Linux Kernel Replaced Dual VMA Structures with Maple Tree in Version 6.1

The Linux kernel manages a process's virtual memory through data structures stored in the memory descriptor (mm_struct), which tracks all Virtual Memory Areas (VMAs). Historically, the kernel maintained two parallel structures — a linked list for sequential traversal and a red-black tree for fast O(log n) lookups — requiring both to be updated on every VMA change. Starting with Linux 6.1, both structures were replaced by a single Maple Tree, which handles both traversal and fast lookup in one unified data structure. Unlike a red-black tree that holds one memory region per node, the Maple Tree stores multiple keys per node, similar to a B-tree, reducing overhead. This change simplifies kernel memory management and delivers better real-world performance while maintaining O(log n) time complexity for search, insert, and delete operations.