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Howlett" , Vlastimil Babka , Jann Horn , Pedro Falcato , linux-fsdevel@vger.kernel.org Subject: Re: [RFC PATCH 3/6] mm: nommu: fix an issue on map request to /dev/zero Message-ID: References: <20260813063401.1786548-1-thehajime@gmail.com> <20260813063401.1786548-4-thehajime@gmail.com> <2026081355-remold-sterility-84f9@gregkh> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Queue-Id: F1A181C0005 X-Rspamd-Server: rspam07 X-Stat-Signature: dq9pzqpbp3m5u7sjwohwscurtgjhzur1 X-HE-Tag: 1786628616-481116 X-HE-Meta: U2FsdGVkX1+MTmdfQLw9MHeYBOD8GNjBbfbCT8pvNOUGuTgDu3Jvu0/qh2VMPMQDJVPAEftYgqn7NmK0qd2wk6hq2dHwrdyZ25ZoF6CweZqBq52hNcogYzquOroIpGaqqZkfMTAlqdNDN79pdqFRdAYIuZIgbRWdSKuv3emyc2KbPqxLXHUijW6uGb4Q1Bf6IIdZ4Onn0UtGlow6Gzofev47A3lA/DbXEFzuwDNvGRrIiZGKRoKDVUiC1PFGrXgSk7aFmeIKAf2ZspVZD4Q0IGOvZ5dy+zF3i4IP4moctj6oFIGhbXZ9yoFge2GSr8Np9zHlxNwRwICFIR3tswxSAbJ7/sjd4ZOap7+tntdsNElnh/0xvCrDt9BecRjUy5hSpfGYlJRwmElZZ7kws/qyFMWbNCTFlEp6yyp0lX9HCIzC5R83eF0WCzeDn4XXCDwNG4rKtD9r2hJgnLpnIyiPqU/rWT48yCGgjdFMWx2aKDcT6bg0soc0z4YukbozPfgYgWXcUhd/TZO8Uo8hrsmMO8TCwEYYdjfJcBqfx3/M1I9TUz9d7BCfmpnCd8u7Ht4iUSlMU4VD3hESM6QdJ+c8ROSLaG9ng5+eEL6ws2MMjdqPLPCNsEcd8h0pmXKBvzZfi4vSJ/Qf95JB3lBPomnZykJJ543tYcURhwUQ3SD2o0ThPUkv3lYRbuRQ7f7WFeO/D6tbc0oBWz+n6F4TMyyYwM7iWlv4r2FA1dN+YjPiDxlPjSkov1i47nPEfMhJI74VPXRZOfImHSoOBQR3cKM7jdHQkHJuMWWcgVQrd8bkn2pimg4QVreKWauw3QbyJWXuyvEholzI8aY2aQxvSLz9WvVQjQz6/D7JUqMbwtCBqtVT2wmwS/xZX/FHDAeZooGjGqkfsTzCw9X+DnUBI8BvPhNKn6MTMixty6xXauTHR4hADCr2bBgqA0uKDiBm7r1aErNS7/oFfjuDJI1ghkZ Iq87uLCh e01d8dkl1y+p0mDqUiHI6lAAhY8t7QBHB//Q5BQA5+L9Pl6rPOFKVbkVGgKBy5n/vMmI6y5QC1mUvMMvsk13T1u7GukLAwdr9pbiDHGpvBCZB6gY9vremyraxBCwcvfHwrafgq3GPkVn7myAwThp+jOdvDimwR3D8UdUIv0/yVUijylJRl+I/rEpROvA0kVa3PSPVkfQG7pWy45fXBuI9FUImADbzXy0ZWacxO2YG82Ep87Y/BYGci1kRysbzLGvQpppbA5wyogmia0I3r7dDxS3kfw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Aug 13, 2026 at 02:32:27PM +0100, Lorenzo Stoakes (ARM) wrote: > I do agree with Greg however that nommu is something we should get rid of. See > my other reply here. Sorry this was an overreach - Greg didn't say that :) I mean Greg asked if anybody uses nommu, the answer is yes, but the real question I think is 'is anybody using a very recent kernel who couldn't either use an older one or maintain a downstream kernel'. And to that I think the answer is absolutely not. And if the answer were yes - you must surely be a company with a product (security concerns on a nommu system is a debatable concept) - and then you need to put up or shut up IMO. -- Cheers, Lorenzo