STRUCT MEI_EXT_HDR(9)

💅 struct mei_ext_hdr(9) — bestie, let me introduce you

okay so first things first, the page you're on is struct mei_ext_hdr(9) — that's the title, and it lives in the Kernel API Manual. Consider yourself formally introduced 🫶

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✨ NAME ✨

struct mei_ext_hdr — the extend header descriptor, aka a TLV situation. no cap, that's literally what it is. TLV = type/length/value and this little struct is the first two letters of that alphabet soup 💖

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🦋 SYNOPSIS 🦋

here's the shape of it, exactly as it is, don't come for me about the formatting:

struct mei_ext_hdr {
    u8 type;
    u8 length;
 };

two tiny fields. main character energy in eight bytes total. it's giving minimalist icon 👑

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🌸 Members 🌸

so these are the actual members, and yes I'm gonna tell you about each one because they both matter:

• type — this one's an enum mei_ext_hdr_type. that's the "T" in TLV, the whole personality of the descriptor.
• length — and this is the length excluding the descriptor itself. read that again: excluding the descriptor. not including. don't count it. this is the kind of detail that will absolutely bite you at 3am if you skim 😭

lowkey a vibe check reminder: length does NOT count the descriptor. write it on your hand. put it in your notes app. tattoo it. whatever works 🎀

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🔥 SEE ALSO 🔥

okay this is the part where the manpage flexes its entire friend group, and I'm listing every single one because nobody gets left behind 💜

the kernel file to go look at is ./drivers/misc/mei/hw.h, and then:

• enum mei_hbm_status(9)
• enum mei_ext_hdr_type(9)
• struct mei_ext_meta_hdr(9)
• struct mei_ext_hdr_vtag(9)
• mei_ext_begin(9)
• mei_ext_last(9)
• struct mei_ext_hdr_gsc_h2f(9)
• struct mei_ext_hdr_gsc_f2h(9)
• mei_ext_next(9)
• mei_ext_hdr_len(9)
• struct mei_msg_hdr(9)
• struct mei_hbm_cl_cmd(9)
• enum hbm_host_enum_flags(9)
• struct hbm_host_enum_request(9)
• struct mei_client_properties(9)
• struct hbm_add_client_request(9)
• struct hbm_add_client_response(9)
• struct hbm_power_gate(9)
• struct hbm_client_connect_request(9)
• struct hbm_client_connect_response(9)
• struct hbm_notification_request(9)
• struct hbm_notification_response(9)
• struct hbm_notification(9)
• struct hbm_dma_mem_dscr(9)
• struct hbm_dma_setup_request(9)
• struct hbm_dma_setup_response(9)
• struct hbm_dma_ring_ctrl(9)
• struct hbm_capability_request(9)
• struct hbm_capability_response(9)
• struct hbm_client_dma_map_request(9)
• struct hbm_client_dma_unmap_request(9)
• struct hbm_client_dma_response(9)

that's the whole squad. thirty-two entries, all invited, all seated at the table 🍓

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and that's the page!! mwah 💋 this one came from ./drivers/misc/mei and it's dated October 2026, so if you're reading it, hi from the future, you're doing amazing, slay ✨🌈👑