The memmap_init_zone_device() function only initializes the migratetype
of the first pageblock of a compound page. If the compound page size
exceeds pageblock_nr_pages (e.g., 1GB hugepages with 2MB pageblocks),
subsequent pageblocks in the compound page remain uninitialized.

Move the migratetype initialization out of __init_zone_device_page()
and into a separate pageblock_migratetype_init_range() function. This
iterates over the entire PFN range of the memory, ensuring that all
pageblocks are correctly initialized.

Fixes: c4386bd8ee3a ("mm/memremap: add ZONE_DEVICE support for compound pages")
Signed-off-by: Muchun Song <[email protected]>
Reviewed-by: Mike Rapoport (Microsoft) <[email protected]>
---
 mm/mm_init.c | 43 ++++++++++++++++++++++++++++---------------
 1 file changed, 28 insertions(+), 15 deletions(-)

diff --git a/mm/mm_init.c b/mm/mm_init.c
index f9f8e1af921c..e2d8eae23aa3 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -674,6 +674,19 @@ static inline void fixup_hashdist(void)
 static inline void fixup_hashdist(void) {}
 #endif /* CONFIG_NUMA */
 
+static __meminit void pageblock_migratetype_init_range(unsigned long pfn,
+                                                      unsigned long nr_pages,
+                                                      int migratetype)
+{
+       unsigned long end = pfn + nr_pages;
+
+       for (pfn = pageblock_align(pfn); pfn < end; pfn += pageblock_nr_pages) {
+               init_pageblock_migratetype(pfn_to_page(pfn), migratetype, 
false);
+               if (IS_ALIGNED(pfn, PAGES_PER_SECTION))
+                       cond_resched();
+       }
+}
+
 /*
  * Initialize a reserved page unconditionally, finding its zone first.
  */
@@ -1011,21 +1024,6 @@ static void __ref __init_zone_device_page(struct page 
*page, unsigned long pfn,
        page_folio(page)->pgmap = pgmap;
        page->zone_device_data = NULL;
 
-       /*
-        * Mark the block movable so that blocks are reserved for
-        * movable at startup. This will force kernel allocations
-        * to reserve their blocks rather than leaking throughout
-        * the address space during boot when many long-lived
-        * kernel allocations are made.
-        *
-        * Please note that MEMINIT_HOTPLUG path doesn't clear memmap
-        * because this is done early in section_activate()
-        */
-       if (pageblock_aligned(pfn)) {
-               init_pageblock_migratetype(page, MIGRATE_MOVABLE, false);
-               cond_resched();
-       }
-
        /*
         * ZONE_DEVICE pages other than MEMORY_TYPE_GENERIC are released
         * directly to the driver page allocator which will set the page count
@@ -1122,6 +1120,9 @@ void __ref memmap_init_zone_device(struct zone *zone,
 
                __init_zone_device_page(page, pfn, zone_idx, nid, pgmap);
 
+               if (IS_ALIGNED(pfn, PAGES_PER_SECTION))
+                       cond_resched();
+
                if (pfns_per_compound == 1)
                        continue;
 
@@ -1129,6 +1130,18 @@ void __ref memmap_init_zone_device(struct zone *zone,
                                     compound_nr_pages(altmap, pgmap));
        }
 
+       /*
+        * Mark the block movable so that blocks are reserved for
+        * movable at startup. This will force kernel allocations
+        * to reserve their blocks rather than leaking throughout
+        * the address space during boot when many long-lived
+        * kernel allocations are made.
+        *
+        * Please note that MEMINIT_HOTPLUG path doesn't clear memmap
+        * because this is done early in section_activate()
+        */
+       pageblock_migratetype_init_range(start_pfn, nr_pages, MIGRATE_MOVABLE);
+
        pr_debug("%s initialised %lu pages in %ums\n", __func__,
                nr_pages, jiffies_to_msecs(jiffies - start));
 }
-- 
2.20.1


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