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Subject: Re: [PATCH v10 3/3] mm: add anonymous vma name refcounting
To:     Michal Hocko <mhocko@suse.com>, Kees Cook <keescook@chromium.org>
Cc:     Suren Baghdasaryan <surenb@google.com>,
        Pavel Machek <pavel@ucw.cz>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        David Hildenbrand <david@redhat.com>,
        John Hubbard <jhubbard@nvidia.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Colin Cross <ccross@google.com>,
        Sumit Semwal <sumit.semwal@linaro.org>,
        Matthew Wilcox <willy@infradead.org>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Randy Dunlap <rdunlap@infradead.org>,
        Kalesh Singh <kaleshsingh@google.com>,
        Peter Xu <peterx@redhat.com>, rppt@kernel.org,
        Peter Zijlstra <peterz@infradead.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        vincenzo.frascino@arm.com,
        =?UTF-8?B?Q2hpbndlbiBDaGFuZyAo5by16Yym5paHKQ==?= 
        <chinwen.chang@mediatek.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Jann Horn <jannh@google.com>, apopple@nvidia.com,
        Yu Zhao <yuzhao@google.com>, Will Deacon <will@kernel.org>,
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        Thomas Gleixner <tglx@linutronix.de>, krisman@collabora.com,
        Chris Hyser <chris.hyser@oracle.com>,
        Peter Collingbourne <pcc@google.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
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        Cyrill Gorcunov <gorcunov@gmail.com>,
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        Thomas Cedeno <thomascedeno@google.com>, sashal@kernel.org,
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        linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-mm <linux-mm@kvack.org>,
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Message-ID: <4a1dd04f-eda3-5c71-4772-726fd6fa2a38@intel.com>
Date:   Fri, 8 Oct 2021 07:14:58 -0700
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On 10/7/21 11:34 PM, Michal Hocko wrote:
>> Yes, please. It really seems like the folks that are interested in this
>> feature want strings. (I certainly do.)
> I am sorry but there were no strong arguments mentioned for strings so
> far.

The folks who want this have maintained an out-of-tree patch using
strings.  They've maintained it for the better part of a decade.  I
don't know how widely this shipped in the Android ecosystem, but I
suspect we're talking about billions of devices.  Right?

This is a feature that, if accepted into mainline, will get enabled and
used on billions of devices.  If we dumb this down to integers, it's not
100% clear that it _will_ get used.

That's a pretty strong argument in my book, even if the contributors
have difficulty articulating exactly why they want strings.