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Fri, 14 Apr 2023 08:41:14 +0000 (GMT) Received: from epsmgms1p2.samsung.com (unknown [182.195.42.42]) by epsmtrp1.samsung.com (KnoxPortal) with ESMTP id 20230414084114epsmtrp12c1bc90e6d21d3f326abd82aca17651b~VwHwGZMyk2509225092epsmtrp1Z; Fri, 14 Apr 2023 08:41:14 +0000 (GMT) X-AuditID: b6c32a48-5dcdca80000025b2-37-643911ab1f66 Received: from epsmtip1.samsung.com ( [182.195.34.30]) by epsmgms1p2.samsung.com (Symantec Messaging Gateway) with SMTP id 13.7D.08609.AA119346; Fri, 14 Apr 2023 17:41:14 +0900 (KST) Received: from dell-Precision-7920-Tower.dsn.sec.samsung.com (unknown [10.229.83.99]) by epsmtip1.samsung.com (KnoxPortal) with ESMTPA id 20230414084114epsmtip165afde30d3f8bdb70e97963eb0ad423d~VwHv6UUU43026630266epsmtip1Z; Fri, 14 Apr 2023 08:41:14 +0000 (GMT) From: Kyungsan Kim To: willy@infradead.org Cc: lsf-pc@lists.linux-foundation.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-cxl@vger.kernel.org, a.manzanares@samsung.com, viacheslav.dubeyko@bytedance.com, dan.j.williams@intel.com, seungjun.ha@samsung.com, wj28.lee@samsung.com, hj96.nam@samsung.com Subject: RE: RE: FW: [LSF/MM/BPF TOPIC] BoF VM live migration over CXL memory Date: Fri, 14 Apr 2023 17:41:14 +0900 Message-Id: <20230414084114.440749-1-ks0204.kim@samsung.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrBJsWRmVeSWpSXmKPExsWy7bCmue5qQcsUg0VTuSymH1a0mD71AqPF hzf/WCzOzzrFYrFn70kWi3tr/rNa7Hu9l9niRedxJouODW8YLX7/mMNmsfH+OzYHbo9/J9aw eWxeoeWxeM9LJo9Nnyaxe0y+sZzRo2/LKkaPz5vkAtijsm0yUhNTUosUUvOS81My89JtlbyD 453jTc0MDHUNLS3MlRTyEnNTbZVcfAJ03TJzgE5UUihLzCkFCgUkFhcr6dvZFOWXlqQqZOQX l9gqpRak5BSYF+gVJ+YWl+al6+WlllgZGhgYmQIVJmRnLOi+y1wwW7ji98YbbA2Mn/m7GDk5 JARMJJ713mLtYuTiEBLYwSjxbnEnlPOJUeL1mXMsEM5nRokzax+zwLScX3OKGSKxi1Giddky KKeLSWLK/SvsIFVsAtoSf66cZwOxRQTEJY5NPckIUsQsMI1JYtHWs2AJYYEAid5Z3xlBbBYB VYl7d1cyg9i8AjYSU3f+gVonLzHz0newoZxAq1dOncsIUSMocXLmE7AaZqCa5q2zwa6QEJjI IfHn83EmiGYXiS8Td0MNEpZ4dXwLO4QtJfGyvw3KLpZ4/PoflF0icXjJb6h6Y4l3N58DQ4MD aIGmxPpd+iCmhICyxJFbUGv5JDoO/2WHCPNKdLQJQTSqSGz/t5wZZtHp/ZughntI7Fo2H+xz IYF2Rom7l9UnMCrMQvLMLCTPzELYu4CReRWjWGpBcW56arFRgQk8hpPzczcxgpOslscOxtlv P+gdYmTiYDzEKMHBrCTC+8PFNEWINyWxsiq1KD++qDQntfgQoykwqCcyS4km5wPTfF5JvKGJ pYGJmZmhuZGpgbmSOO/HDuUUIYH0xJLU7NTUgtQimD4mDk6pBiaDsx/KwvoK4g2CfK1qc51X /Wg4EX2qx75IbceUaSovL5oImxge3HLho2X3mjfRXYZ1S6bfWrFuLdulKVfZrj7b2PimqGH9 npqkPr3rJvNn104RDDop+nX37IUxi18bPJ/2reX8wpu8t/lcTSO8WkVX3W9K2SS4/XTwRKct hxfdtrnb4+Qq6R/f4/vg1fPJee+XiDFHvhNjSHr+501i28etL3QafjrKnT7L+l9Pts7FJ2fj h38uvAe32MsnnlW76eJ3O+mZcXeh1rQfLr2Ne2S+Vn/5Jx9ZGHHv5ermP6tD2oU/l3bqvbw7 ad+PsD//Jn8WcWKZx/xq7zRFpd/ryhpOmiXExTh4/Fln8epTgdg3JZbijERDLeai4kQA8h4j ODsEAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrMLMWRmVeSWpSXmKPExsWy7bCSnO4qQcsUg1VTdCymH1a0mD71AqPF hzf/WCzOzzrFYrFn70kWi3tr/rNa7Hu9l9niRedxJouODW8YLX7/mMNmsfH+OzYHbo9/J9aw eWxeoeWxeM9LJo9Nnyaxe0y+sZzRo2/LKkaPz5vkAtijuGxSUnMyy1KL9O0SuDIWdN9lLpgt XPF74w22BsbP/F2MnBwSAiYS59ecYu5i5OIQEtjBKLFv61oWiISUxPvTbewQtrDE/ZYjrBBF HUwS6w4vBStiE9CW+HPlPBuILSIgLnFs6klGkCJmgQVMEhtnrAEay8EhLOAnMXdrBkgNi4Cq xL27K5lBbF4BG4mpO/9ALZOXmHnpO9gyTqCLVk6dywhiCwkYS1xvg6kXlDg58wlYPTNQffPW 2cwTGAVmIUnNQpJawMi0ilEytaA4Nz232LDAKC+1XK84Mbe4NC9dLzk/dxMjOB60tHYw7ln1 Qe8QIxMH4yFGCQ5mJRHeHy6mKUK8KYmVValF+fFFpTmpxYcYpTlYlMR5L3SdjBcSSE8sSc1O TS1ILYLJMnFwSjUwTVomMH2NJZss95976zy87f8wzuIQEp3DvP74/3k1lVLlz3KvOZ8J9L+y /mfPL2/90vsGtqvVRfYZ6K8x9vfI72WRt7pz+CGHT/af/7EhCj852SKXXxS19A6cPcO70XCv t+66/zIBvCEp0TxzSlTS98z+v+RUEe8hqTk8U8OO3VlZG3kpYlbam4Dq5x3Td/m8efuke/r6 J2tyIktWWl56uUNDoG+/ulypzDMfnsx3DUHX9gQeOaq7K2cK68sfa7wnVRd9efWpoCfyvvLZ dT1uHvpr2Ts3mEx9N2ljj9pmOfVFLQ+rE6rY5eZ9O3trxVrJuG8330/InuWt/PHJ4cfyL8sZ hPrf3O9nTi4u+nK6RImlOCPRUIu5qDgRAADVR6b2AgAA X-CMS-MailID: 20230414084114epcas2p4754d6c0d3c86a0d6d4e855058562100f X-Msg-Generator: CA Content-Type: text/plain; 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Tell us what >your requirements are, at a really high level, then walk us through >why ZONE_EXMEM is the best way to satisfy those requirements. Thank you for your advice. It makes sense. We will restate requirements(usecases and issues) rather than our solution aspect. A sympathy about the requirements should come first at the moment. Hope we gradually reach up a consensus. >Also, those slides are terrible. Even at 200% zoom, the text is tiny. > >There is no MAP_NORMAL argument to mmap(), there are no GFP flags to >sys_mmap() and calling mmap() does not typically cause alloc_page() to >be called. I'm not sure that putting your thoughts onto slides is >making them any better organised. I'm sorry for your inconvenience. Explaining the version of document, the 1st slide shows SMDK kernel, not vanilla kernel. Especially, the slide is geared to highlight the flow of the new user/kernel API to implicitly/explicitly access DIMM DRAM or CXL DRAM to help understanding at previous discussion context. We added MAP_NORMAL/MAP_EXMEM on mmap()/sys_mmap(), GFP_EXMEM/GFP_NORMAL on alloc_pages(). If you mean COW, please assume the mmap() is called with MAP_POPULATE flag. We wanted to draw it simple to highlight the purpose. The document is not final version, we will apply your comment while preparing.