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Donenfeld" To: Linus Torvalds Cc: Andy Lutomirski , Ingo Molnar , 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 , Adhemerval Zanella Netto , Carlos O'Donell , Florian Weimer , Arnd Bergmann , Jann Horn , Christian Brauner , linux-mm@kvack.org Subject: Re: [PATCH v14 2/7] mm: add VM_DROPPABLE for designating always lazily freeable mappings Message-ID: References: <20230101162910.710293-1-Jason@zx2c4.com> <20230101162910.710293-3-Jason@zx2c4.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 1E6E44000F X-Stat-Signature: dybac3ookfzopxipz4oh63bqtre5wrz8 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1672778696-351203 X-HE-Meta: U2FsdGVkX18P2iyz2BY7DLSBb2UmrqZv1sgkM70jmdqiBPRCTV4PMJJxIaczLXDskYsrkgaE4r73jzQ4jqLYxaCsUg7iaTAO7MkCNCVGK+rTMsnoUA2EaPjtGqCmDySvouMjUdfgBMytIdTk6VfI0U5kacsU7so4fIomYiRExatVqCPMcCzLJ26ikZY7LmI7jIdjiwIbH7RHDFyXLODi0/+eJLxdRDkDGLVwbqY4ecTAJxI2qLOcZ4Ayp3Gligtx3No+urGMTd5N/Rn2hlUTgJN+ZSPXH2sbRRPFNgOxpmYfXRZKCI56isC5jSUd522fIXzpJFW9SAgxWgRIuhUCnrdrJOaFjc1FRcxC7ZhxFmx5EqVM+msezm60MqRHPhutgf52wHRC533Q3xzUe4BTMnGPqqBtDPcNfwH0yL0pN7HAsfnYAVKoxzgw1nlm9LxZXTMM2Exl9r6pTV3fJIe6tpMqyies+0a7VySBssBBt1C2ZatWV/PkTDaqfQNTct3OpQMhIyRpJ21qMZpHtOoxEayMHTM4cml5jEr/9xksfZkC5mJBhvaX2vlrdXOE4w7Af6QMB2cTVdwUEKVFU4G2floaxpJt9v/3VdhLTkDq+XSRNzGHsXuM7UdHT0sSVGUbEOXZlhbuAJ0QExapwvDFu3347yAx8TYxYSvxIkFl0GkTOwpxVirYVHO3x4FTaX7eNT1O65ks7j9m+w2EmO0GMjLU87wHP95fxOBpoR9FT6HmCJqEz9E3bQ1FeM5Y1uFjYEuLi45NIxmrIrY8f2byzGdhOqZJk1KOQPVP0NvstMBODBVluJ4EguUZv7KL+vvilK8OjFhaz3/5alPb7CYk9XIs94z/P3XhfALASft67xnAwouO/aKwYS2POZQOMKhtO0oI9pTDoVtcRMqj8qiUDIF4CZQAjd0+9gE+EF26QLuZPmhlqnCzJblyOzQlzHKzmLoKraAkLIqnK8X4q5d llQ4sbep pTES1DjsMEmZx47PYjHsLp6EYHRwpLfDPyCRvpoX2hrc2AKWXO3w8LdwsjC3+Th8vBhx7Y3eYb/FMoOa0S0QAq7/2cBM7ZDpQrKzcGrzHvnjClpPRx45SQlbl2acnxDxvVn03zdCq0PqL+kNnYkW9qezeme91GNUc6l28+cp2NoNXfz36fo3kZTrWfI+ktriOMuL87OmuN3UnsI0sPCMiOax9VDCqosE/EcqMA06qIAshwy/TNrWfji9Hv48sta+X8w3kKeWJMJBojS0= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 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