Notifier and Folio Deadlock Issue in Linux Kernel

CVE-2025-37868

Summary

A deadlock issue has been identified within the Linux kernel, specifically involving interactions between notifier callbacks and folio locks during memory management operations. When the migrate_pages_batch function holds onto folio locks, it can trigger a situation where notifier locks are simultaneously requested, leading to potential system instability. This issue arises when the page access and dirty marking procedures overlap, with critical timing causing contention between multiple processes. The kernel developers have mitigated this risk by eliminating the unnecessary marking of pages as accessed or dirty, thereby ensuring smoother operation without compromising functionality.

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