On Wed, Mar 15, 2023 at 02:31:23PM +0300, Kirill A. Shutemov wrote: > MAX_ORDER currently defined as number of orders page allocator supports: > user can ask buddy allocator for page order between 0 and MAX_ORDER-1. > > This definition is counter-intuitive and lead to number of bugs all over > the kernel. > > Fix the bugs and then change the definition of MAX_ORDER to be > inclusive: the range of orders user can ask from buddy allocator is > 0..MAX_ORDER now. > Acked-by: Mel Gorman <mgorman@xxxxxxx> Overall looks sane other than the fixups that need to be added as flagged by LKP. There is a mild risk for stable backports that reference MAX_ORDER but that's the responsibilty of who is doing the backport. There is a mild risk of muscle memory adding off-by-one errors for new code using MAX_ORDER but it's low. -- Mel Gorman SUSE Labs