https://nalar.dev/tags/userfaultfd/ Recent content in Userfaultfd on Nalar Hugo en-us Thu, 17 Sep 2026 00:00:00 +0000 https://nalar.dev/userfaultfd-moves-page-fault-resolution-into-userspace/ Thu, 17 Sep 2026 00:00:00 +0000 https://nalar.dev/userfaultfd-moves-page-fault-resolution-into-userspace/ <h1 id="userfaultfd-moves-page-fault-resolution-into-userspace">Userfaultfd Moves Page-Fault Resolution Into Userspace</h1> <p>A thread touches a registered virtual-memory page and stops before the access completes. Instead of resolving the fault entirely inside the kernel, Linux can report the event through a userfaultfd and let another userspace component decide when and with what content execution may continue. That design supports live migration, post-copy memory transfer, checkpointing, and related memory-management systems, but it also places a concurrency-sensitive decision point outside the faulting thread.</p>