On Wed, Dec 19, 2018 at 02:25:28PM +0000, Wei Yang wrote: > >- iter = round_up(iter + 1, 1<<compound_order(page)) - 1; > >+ skip_pages = (1 << compound_order(head)) - (page - head); > >+ iter = round_up(iter + 1, skip_pages) - 1; > > The comment of round_up says round up to next specified power of 2. And > second parameter must be a power of 2. > > Look skip_pages not satisfy this. I thought that gigantic pages were always allocated on 1GB aligned. At least alloc_gigantic_page() looks for 1GB range, aligned to that. But I see that in alloc_contig_range(), the boundaries can differ. Anyway, unless I am missing something, I think that we could just get rid of the round_up() and do something like: <-- skip_pages = (1 << compound_order(head)) - (page - head); iter = skip_pages - 1; --> which looks more simple IMHO. It should just work for 2MB and 1GB Hugepages. -- Oscar Salvador SUSE L3