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Fri, 27 Feb 2026 10:36:34 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id awcFALJzoWnFbwAAD6G6ig (envelope-from ); Fri, 27 Feb 2026 10:36:33 +0000 Date: Fri, 27 Feb 2026 10:36:32 +0000 From: Pedro Falcato To: anthony.yznaga@oracle.com Cc: lsf-pc@lists.linux-foundation.org, linux-mm@kvack.org Subject: Re: [LSF/MM/BPF TOPIC] mshare - sharing page tables across processes Message-ID: <6dfb6mndousbfpsaa5ndcytjcpdnixo6yczjduogs6f7kb4ewr@zx23tvriuj2z> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 0F479A000C X-Stat-Signature: r6ir7nogepxrcjrkxi4nhs17xhzz76dw X-HE-Tag: 1772188595-332391 X-HE-Meta: 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 cQ1BLxUP n6HuQuMkyUFx00v3Oj0jeb440AbB+WCpYqNA/fEYgeXQWkvB9hnAnbYuv36tsxrzSM+kr/luQpwQ6mN7iG8OaRvoC31MHPJWpXkSk4ZSK4xlx77Bb3o//NdIeZ6QUlf2pGwdrAwFH6FUpJuMVek48ApIiwKKenuujjsHVJnn91ihyIzGTVd5Cbnc3gcrwfmYpBGK4BPLnaXC6a6J/IbH4DeE/tvwCEKn5qaUmhHUmX6+cftYIQE1U90Q3MpQ8gYF0yaRWQ/2GUgsJmzT73UAISbM9tD1H4iGM0DyUb7/07sFBVkghV/NFIIBz5Y1w2CYE2XvP Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Feb 23, 2026 at 06:11:49PM -0800, anthony.yznaga@oracle.com wrote: > mshare is a new form of shared memory that shares resources between > processes, namely the page tables entries and VMAs of the shared objects. > Advantages include reduced memory consumption through eliminating the need > for duplicated PTEs in each process, reduced overhead needed to fault shared > pages into multiple processes, and the ability for updates to the memory > such as protection changes to be immdediately visible to all sharing > processes. > > For some time now the proposed API has continued to evolve. With feedback > from mm maintainers, a new approach using syscalls is being taken to create, > attach, and deattach mshare regions and to map and manipulate the memory > objects within a region. > > Let's discuss the current state of the API and technical challenges of > managing and accomodating shared page tables in the kernel. > Hi Anthony, As always, would love to talk about this in person :) -- Pedro