memblock_phys_free(9)

💅 memblock_phys_free(9) — Kernel API Manual, bestie edition ✨

okay so this is a page from the Kernel API Manual, and honestly? it's a little baddie with one job and it does it. it hands boot memory back to the system, and it does it flawlessly. let's get into it 🫶

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🌸 NAME 🌸

memblock_phys_free — free boot memory block

like, the whole personality is right there in the name. free. boot memory block. iconic, no notes 💖

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✨ SYNOPSIS ✨

int __init_memblock memblock_phys_free (phys_addr_t base , phys_addr_t size );

look at that signature. int return, __init_memblock annotation, two phys_addr_t args. it's giving "small function, big responsibilities" and we stan 😭

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🎀 ARGUMENTS 🎀

• base — the phys starting address of the boot memory block. like, where does this block even begin, bestie. this is the answer 📍
• size — size of the boot memory block in bytes. yep, plain old bytes, no fancy units, no vibes-based measurement. just bytes 🌈

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💫 DESCRIPTION 💫

so here's the tea: this frees a boot memory block that was previously allocated by the memblock_phys_alloc_xx API. allocated it before? we're un-allocating it now. balance restored, karma clean ✨

and the detail you actually need to remember: if called after the buddy allocator is available, the memory is released to the buddy allocator. like, the buddy allocator is up and running, so the memory doesn't just vanish — it goes home to buddy. it's a whole handoff situation 🤝

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🦋 SEE ALSO 🦋

okay, this list is long, but every single one of these is a real one, so let's go. no skipping, we don't do that here 💅

• Kernel file ./mm/memblock.c memblock overview(9)
• __memblock_find_range_bottom_up(9)
• __memblock_find_range_top_down(9)
• memblock_find_in_range_node(9)
• memblock_find_in_range(9)
• memblock_discard(9)
• memblock_double_array(9)
• memblock_merge_regions(9)
• memblock_insert_region(9)
• memblock_add_range(9)
• memblock_add_node(9)
• memblock_add(9)
• memblock_validate_numa_coverage(9)
• memblock_isolate_range(9)
• memblock_free(9)
• memblock_setclr_flag(9)
• memblock_mark_hotplug(9)
• memblock_clear_hotplug(9)
• memblock_mark_mirror(9)
• memblock_mark_nomap(9)
• memblock_clear_nomap(9)
• memblock_reserved_mark_noinit(9)
• memblock_reserved_mark_kern(9)
• memblock_mark_kho_scratch(9)
• memblock_clear_kho_scratch(9)
• __next_mem_range(9)
• __next_mem_range_rev(9)
• memblock_set_node(9)
• memblock_alloc_range_nid(9)
• memblock_phys_alloc_range(9)
• memblock_phys_alloc_try_nid(9)
• memblock_alloc_internal(9)
• memblock_alloc_exact_nid_raw(9)
• memblock_alloc_try_nid_raw(9)
• memblock_alloc_hugetlb(9)
• memblock_alloc_try_nid(9)
• __memblock_alloc_or_panic(9)
• memblock_estimated_nr_free_pages(9)
• memblock_is_region_memory(9)
• memblock_is_region_reserved(9)
• memblock_free_all(9)
• reserve_mem_find_by_name(9)
• reserve_mem_release_by_name(9)

that's the whole friend group. say hi to all of them or don't, but they're all in the group chat 👑

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quick vibe check before you go: every name above is exactly as written, so if you're grepping for one, you've got the spelling right here. no autocorrect behavior in this house 🙈

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and that's the page, bestie!! 🌈 this one ships out of the ./mm source directory, version vibes dated October 2026 — so mark your calendar, screenshot this, send it to the group chat, and go free some boot memory 💖🎀🦋✨👑