[Verse 1] Deep beneath your desktop lies a fortress made of code Two kingdoms split by iron walls, each with its own mode User space up high and bright, where applications play Kernel space below the gate, where hardware rules the day [Chorus] Ring zero holds the crown, ring three waits above Privilege separation keeps the boundaries thereof System calls the only bridge across the great divide Kernel space protects us all, user space can't hide [Verse 2] Your browser clicks and music streams all dance in ring three land But when they need to touch a file, they raise their humble hand The kernel checks credentials first, then grants or denies access No application gets direct control of precious resources [Chorus] Ring zero holds the crown, ring three waits above Privilege separation keeps the boundaries thereof System calls the only bridge across the great divide Kernel space protects us all, user space can't hide [Verse 3] Device drivers need the throne, they cannot work restricted Direct hardware manipulation keeps them kernel addicted Memory management below, virtual addressing schemes Protected mode enforcement guards our computational dreams [Bridge] Context switch between the realms Trap instructions change the helms From user mode to supervisor Kernel becomes the sole advisor [Chorus] Ring zero holds the crown, ring three waits above Privilege separation keeps the boundaries thereof System calls the only bridge across the great divide Kernel space protects us all, user space can't hide [Outro] Two kingdoms in one machine Separated but serene Architecture's sacred trust Ring levels we can't adjust
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