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[v2,60/69] mm/mm_init: Check zone consistency on optimized vmemmap sections

Message ID 20260513132044.41690-14-songmuchun@bytedance.com (mailing list archive)
State Handled Elsewhere
Headers show
Series mm: Generalize HVO for HugeTLB and device DAX | expand

Commit Message

Muchun Song May 13, 2026, 1:20 p.m. UTC 
For vmemmap-optimized sections, the shared tail struct pages are reused
across compound pages and should already carry the expected zone and
node.

Warn in __init_single_page() if such a shared tail page is seen with a
different zone or node, which would indicate inconsistent initialization.

Signed-off-by: Muchun Song <songmuchun@bytedance.com>
---
 mm/mm_init.c | 3 +++
 1 file changed, 3 insertions(+)
diff mbox series

Patch

diff --git a/mm/mm_init.c b/mm/mm_init.c
index 4ea39392993b..95422e92ede8 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -605,6 +605,9 @@  void __meminit __init_single_page(struct page *page, unsigned long pfn,
 	if (!is_highmem_idx(zone))
 		set_page_address(page, __va(pfn << PAGE_SHIFT));
 #endif
+	VM_WARN_ON_ONCE(order_vmemmap_optimizable(pfn_to_section_order(pfn)) &&
+			page_zone_id(page + OPTIMIZED_FOLIO_VMEMMAP_NR_STRUCT_PAGES) !=
+			page_zone_id(page));
 }
 
 #ifdef CONFIG_NUMA