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Message-ID: <1156ad46-1952-4892-8092-bfbb8588c3f3@redhat.com>
Date:   Mon, 23 Oct 2023 14:03:15 +0200
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Subject: Re: [PATCH v3 2/3] userfaultfd: UFFDIO_MOVE uABI
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To:     Peter Xu <peterx@redhat.com>
Cc:     Suren Baghdasaryan <surenb@google.com>,
        Lokesh Gidra <lokeshgidra@google.com>,
        akpm@linux-foundation.org, viro@zeniv.linux.org.uk,
        brauner@kernel.org, shuah@kernel.org, aarcange@redhat.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
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From:   David Hildenbrand <david@redhat.com>
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On 22.10.23 17:46, Peter Xu wrote:
> On Fri, Oct 20, 2023 at 07:16:19PM +0200, David Hildenbrand wrote:
>> These are rather the vibes I'm getting from Peter. "Why rename it, could
>> confuse people because the original patches are old", "Why exclude it if it
>> has been included in the original patches". Not the kind of reasoning I can
>> relate to when it comes to upstreaming some patches.
> 
> You can't blame anyone if you misunderstood and biased the question.
> 
> The first question is definitely valid, even until now.  You guys still
> prefer to rename it, which I'm totally fine with.
> 
> The 2nd question is wrong from your interpretation.  That's not my point,
> at least not starting from a few replies already.  What I was asking for is
> why such page movement between mm is dangerous.  I don't think I get solid
> answers even until now.
> 
> Noticing "memcg is missing" is not an argument for "cross-mm is dangerous",
> it's a review comment.  Suren can address that.
> 
> You'll propose a new feature that may tag an mm is not an argument either,
> if it's not merged yet.  We can also address that depending on what it is,
> also on which lands earlier.
> 
> It'll be good to discuss these details even in a single-mm support.  Anyone
> would like to add that can already refer to discussion in this thread.
> 
> I hope I'm clear.
> 

I said everything I had to say, go read what I wrote.

-- 
Cheers,

David / dhildenb