__vmalloc_node_range(9)

✨ __vmalloc_node_range — NAME ✨

okay so bestie, this page lives in the Kernel API Manual, section 9, and it's literally about allocating virtually contiguous memory 💖 that's the whole vibe. one function, nine arguments, zero chill.

---

🌸 SYNOPSIS 🌸

void * __vmalloc_node_range (unsigned long size , unsigned long align ,
unsigned long start , unsigned long end , gfp_t gfp_mask , pgprot_t prot
, unsigned long vm_flags , int node , const void *caller );

bestie look at this signature. look at it. nine params. it's giving "i have a lot going on but i'm handling it" 👑

---

🎀 ARGUMENTS 🎀

okay so literally every single one, in order, no skipping, i don't make the rules (i do, but whatever):

• size — how big the allocation is. the whole point, honestly.
• align — the alignment you want. desired. aspirational ✨
• start — where the vm area range starts.
• end — where the vm area range ends. bookends, yk?
• gfp_mask — the flags for the page level allocator. this one's the main character.
• prot — protection mask for the pages you're allocating. it's their armor 🛡️
• vm_flags — extra vm area flags, like e.g. VM_NO_GUARD. little extras, and we love that.
• node — which node to use for allocation, or NUMA_NO_NODE. no pressure, pick one 🫶
• caller — the caller's return address. like a little "who did this" tag.

---

🦋 DESCRIPTION 🦋

so here's the tea: it allocates enough pages to cover size from the page level allocator, using the gfp_mask flags, and then maps them into a contiguous virtual range with protection prot. boom. that's the whole thing. slay. 💅

💜 supported GFP classes (yes, the list is real, memorize her)

• GFP_KERNEL
• GFP_ATOMIC
• GFP_NOWAIT
• __GFP_RETRY_MAYFAIL
• __GFP_NORETRY
• GFP_NOFS
• GFP_NOIO

zone modifiers are not supported. no cap, don't try it. 🙈

and heads up, bestie: GFP_ATOMIC and GFP_NOWAIT are supported only by __vmalloc. like, specifically her. don't get it twisted.

🔥 retry modifiers, and this part is kinda finicky

• only __GFP_NOFAIL is fully supported. queen. no notes. 👑
• __GFP_NORETRY and __GFP_RETRY_MAYFAIL are supported with limitation — meaning the page tables are allocated with NOWAIT semantic, so they might fail under moderate memory pressure. it's giving "she's trying her best but the conditions are rough" 😭

🌈 the other little flag besties

• __GFP_NOWARN — use it to suppress failure messages. for when you simply do not wish to hear about it, honestly relatable.
• __GFP_SKIP_KASAN — use it to skip unpoisoning of mapped pages (this applies when prot=PAGE_KERNEL). very specific, very niche, very her.

⚠️ real talk: this can not be called from interrupt nor NMI contexts. like, at all. do not attempt. it will not go well and i will not be held responsible 💀

---

⭐ RETURN ⭐

the address of the area — or NULL on failure. that's it. either you got the address or you got nothing and you have to deal with that 🫠

---

🧚 SEE ALSO 🧚

okay this list is LONG, but i would never skip a single one of them because they're all icons in their own right. and it lives in the kernel file ./mm/vmalloc.c, which is basically the group chat these all hang out in. iykyk:

vunmap_range(9), vmap_pages_range(9), vm_area_map_pages(9), vm_area_unmap_pages(9), new_vmap_block(9), vm_unmap_aliases(9), vm_unmap_ram(9), vm_map_ram(9), vm_area_add_early(9), vm_area_register_early(9), get_vm_area(9), find_vm_area(9), remove_vm_area(9), vfree_atomic(9), vfree(9), vunmap(9), vmap(9), vmap_pfn(9), __vmalloc_node(9), vmalloc(9), vmalloc_huge_node(9), vzalloc(9), vmalloc_user(9), vmalloc_node(9), vzalloc_node(9), vrealloc_node_align(9), vmalloc_32(9), vmalloc_32_user(9), vread_iter(9), remap_vmalloc_range_partial(9), remap_vmalloc_range(9), pvm_find_va_enclose_addr(9), pvm_determine_end_from_reverse(9), pcpu_get_vm_areas(9), pcpu_free_vm_areas(9)

like. thirty-plus entries. she's connected. networking queen 🌈

---

<div align="center">💖</div>

okay that's the whole page!! mwah 🫶 it comes from the source ./mm, dated October 2026 — so jot that down, timestamp your receipts, and go allocate something virtually contiguous. periodt. 💅✨🎀