mpol_misplaced(9)

💖 NAME 💖

okay so this page is all about mpol_misplaced(9) from the Kernel API Manual, and the whole point is to check whether current folio node is valid in policy. slay. 💅

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✨ SYNOPSIS ✨

int mpol_misplaced (struct folio *folio , struct vm_fault *vmf ,
       unsigned long addr );

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🎀 ARGUMENTS 🎀

• folio — the folio to be checked, bestie 👀
• vmf — structure describing the fault, literally the fault lore
• addr — virtual address in vma for shared policy lookup and interleave policy

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🦋 DESCRIPTION 🦋

So here's the vibe: it lookups the current policy node id for vma,addr and then “compare to” folio's node id. Policy determination “mimics” alloc_page_vma. It's called from fault path where we know the vma and faulting address. iykyk. ✨

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🌸 RETURN 🌸

It returns NUMA_NO_NODE if the page is in a node that is valid for this policy, or a suitable node ID to allocate a replacement folio from. periodt. 💖

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🌈 SEE ALSO 🌈

• Kernel file ./mm/mempolicy.c
• numa_nearest_node(9)
• nearest_node_nodemask(9)
• folio_can_map_prot_numa(9)
• alloc_pages_mpol(9)
• vma_alloc_folio(9)
• alloc_pages(9)
• mpol_shared_policy_init(9)
• mpol_parse_str(9)
• mpol_to_str(9)

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okay bye bestie 🫶 — this one comes from source/version ./mm, dated October 2026. mwah 💋✨