mtrr_bp_init(9)

💖 mtrr_bp_init — a Kernel API Manual moment 💖

okay so bestie, welcome to the Kernel API Manual page for mtrr_bp_init(9) — yes that's the manual name, and yes we are doing this, because this tiny little function is lowkey carrying the whole boot process on its back 🫶

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✨ NAME ✨

mtrr_bp_init — initialize MTRRs on the boot CPU 💅

🌸 SYNOPSIS 🌸

void mtrr_bp_init (void );

🎀 ARGUMENTS 🎀

• void — no arguments. nada. zero. the function said "i don't need input, i am the input" 😭

🦋 DESCRIPTION 🦋

so here's the tea ☕ — this needs to be called early. like, early early. before any of the other CPUs are initialized, i.e. before smp_init. the way that this is genuinely a "me first, everyone else later" situation and honestly? main character energy 👑

no cap, if you're calling this late you're doing it wrong, and the vibes will be rancid 🙈

🧚 SEE ALSO 🧚

Kernel file ./arch/x86/kernel/cpu/mtrr/mtrr.c — go read it, it's giving lore ✨

• mtrr_rendezvous_handler(9)
• set_mtrr(9)
• mtrr_add_page(9)
• mtrr_add(9)
• mtrr_del_page(9)
• mtrr_del(9)
• arch_phys_wc_add(9)
• mtrr_save_state(9)

all the MTRR besties in one group chat, we love a friend group 🌈

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periodt 💀 call it early or don't call it at all, iykyk

and that's the page!! brought to you by the ./arch/x86/kernel/cpu/mtrr directory (the source/version bestie) and dated October 2026 — mwah, love u, go initialize those MTRRs 🍓💜