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Date:   Tue, 3 Jan 2023 21:44:47 +0100
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>
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
Subject: Re: [PATCH v14 2/7] mm: add VM_DROPPABLE for designating always
 lazily freeable mappings
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On Tue, Jan 03, 2023 at 12:15:57PM -0800, Linus Torvalds wrote:
> 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.

Yea that's fair. Except, of course, I maintain that my semantics are
important ones. :)

> 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.

Okay, that's fine. I'll see if I can make this work without having to do
surgery on mm and introduce a new VM_* flag and such. Hopefully I'll
succeed there.

Jason