Re: [RFC PATCH v2 2/2] arm64 Kconfig: Select gigantic page

From: Catalin Marinas
Date: Mon Aug 22 2016 - 06:00:54 EST


On Mon, Aug 22, 2016 at 10:03:58AM +0200, Michal Hocko wrote:
> On Mon 22-08-16 10:56:43, Xie Yisheng wrote:
> > Arm64 supports gigantic page after
> > commit 084bd29810a5 ("ARM64: mm: HugeTLB support.")
> > however, it got broken by
> > commit 944d9fec8d7a ("hugetlb: add support for gigantic page
> > allocation at runtime")
> >
> > This patch selects ARCH_HAS_GIGANTIC_PAGE to make this
> > function can be used again.
>
> I haven't double checked that the above commit really broke it but if
> that is the case then
>
> Fixes: 944d9fec8d7a ("hugetlb: add support for gigantic page allocation at runtime")
>
> would be nice as well I guess. I do not think that marking it for stable
> is really necessary considering how long it's been broken and nobody has
> noticed...

I'm not sure that commit broke it. The gigantic functionality introduced
by the above commit was under an #ifdef CONFIG_X86_64. Prior
to that we had a VM_BUG_ON(hstate_is_gigantic(h)).

--
Catalin