On Mon, Dec 05, 2016 at 05:31:01PM +0800, Michal Hocko wrote:

On Mon 05-12-16 17:17:07, Huang Shijie wrote:
[...]

quoted

   The failure is caused by:
    1) kernel fails to allocate a gigantic page for the surplus case.
       And the gather_surplus_pages() will return NULL in the end.

    2) The condition checks for some functions are wrong:
        return_unused_surplus_pages()
        nr_overcommit_hugepages_store()
        hugetlb_overcommit_handler()

OK, so how is this any different from gigantic (1G) hugetlb pages on

I think there is no different from gigantic (1G) hugetlb pages on
x86_64. Do anyone ever tested the 1G hugetlb pages in x86_64 with the "counter.sh"
before? 

x86_64? Do we need the same functionality or is it just 32MB not being
handled in the same way as 1G?

Yes, we need this functionality for gigantic pages, no matter it is
X86_64 or S390 or arm64, no matter it is 32MB or 1G. :)

But anyway, I will try to find some machine and try the 1G gigantic page
on ARM64.

Thanks
Huang Shijie