kunmap_high(9)

okay so bestie, we’re opening the kunmap_high(9) page from the Kernel API Manual, and no cap it’s a tiny one but she still ate. here’s the whole thing with zero details left behind 💖

🎀 NAME 🎀

kunmap_high — unmap a highmem page into memory. yep, that’s the whole NAME-section mission statement, slay.

✨ SYNOPSIS ✨

void kunmap_high (const struct page *page );

🫶 ARGUMENTS 🫶

• page — the struct page to unmap. that's the one and only argument, and she’s literally a struct page 💅

🌸 DESCRIPTION 🌸

so kunmap_high unmaps a highmem page into memory. and here’s the important caveat, bestie: if ARCH_NEEDS_KMAP_HIGH_GET is not defined, then this may be called only from user context. that’s the whole description, but it’s giving very “small function, big rules” energy 👑

⚠️ caveat cutie: ARCH_NEEDS_KMAP_HIGH_GET not being defined means “user context only” for calls to this. keep that in mind, iykyk.

🦋 SEE ALSO 🦋

the whole squad + the kernel file:

• Kernel file ./mm/highmem.c
• kmap_high(9)
• kmap_high_get(9)
• page_address(9)
• set_page_address(9)

mwah 💋 ok bye — this iconic little page is from source/version ./mm, dated October 2026, and it’s the kunmap_high(9) manual page. periodt ✨