PFRU_IOC_QUERY_CAP(9)

💅 PFRU_IOC_QUERY_CAP(9) — like, the Kernel API Manual page, bestie ✨

okay so real quick, this is PFRU_IOC_QUERY_CAP(9) from the Kernel API Manual — yes the section 9 one, we're in kernel-internals land, stay close 🫶

🌸 NAME 🌸

PFRU_IOC_QUERY_CAP — literally just _IOR(PFRUT_IOCTL_MAGIC, 0x05, struct pfru_update_cap_info), no cap 💅

✨ SYNOPSIS ✨

PFRU_IOC_QUERY_CAP

that's it, that's the whole vibe 🎀

🔥 RETURN 🔥

bestie the return values are giving very much "short but iconic", so here they are, all three, no skips:

• 0 — success 🎉 slay, it worked
• -EINVAL — the query phase returns invalid result 😭 something's off in query town
• -EFAULT — the result fails to be copied to userspace 💀 the copy-out did not eat

🦋 DESCRIPTION 🦋

okay so what this actually does: it retrieves information on the Platform Firmware Runtime Update capability. and that information? it's a struct pfru_update_cap_info. that's the whole thing. iconic behavior honestly 👑

🌈 SEE ALSO 🌈

the friend group, all of them, in order, go say hi 🫶:

• 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)
• struct pfru_payload_hdr(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)

ngl this page lives at ./include/uapi/linux and it's dated October 2026, so yeah, future-dated queen behavior ⭐ and that's the whole manual page, mwah 💖 🧚‍♀️