insn_get_displacement(9)

💅 insn_get_displacement 💅

okay so this is a lil page from the Kernel API Manual (section 9, kernel API girlies rise 🫶) and it's literally about pulling the displacement out of an instruction. that's it. that's the vibe. let's get into it ✨

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🌸 NAME 🌸

insn_get_displacement — get the displacement of instruction. no cap, that's the whole job 💖

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✨ SYNOPSIS ✨

int insn_get_displacement (struct insn *insn );

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🎀 ARGUMENTS 🎀

• insn — the struct insn that's holding your instruction. she's the main character here, the whole struct, the carrier of the instruction periodt 💅

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🦋 DESCRIPTION 🦋

so here's the tea ☕ — if necessary, it first collects the instruction up to and including the SIB byte. like, it does the homework first if it has to, then it does the thing. and the displacement value? it is sign-expanded, which is exactly the kind of detail you do NOT want to forget, bestie 😭

SIB = scale-index-base, iykyk 🔥 and yes it's capitalised in the original vibe, keep it that way.

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🌈 RETURN 🌈

• 0 — decoding succeeded 🎉 slay, it worked
• < 0 — otherwise 💀 it did not

lowkey important: the < 0 is an "otherwise" situation, meaning anything negative = not-success. it's not < 0 as some cute little side note, it's the entire failure bucket 🫶

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👑 SEE ALSO 👑

all of these live in the kernel file ./tools/arch/x86/lib/insn.c — bestie, go read the source, she ate 💅

• insn_init(9)
• insn_get_prefixes(9)
• insn_get_opcode(9)
• insn_get_modrm(9)
• insn_rip_relative(9)
• insn_get_sib(9)
• insn_get_immediate(9)
• insn_get_length(9)
• insn_decode(9)

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and that's the whole page, no crumbs left 🍓

sign-off time, bestie: this one's stamped ./tools/arch/x86/lib, dated October 2026, and it's filed under insn_get_displacement(9) — screenshot it, cite it, live by it 💜🧚‍♀️