Re: [PATCH 00/10] Fix confusion around MAX_ORDER

[Mel Gorman]

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