We call this kernel saunters: How Apple rearranged its #XNU with exclaves
Based on the references to exclaves in XNU source for #Apple's M4 chips and the A18 used in iPhone 16, source argues exclaves form the basis of a significant redesign of XNU's security model.
"In iOS 18, exclaves refer to specific resources that are separated from the main iOS kernel (XNU) and cannot be accessed by it, even if the kernel is compromised," the researcher explained in a document.
https://www.theregister.com/2025/03/08/kernel_sanders_apple_rearranges_xnu/

Changes to Apple Silicon put the @AsahiLinux project at odds with adding support for the M4 chips
https://www.linux-magazine.com/Online/News/Asahi-Linux-Runs-into-Issues-with-M4-Support?utm_source=MLM
#Linux #Asahi #AppleSilicon #M4 #XNU #hypervisor

#Apple Darwin #OS and #XNU #Kernel Deep Dive - Tracing its evolution from Mach and #BSD roots to powering #macOS #iOS and Apple Silicon. This post explores the hybrid kernel’s design, its adaptation to new hardware and security paradigms, and why XNU remains a uniquely resilient and scalable foundation for Apple’s platforms https://tansanrao.com/blog/2025/04/xnu-kernel-and-darwin-evolution-and-architecture/

🌗 蘋果的 Darwin 作業系統與 XNU 核心深度解析
➤ 蘋果作業系統底層核心技術的演變與解析
✤ https://tansanrao.com/blog/2025/04/xnu-kernel-and-darwin-evolution-and-architecture/
本文深入探討了蘋果的 Darwin 作業系統及其核心 XNU 的架構演變，從 Mach 與 BSD 的起源，到如今驅動 macOS、iOS 和 Apple Silicon 的強大基礎。文章追溯了這款混合式核心的設計、對新硬體和安全模式的適應，以及 XNU 獨特的彈性和可擴展性。作者分享了個人深入研究 XNU 的心得，並詳細分析了其架構、排程、記憶體管理和虛擬化支援等關鍵技術。
+ 這篇文章真的寫得很深入，對於想了解 macOS 和 iOS 底層原理的人來說，非常有價值。
+ 以前只知道蘋果的系統很穩定，沒想到背後有這麼複雜的技術演進和架構設計，令人印象深刻。
#作業系統 #蘋果 #XNU #Darwin #核心技術

🖥️ Ah, another 42-minute snooze fest on Apple's #Darwin #OS - because who doesn't want to be serenaded by the sweet nothings of #Mach and #BSD kernels? 🎻 Spoiler alert: #XNU is still resilient and scalable, just like every other tech cliché #Apple has been peddling since the dawn of time. 🍏
https://tansanrao.com/blog/2025/04/xnu-kernel-and-darwin-evolution-and-architecture/ #techcliches #snoozefest #HackerNews #ngated

On #Apple #Exclaves (M4 and A18 based systems). Exclaves are a new set of #security features that represent a significant enhancement for XNU’s traditional monolithic kernel. Exclaves refer to resources that are isolated from #XNU, protected even if the #kernel is compromised. These resources are pre-defined when the OS is built, are identified by name or id, have different types, are initialised at boot time, and are organized into unique domains. #SPTM protects exclave memory from XNU with new exclave-specific page types. https://randomaugustine.medium.com/on-apple-exclaves-d683a2c37194