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Date:   Mon, 11 Dec 2023 12:29:58 -0800
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Subject: Re: [PATCH v6 5/5] selftests/mm: add UFFDIO_MOVE ioctl test
Content-Language: en-US
To:     Mark Brown <broonie@kernel.org>
Cc:     David Hildenbrand <david@redhat.com>,
        Suren Baghdasaryan <surenb@google.com>,
        akpm@linux-foundation.org, viro@zeniv.linux.org.uk,
        brauner@kernel.org, shuah@kernel.org, aarcange@redhat.com,
        lokeshgidra@google.com, peterx@redhat.com, ryan.roberts@arm.com,
        hughd@google.com, mhocko@suse.com, axelrasmussen@google.com,
        rppt@kernel.org, willy@infradead.org, Liam.Howlett@oracle.com,
        jannh@google.com, zhangpeng362@huawei.com, bgeffon@google.com,
        kaleshsingh@google.com, ngeoffray@google.com, jdduke@google.com,
        linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
        kernel-team@android.com, Peter Zijlstra <peterz@infradead.org>
References: <20231206103702.3873743-6-surenb@google.com>
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 <3eadd79c-c02a-495f-92c0-0315046ef59f@nvidia.com>
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From:   John Hubbard <jhubbard@nvidia.com>
In-Reply-To: <3d22f342-280f-4a44-87f4-8cca291cfce7@sirena.org.uk>
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On 12/11/23 12:21, Mark Brown wrote:
> On Mon, Dec 11, 2023 at 10:46:23AM -0800, John Hubbard wrote:
> 
>> Or (4) Hack in little ifdef snippets, into the selftests, like we used
>> to do. Peter Zijlstra seems to be asking for this, if I understand his
>> (much) earlier comments about this.
> 
> I can't help but think that if we're having to manually copy bits of
> the uapi headers (which are already separated out in the source) into
> another part of the same source tree in order to use them then there's
> room for improvement somewhere.  TBH it also doesn't seem great to add

Yes, it feels that way to me, too.

> additional variables that depend on the user's build environment, we
> already have enough build issues.  It ought to be mostly tedious rather
> than hard but it's still a pain, especially given the issues we have
> getting kselftest fixes merged promptly.

What about David's option (3):

(3) Regularly archive the required headers in the selftest directory
     like external projects like QEMU do.

, combined with something in the build system to connect it up for
building the selftests?

Or maybe there is an innovative way to do all of this, that we have
yet to think of.


thanks,
-- 
John Hubbard
NVIDIA