Първоизточници

    CVE-2026-89756: Linux | freedomonline.bg