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Thu, 19 Mar 2026 18:12:34 +0000 Received: from DS7PR12MB9473.namprd12.prod.outlook.com ([fe80::f01d:73d2:2dda:c7b2]) by DS7PR12MB9473.namprd12.prod.outlook.com ([fe80::f01d:73d2:2dda:c7b2%4]) with mapi id 15.20.9723.016; Thu, 19 Mar 2026 18:12:34 +0000 From: Zi Yan To: "David Hildenbrand (Arm)" Cc: Gregory Price , linux-kernel@vger.kernel.org, Catalin Marinas , Will Deacon , Huacai Chen , WANG Xuerui , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?LMHMUoNQ3MS3Q69v3mcA2Fkzm2TSYw6G+L1FAQc3D3kRr2xKGqWyGrYfuNsx?= =?us-ascii?Q?/FQvR+Fp/Tj92dmTFZvvaBa8k7Sj1QWzy+nDUXTGZj0eNQLtwVO/Hg6+WfqY?= =?us-ascii?Q?y9KQ57Nyw6m7m72oqewmJvR/aOnp/IA6zeRUiDmtGjSnk0v4QUQrIZcHMPzi?= =?us-ascii?Q?QwS9r5t+Z1JpHppIy+VbnskT1mnpY1av37vCB5XHNXiWnRMnxtYR/cGRGwlz?= =?us-ascii?Q?70i2pm8B/Q1FvIi3Ekj76Yg0SbUokY1PYx+Pzn+okrfX10GP4EbD6HMHGqq7?= =?us-ascii?Q?6ZZoW8lmxhImwdh69qzFCVasPHBiHlVctHO/euVAqaEjcvGaCI9aMMh/LJF+?= =?us-ascii?Q?9qtMlzonG8ZMnwEtoQHjG/qWn8ggIb3AfE8MB1j4ywsgfeuKnjJtBK6qFyJW?= =?us-ascii?Q?iNqv/ZQCV+PuBAvpv3svx7Yg736fR7wRguY1w+k1kroHZcKH2Wty/rpKjOs0?= =?us-ascii?Q?SjphdndhnJBH0LJt3io6nB5/j4jp21Skh93Yf4OsrNW6xlnpiP9Z/przoVZy?= =?us-ascii?Q?+c6Qz7hXiEbYgqDH9Mge0R2YgZY8cMxCFa+AekpIEnH3PYZKKIWodYYTwJee?= =?us-ascii?Q?NNh+t9ZF7QtavYSLasGXBSxhADWkOqtAOIHyLDMwIbzFMXW+gWZkfAexOxJG?= =?us-ascii?Q?Z+Zsseh4twR6FacyMvhN3XIgpMAWF94PeJqdqNdbeKR81TrP7qA77dPM0PJh?= =?us-ascii?Q?ks4ZxELf/lca5W8D7dFCv5r965FR10xh+Aans5C1DB2M/Gb2bxWWOQv4XtrF?= =?us-ascii?Q?HDnW1lV45VCVHS+s0qcPauSMrgFW6aNKIqQctYsEj6BQVy9tULl6Sn6xwCHd?= =?us-ascii?Q?RQVhdMmwPWnt7uzREmKG34sD2SifKExxp0OKdVN65kFdc4PeyTEF+FbzbOOX?= =?us-ascii?Q?iLFA3aUniuDLHFlj3JOgJ1UEgp+oWZNPiL9ej7cQKgljrF5TJQ9W3Wao9yEy?= =?us-ascii?Q?xDRTtVjXQYC/aBe6nBzK3MQmBcNU2Z5GnUA1T5TCRmE7OMJLTj8G6ai6riMZ?= =?us-ascii?Q?yJNyHb+YM6C3eesHIwo+M5wZQCS9vhtcAHxvnTdWwvGniWgmxLmd/YaPn2wA?= =?us-ascii?Q?fDukww5OPCl7hNjJ2wmb8KC5UNwVhbjc4z8BRlkfpr5mv5BtJCTeWSS9Cm5s?= =?us-ascii?Q?tGEvehINcj6Fj2hspZbX5jX+pUFRAADq5LZ31zeK7H5hA/WMJ3V0YnwsRKF8?= =?us-ascii?Q?OxpDZNLB6X+C8AZyPgWGU9H085Bn01EXUWDVOPMN6say2+s0P6tK4PT4Vyw9?= =?us-ascii?Q?A+0kTCfaXFYIWCBwB9BKsU6PADQwXtWOOvbOoMxCpAPwKciEiVO/MSWIxqZ3?= =?us-ascii?Q?E9heb8wY2mtDtYOa8xb2c/zG715kg3ubl36FmbVLiGtQqAr9VieBBA2wJ+9I?= =?us-ascii?Q?r2BmE346JPacQKxd87gZeV+KBBLEiJNoujrDxKrzB9GqAF3rU6RYt3s5NsUz?= =?us-ascii?Q?P6mvo/CA9TfBnkDcysDIsTTQFKuzvUwGQ653FUYaGo2R7miuKQl1A+fuWYgA?= =?us-ascii?Q?9QvTrAd/t0RoqYWhJoNC70rGO48YYPLFVDAss4jS4fdzqDXjQz979fbBCrRG?= =?us-ascii?Q?5Caw/VlKUfw/Spi63TUqkvcwF44TXRcQXrHiou7+rpqYkd3scCTcTv1FBsiI?= =?us-ascii?Q?UExnjr6vIQDXjPSihuFcuLNvM/HjWr+sJ6QbLfhMdMcPVNV1oqgC1NVstwxL?= =?us-ascii?Q?KuJjmUWT4mtvnx+/Pp7fbK2WtDgvYS8HFVB9PoMvItOFVHhyoc30yfCQ4lmn?= =?us-ascii?Q?Xu9k9eyqGw=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2914a4f3-c499-4769-2ec5-08de85e31810 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Mar 2026 18:12:34.3730 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: c34imI866VQA9+i3C2vgHyioo9/YTsvfsDoBfUr9ipUAYxxVWusAiwik46MAaWnI X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB7149 On 19 Mar 2026, at 14:08, David Hildenbrand (Arm) wrote: > On 3/19/26 16:24, Gregory Price wrote: >> On Thu, Mar 19, 2026 at 09:19:40AM +0100, David Hildenbrand (Arm) wrote: >>> All architectures that select CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE also >>> select CONFIG_ARCH_ENABLE_MEMORY_HOTPLUG. So we can just remove >>> CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE. >>> >>> For CONFIG_MIGRATION, make it depend on CONFIG_MEMORY_HOTREMOVE instead, >>> and make CONFIG_MEMORY_HOTREMOVE select CONFIG_MIGRATION (just like >>> CONFIG_CMA and CONFIG_COMPACTION already do). >>> >>> We'll clean up CONFIG_MIGRATION next. >>> >>> Signed-off-by: David Hildenbrand (Arm) >> >> HOTREMOVE has long been a thorn in my side, I appreciate you cleaning >> this up. > > On a long cardrive today I was wondering: do we still need a separate > MEMORY_HOTREMOVE You mean merge HOTREMOVE into HOTPLUG? I wondered the same. Is there a reason to only have HOTPLUG without HOTREMOVE? > > Now we'll have > > config MEMORY_HOTREMOVE > bool "Allow for memory hot remove" > select HAVE_BOOTMEM_INFO_NODE if (X86_64 || PPC64) > depends on MEMORY_HOTPLUG > select MIGRATION > > I'll try to get rid of that HAVE_BOOTMEM_INFO_NODE shite next. > > Then it's really just MIGRATION and some sprinkled > CONFIG_MEMORY_HOTREMOVE. Not a lot of code. Best Regards, Yan, Zi