On Tue, Apr 21, 2026 at 02:54:35PM +0800, Muchun Song wrote: > > > > On Apr 21, 2026, at 12:15, Oscar Salvador <[email protected]> wrote: > > > > On Tue, Apr 21, 2026 at 10:20:44AM +0800, Muchun Song wrote: > >> 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]>
Reviewed-by: Oscar Salvador <[email protected]> > > Would not the call to __init_zone_device_page() from > > memmap_init_compound() take care of the subsequent pageblocks? > > > > No, it won't handle them automatically, as the page count from > compound_nr_pages doesn't cover the following pageblocks. Ok, I see. -- Oscar Salvador SUSE Labs
