This series amis to add hugetlb_free_vmemmap sysctl to enable the feature of freeing vmemmap pages of HugeTLB pages. v2: - Fix compilation when !CONFIG_MHP_MEMMAP_ON_MEMORY reported by kernel test robot <lkp@xxxxxxxxx>. - Move sysctl code from kernel/sysctl.c to mm/hugetlb_vmemmap.c. Muchun Song (3): mm: hugetlb: disable freeing vmemmap pages when struct page crosses page boundaries sysctl: allow to set extra1 to SYSCTL_ONE mm: hugetlb: add hugetlb_free_vmemmap sysctl Documentation/admin-guide/sysctl/vm.rst | 13 ++++++++++ include/linux/memory_hotplug.h | 9 +++++++ kernel/sysctl.c | 2 +- mm/hugetlb_vmemmap.c | 43 ++++++++++++++++++++++++++++++++- mm/hugetlb_vmemmap.h | 4 ++- mm/memory_hotplug.c | 5 ++++ 6 files changed, 73 insertions(+), 3 deletions(-) -- 2.11.0