cpuid_leaf(9)

💅 cpuid_leaf(9) — the cpuid_leaf page, bestie edition 🎀

okay so you're in the Kernel API Manual ✨ and this is literally the page for cpuid_leaf 💖

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🌸 NAME 🌸

cpuid_leaf — access parsed CPUID data, no cap 💫

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✨ SYNOPSIS ✨

cpuid_leaf (_cpuinfo , _leaf );

yes that's the whole thing, she's lowkey minimal 😌

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🫶 ARGUMENTS 🫶

• _cpuinfo — your CPU capability structure reference, aka a 'struct cpuinfo_x86' 💜 hand her over and she'll do the rest.
• _leaf — the CPUID leaf, and it's gotta be in compile-time 0xN format, mmkay? like e.g. 0x0, 0x2, 0x80000000 🌈

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🦋 DESCRIPTION 🦋

so basically she's giving cpuid_subleaf energy, except the CPUID subleaf is pinned to = 0 💅 that's the whole vibe.

Example usage, bestie, copy it exactly 👇

const struct leaf_0x0_0 *l0 = cpuid_leaf(c, 0x0);
if (!l0) {
        // Handle error
}

const struct leaf_0x80000000_0 *el0 = cpuid_leaf(c, 0x80000000);
if (!el0) {
        // Handle error
}

like look at that if (!l0) check — she said handle your error, periodt 😭🙈

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👑 SEE ALSO 👑

go read these next, fr fr 🌟 — kernel file ./arch/x86/include/asm/cpuid/api.h:

• cpuid_leaf_0x2(9)
• for_each_cpuid_0x2_desc(9)
• cpuid_subleaf(9)
• cpuid_leaf_raw(9)
• cpuid_subleaf_n(9)
• cpuid_subleaf_n_raw(9)
• cpuid_subleaf_count(9)

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ok that's the page!! now go parse some CPUID data and slay 💖🔥

and for the credits moment 🎀 — this cutie lives in ./arch/x86/include/asm/cpuid, dated October 2026, and the whole thing is cpuid_leaf(9) 💜 bye bestie 🦋