STRUCT MEI_EXT_HDR_VTAG(9)

💅 struct mei_ext_hdr_vtag(9) — the Kernel API Manual, bestie edition

okay so this is a page from the Kernel API Manual (section 9, the kernel-API girlies) and it's all about struct mei_ext_hdr_vtag — the extend header for vtag. yes that's really the whole name, she's short and she knows it ✨

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✨ NAME ✨

struct mei_ext_hdr_vtag — extend header for vtag. that's it, that's the whole vibe 🎀

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🌸 SYNOPSIS 🌸

bestie look at her, she's literally just three little fields:

struct mei_ext_hdr_vtag {
    struct mei_ext_hdr hdr;
    u8 vtag;
    u8 reserved;
 };

okay so there's a lil spacing quirk in the original ( }; with a space before the brace) and we're keeping it exactly, no cap, because that's how it's written 💀

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🦋 Members 🦋

• hdr — the standard extend header. she's the blueprint, the main character of the struct, the one who actually carries the extended-header energy 👑
• vtag — virtual tag. a u8 doing virtual-tag things. that's the assignment and she ate 🍓
• reserved — reserved. it's a u8 and it's on standby, sitting there being reserved, which is honestly iconic of it 🫶

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🌈 SEE ALSO 🌈

okay this is the long part and we are NOT skipping anybody, every single one of these gets their moment, periodt 💖

Kernel file ./drivers/misc/mei/hw.h plus a whole friend group of references:

• enum mei_hbm_status(9)
• enum mei_ext_hdr_type(9)
• struct mei_ext_hdr(9)
• struct mei_ext_meta_hdr(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)

like, look at that list. it's giving group project where everyone actually showed up 😭👑

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lowkey reminder bestie: vtag and reserved are both u8, and reserved is reserved. don't be out here using reserved fields for your own little experiments, the kernel will not be cute about it 🙈

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💜 okay that's the whole page!! shipped from ./drivers/misc/mei, dated October 2026, and the page herself is struct mei_ext_hdr_vtag(9). go be great, mwah 🎀🦋✨