STRUCT SMM_VARIABLE_COMMUNICATE_HEADER(9)

💅 struct smm_variable_communicate_header — Kernel API Manual ✨

okay bestie, welcome to the Kernel API Manual ✨ this one's a lil struct page, and honestly? she's short but she matters. no cap.

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🎀 NAME 🎀

struct smm_variable_communicate_header — literally the struct used for SMM variable communication 🫶 that's her whole job and she does it slayfully.

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✨ SYNOPSIS ✨

ok so here's the shape of her, exactly as she is, copy-paste energy only:

struct smm_variable_communicate_header {
    size_t function;
    efi_status_t ret_status;
    u8 data[];
};

like, three members, zero drama. the way that trailing data[] is flexible-length and just vibing at the end? iconic.

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💖 Members 💖

• function — the function to call in Smm. like, which one do we invoke. this is the "who we calling bestie" field 👑
• ret_status — return status. the receipts, basically. it's an efi_status_t, so it tells you how things went 💀
• data — payload. the actual stuff being carried, a u8 array, flexible and ready to hold whatever 🎀

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🦋 SEE ALSO 🦋

the whole friend group, fr fr — go read these too:

• Kernel file ./drivers/firmware/efi/stmm/mm_communication.h
• struct efi_mm_communicate_header(9)
• struct smm_variable_access(9)
• struct smm_variable_payload_size(9)
• struct smm_variable_getnext(9)
• struct smm_variable_query_info(9)
• struct var_check_property(9)
• struct smm_variable_var_check_property(9)

iykyk — that's the entire squad right there 🌈

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okay and finally, the sign-off 💌 this page lives in the kernel tree at ./drivers/firmware/efi/stmm, it's dated October 2026, and the page itself is struct smm_v...icate_header(9) — yes the title got truncated in the corner, that's just how it renders, don't come for her 🙈 mwah, go read the structs, ily 🫶💜