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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 3 Jan 2023 12:15:57 -0800
Message-ID: <CAHk-=wi4gshfKjbhEO_xZdVb9ztXf0iuv5kKhxtvAHf2HzTmng@mail.gmail.com>
Subject: Re: [PATCH v14 2/7] mm: add VM_DROPPABLE for designating always
 lazily freeable mappings
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     Andy Lutomirski <luto@kernel.org>, Ingo Molnar <mingo@kernel.org>,
        linux-kernel@vger.kernel.org, patches@lists.linux.dev,
        tglx@linutronix.de, linux-crypto@vger.kernel.org,
        linux-api@vger.kernel.org, x86@kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>,
        "Carlos O'Donell" <carlos@redhat.com>,
        Florian Weimer <fweimer@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>, Jann Horn <jannh@google.com>,
        Christian Brauner <brauner@kernel.org>, linux-mm@kvack.org
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On Tue, Jan 3, 2023 at 12:03 PM Jason A. Donenfeld <Jason@zx2c4.com> wrote:
>
> That buffering cannot be done safely currently

.. again, this is "your semantics" (the (b) in my humbug list), not
necessarily reality for anybody else.

I'm NAK'ing making invasive changes to the VM for something this
specialized. I really believe that the people who have this issue are
*so* few and far between that they can deal with the VM forking and
reseeding issues quite well on their own.

            Linus