Message-ID: <460b50d3-579c-5dfa-7c1b-531cc9b1c2d5@redhat.com>
Date:   Mon, 20 Mar 2023 16:01:39 +0100
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Subject: Re: [PATCH v4 2/2] selftests/mm: Smoke test
 UFFD_FEATURE_WP_UNPOPULATED
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To:     Peter Xu <peterx@redhat.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Nadav Amit <nadav.amit@gmail.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Paul Gofman <pgofman@codeweavers.com>,
        Muhammad Usama Anjum <usama.anjum@collabora.com>,
        Mike Rapoport <rppt@linux.vnet.ibm.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>
References: <20230309223711.823547-1-peterx@redhat.com>
 <20230309223711.823547-3-peterx@redhat.com>
 <4ab36009-51c0-6583-4948-b267f8fbf32a@redhat.com> <ZBhxLOBocC7mCYDG@x1n>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <ZBhxLOBocC7mCYDG@x1n>
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On 20.03.23 15:43, Peter Xu wrote:
> On Mon, Mar 20, 2023 at 11:25:43AM +0100, David Hildenbrand wrote:
>> On 09.03.23 23:37, Peter Xu wrote:
>>> Enable it by default on the stress test, and add some smoke tests for the
>>> pte markers on anonymous.
>>
>> Would it make sense to make kernel support optional and test both paths --
>> once with the feature enabled (if available on the kernel we're testing) and
>> once with the feature disabled?
> 
> Yeah, I think the current uffd selftest is not friendly to old kernels so I
> made it simple - IOW the test should fail already on old kernels AFAIK.
> Maybe I can prepare some patches this week or next to cleanup some parts of
> it.

Some people to tend to run upstream selftests on older kernels, but I 
guess this is not high priority. Can always be added on top.

-- 
Thanks,

David / dhildenb