diff --git a/src/content/chapters/1-the-basics.mdx b/src/content/chapters/1-the-basics.mdx index 9042633..8a911b5 100644 --- a/src/content/chapters/1-the-basics.mdx +++ b/src/content/chapters/1-the-basics.mdx @@ -72,7 +72,7 @@ It's time to leap through our first rabbit hole into a land filled with syscalls ## Two Rings to Rule Them All -The *mode* (sometimes called privilege level or ring) a processor is in controls what it's allowed to do. Modern architectures have at least two options: kernel/supervisor mode and user mode. While an architecture might support more than two modes, only kernel mode and user mode are commonly used these days. +The *mode* (sometimes called privilege level or ring) controls what a processor is allowed to do. Modern architectures have at least two options: kernel/supervisor mode and user mode. While an architecture might support more than two modes, only kernel mode and user mode are commonly used these days. In kernel mode, anything goes: the CPU is allowed to execute any supported instruction and access any memory. In user mode, only a subset of instructions is allowed, I/O and memory access is limited, and many CPU settings are locked. Generally, the kernel and drivers run in kernel mode while applications run in user mode.