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Date:   Fri, 2 Jun 2023 17:43:19 -0700
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Subject: Re: [PATCH 10/12] selftests/mm: move uffd* routines from vm_util.c to
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From:   John Hubbard <jhubbard@nvidia.com>
To:     Peter Xu <peterx@redhat.com>
CC:     Andrew Morton <akpm@linux-foundation.org>,
        David Hildenbrand <david@redhat.com>,
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On 6/2/23 15:52, John Hubbard wrote:
> On 6/2/23 15:38, Peter Xu wrote:
> ...
>>> I think we're in agreement that we want to only include uffd-common.h
>>> where it's actually required. Likewise with the uffd*() routines. So I
>>> would like to still move this over, yes, just to have things in their
>>> best-named location.
>>
>> Sorry I didn't get it - e.g. I'm confused why we need to export
>> uffd_test_ops into ksm unit test, it doesn't make much sense to me..
> 
> Oh, I see what you mean, finally. Yes. ksm should not need that.
> 

...whoops, correction, our very own David Hildenbrand recently made
changes that contradict the claim that "ksm and uffd selftests are
independent". In fact, ksm now *intentionally* depends upon uffd, as of
commit 93fb70aa5904c ("selftests/vm: add KSM unmerge tests"), aha!

That added commit added a call to test_unmerge_uffd_wp(), to
ksm_functional_tests.c .

So this needs to stay approximately as-is, it seems.


thanks,
-- 
John Hubbard
NVIDIA