Re: [PATCH] mm/mmu_notifier: fix mmu_notifier_range_init warning

From: Arnd Bergmann
Date: Tue Dec 11 2018 - 16:53:23 EST

On Tue, Dec 11, 2018 at 10:43 PM David Rientjes <rientjes@xxxxxxxxxx> wrote:
> On Tue, 11 Dec 2018, Jerome Glisse wrote:

> Hmm, strange that Arnd's build failure is only reporting about an unused
> variable instead of MMU_NOTIFY_CLEAR being undefined :/
> I think this should be done so that anybody using
> mmu_notifier_range_init() doesn't need to worry about the implications of
> *any* unused formal parameter as a result of how the #define is formed:

Your patch below is more or less what I tried at first, and that resulted
in another build failure for

mm/hugetlb.c: mmu_notifier_range_init(&range, mm, start, end,
mm/hugetlb.c- adjust_range_if_pmd_sharing_possible(vma,
&range.start, &range.end);

where range.end refers to a nonexisting member of range.