memmap pages can be allocated either from the memblock (boot) allocator
during early boot or from the buddy allocator.
When these memmap pages are removed via arch_remove_memory(), the
deallocation path depends on their source:
* For pages from the buddy allocator, depopulate_section_memmap() is
called, which also decrements the count of nr_memmap_pages.
* For pages from the boot allocator, free_map_bootmem() is called. But
it currently does not adjust the nr_memmap_boot_pages.
To fix this inconsistency, update free_map_bootmem() to also decrement
the nr_memmap_boot_pages count by invoking memmap_boot_pages_add(),
mirroring how free_vmemmap_page() handles this for boot-allocated pages.
This ensures correct tracking of memmap pages regardless of allocation
source.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 15995a352474 ("mm: report per-page metadata information")
Signed-off-by: Sumanth Korikkar <sumanthk@xxxxxxxxxxxxx>
---
mm/sparse.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/mm/sparse.c b/mm/sparse.c
index 3c012cf83cc2..d7c128015397 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -688,6 +688,7 @@ static void free_map_bootmem(struct page *memmap)
unsigned long start = (unsigned long)memmap;
unsigned long end = (unsigned long)(memmap + PAGES_PER_SECTION);
+ memmap_boot_pages_add(-1L * (DIV_ROUND_UP(end - start, PAGE_SIZE)));
vmemmap_free(start, end, NULL);
}
--
2.48.1
