Hi: On 2021/2/9 11:39, Mike Kravetz wrote: > On 2/8/21 6:10 PM, Miaohe Lin wrote: >> Hi: >> On 2021/2/9 9:26, Mike Kravetz wrote: >>> On 2/8/21 12:37 AM, Miaohe Lin wrote: >>>> PageHead(page) is implicitly checked in set_page_huge_active() via the >>>> PageHeadHuge(page) check. So remove this explicit one. >>> >>> I do not disagree with the code change. However, this commit message >>> is not accurate. set_page_huge_active() no longer exists in the tree >>> you are changing. It was replaced with SetHPageMigratable. Also, the >>> VM_BUG_ON_PAGE(!PageHeadHuge(page), page) was removed in the process. >>> So, there is no redundant check. >>> >>> However, a quick audit of calling code reveals that all callers know they >>> are operating on a hugetlb head page. >>> >> >> So I should change the commit log like: >> >> All callers know they are operating on a hugetlb head page. So this VM_BUG_ON_PAGE >> can't catch anything useful. >> >> and send a v2. Right? > > Correct, > Will do. Thanks a lot.