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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?xD8IoMDK7u3DRrEq2lbtEaTZCH7Jw8n8y+9T2TlVKWjdZ1+nFmC9cvw/qNYd?= =?us-ascii?Q?ngGnBoRXU/pLqfJypK5PLk9HnaboL02anLKrmTWYRdhEUOLmjSKRBbPAAYRP?= =?us-ascii?Q?XSb87tZKAWUbjIImvsJN0ymsNACAmEPbMUp/5Sy8axSqv13UrjJfSPgQsJ9u?= =?us-ascii?Q?3RD6cfEXqXqdQx3w7iD9bHaQtTqPd+DSK5DpXbpIW1e5Su4fu/X5Gez+/xca?= =?us-ascii?Q?TBGqIPAisTSurnSEjPsaBK67Fyy0AQKmmSgRtlE610/4SfWpaWQMF2M/dcd8?= =?us-ascii?Q?5h1/I5zfWqapmHb6xPV6TvvI81VlsNBO64YFMKyVeyulX6epFUZXAVkWH5rt?= =?us-ascii?Q?av4rJaKRf/rbFGXJA6LyNvfGJAlNqVvFvpoDtndmG2p7Pv2iXbK5PTNBbeu3?= =?us-ascii?Q?OejLDLCXSaFVsfAUqeCx2Mg/e0wQm9bXthozdR567wBJcqUsytXC3ndw+yu9?= =?us-ascii?Q?5oTYaRCUbW8brCPJyzkSzEQOr4jOlxpNZw811fi9pZdl0gf+8Vp5ujTZkEAE?= =?us-ascii?Q?0DOY7DPky2dAv3zr+BmMmwSSNdIm7/eG0db/wF6eRgiKeeKbznCzslAVzWa4?= =?us-ascii?Q?CTbbDQ7XUp4pIGdLtQWtymhDTOuyRiE5ym0jMwmLsXeW9jys76YXX8zFI4oo?= =?us-ascii?Q?ZtPJgjbtBnXr/Yuayb3pAclfnfs6NA8dKwseQwgbIuwRXhsKMrmiDudXsAlk?= =?us-ascii?Q?i3zxICCCQSlSQBu8k1xDS1UgwoVscaWluvYb/GslCpkhkJVJpL8OIHrcMOal?= =?us-ascii?Q?wiejCovfM0ywIDLWcA8iQLpVj8iUk+NJ2MtHGU+/GhHBnwidS+DQCQCUy2Yr?= =?us-ascii?Q?pp0Yhl1FitsdxpmEB+pNP8RuYyGOEW7+yisGZTYPHdHcVkiMFfhSb0zOtLep?= =?us-ascii?Q?cRWPSiHZteGpP1KywOSHAXTZoR+eN4jMmQcQVUJYoLgje/T9FRWaAPnMilK1?= =?us-ascii?Q?odq32qKP07ULuKjToylwZo99xBamYJ06C47HSNGsu6cIwlWIvs5C5/mAkeNV?= =?us-ascii?Q?vfym7l10yfWlvHf64je7XFXsIXWHTus7d1+gNHsUO1vAmnaVbvgykdVnIImr?= =?us-ascii?Q?FGNscIxo1aYmrACj2gHJFbc1gzLefnAq+p6UdTKAwVuQzWMjnnarbAAlGRNF?= =?us-ascii?Q?aZbPcqqG8+3kEJyuUBexvPU5+IqbXgwJzi8v9JHsoF3DCkY3Nmt9GKOb0f1I?= =?us-ascii?Q?Z25H6VXUIhqD/Zaw1QO7qfqQRjKz7iqWPYmRwZ8C6ro27rMDT0qgNTiTycQS?= =?us-ascii?Q?gnSM2dNS2CA8Z4zDLXamFPS8fLhN5BWHrIOlzGVxDvkC3GZtncP82wAokBBv?= =?us-ascii?Q?xdh4fsBeX18ce/4QdDoj/ybWEqrGZLV9+WAKcm3u0c3WupfIcWJTJysuH3Et?= =?us-ascii?Q?MNaiG0LxOdbIBO3oDnKleJ+j1lumazuEZtTlEHi34et7CJzyHLSkyBhvZmd1?= =?us-ascii?Q?6nBTZxNC3SmhHrRA/C2zRRDwUEdMUvXenQ/izLxmMXxJLMtvxoAj/aEldZ5J?= =?us-ascii?Q?wmErzRpg/fYdEMRDfzaI5ZjYuG2p/eNT95nCPtxoIU6yenEgyQo8FPuAHUfw?= =?us-ascii?Q?mQMRfiwydsXoU7XLQlyABtL2BrQqYEEQok/Ig+vh2uVRPlp9U4jqO+9i/K6V?= =?us-ascii?Q?99iQoK5s3riw035NRn14znRfoV94LOZMbAF52AEOqtGN3AqqbdefUUr1JGjh?= =?us-ascii?Q?hmGs55Z0AHoNYUYkfIU9Po8wDvr+Vwnzda227OQ99jflDSgFNYpYpSF1Rwj7?= =?us-ascii?Q?9JqtjvVlzQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: bff7380c-d87f-44f6-482a-08ded7b0d2ec X-MS-Exchange-CrossTenant-AuthSource: IA0PR12MB8374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Jul 2026 20:39:18.7575 (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: 6O4Xh4iAyFAhO3XLDhjR7CCrbXsUS/cBTjWESlpdszS6IyjnSPqSY1vcn17lKqIE X-MS-Exchange-Transport-CrossTenantHeadersStamped: PHXPR12MB999255 On 1 Jul 2026, at 16:03, David Hildenbrand (Arm) wrote: > On 6/30/26 18:34, Usama Arif wrote: >> CONFIG_ARCH_ENABLE_THP_MIGRATION started life gating just PMD-level >> migration entries, but has grown to gate the entire PMD-level softleaf >> machinery: migration entries, device-private entries, and soon swap >> entries. > > device-private really relies on migration support. > > See do_huge_pmd_device_private() where we migrate back to CPU memory. > > The whole concept is pased on migration. So that's why it currently makes sense. > > So "has grown to" is not quite accurate. It's a different story with swap > entries (that can exist even without migration support). > > >> Rename CONFIG_ARCH_ENABLE_THP_MIGRATION to CONFIG_ARCH_SUPPORTS_PMD >> _SOFTLEAF to make this clear. This is a pure rename: the set of >> selecting architectures (x86, arm64, s390, riscv, loongarch, and >> powerpc on PPC_BOOK3S_64) and the gating semantics are unchanged. > > Hm, that makes me wonder what it would take to make this all just be implicitly > supported by CONFIG_TRANSPARENT_HUGEPAGE. > > Looks like someone would have the courage to touch stuff like arc, mips and > sparc64 (+arm and x86, but that's less of a concern :) ). You mean me back in 2018[1]? ;) At least I got a no go for s390. [1] https://lore.kernel.org/linux-mm/20180426142804.180152-1-zi.yan@sent.com/ Best Regards, Yan, Zi