STRUCT PFRU_PAYLOAD_HDR(9)

✨ struct pfru_payload_hdr(9) ✨

okay bestie, welcome to the Kernel API Manual — we're looking at struct pfru_payload_hdr today and honestly? it's giving backstage pass energy 🎀

💖 NAME 💖

struct pfru_payload_hdr — the Capsule file payload header. yeah. that's it. that's the whole name. iconic of it tbh.

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🌸 SYNOPSIS 🌸

here's the whole struct, copy-paste-able, no cap:

struct pfru_payload_hdr {
    __u32 sig;
    __u32 hdr_version;
    __u32 hdr_size;
    __u32 hw_ver;
    __u32 rt_ver;
    __u8 platform_id[16];
    __u32 svn_ver;
 };

lowkey love how platform_id is the only one with a size on it — it's the main character of this struct fr fr 👑

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🦋 Members 🦋

let's go field by field, bestie, no skipping, we don't do that here 💅

• sig — the signature of this capsule file. like a little autograph so you know whose capsule it is ✨
• hdr_version — the revision of this header structure. version check, but make it header-flavored 💜
• hdr_size — the size of this header, and yes it includes the OemHeader bytes. don't forget those or the math will not math 😭
• hw_ver — the supported firmware version. the hw one. we stan a version field that knows what it is 🫶
• rt_ver — version of the code injection image. the rt one. very "different field, different job" of it 🌈
• platform_id — a platform specific GUID that says which platform this capsule image supports. 16 bytes of pure platform-identity realness 🧚

okay so real talk — svn_ver shows up in the struct up there in the SYNOPSIS, but this page doesn't give it a Members entry anywhere. so we're not gonna invent one, bestie. it exists, it's __u32, and that's all the page is willing to tell us 🙈 no cap, don't make stuff up.

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⭐ SEE ALSO ⭐

go read these next, they're all connected, iykyk 💫

• Kernel file ./include/uapi/linux/pfrut.h
• PFRU_IOC_SET_REV(9)
• PFRU_IOC_STAGE(9)
• PFRU_IOC_ACTIVATE(9)
• PFRU_IOC_STAGE_ACTIVATE(9)
• PFRU_IOC_QUERY_CAP(9)
• struct pfru_update_cap_info(9)
• struct pfru_com_buf_info(9)
• struct pfru_updated_result(9)
• struct pfrt_log_data_info(9)
• struct pfrt_log_info(9)
• PFRT_LOG_IOC_SET_INFO(9)
• PFRT_LOG_IOC_GET_INFO(9)
• PFRT_LOG_IOC_GET_DATA_INFO(9)

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and that's the whole page, bestie, you ate that 🍓

mwah — this one came from ./include/uapi/linux, dated October 2026, and it's filed under struct pfru_payload_hdr(9) in case you need to find it again. go forth and be iconic 💜🦋