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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?sTVrASoqMWE6eoDM5kL9rG/FsOg0YCJ17TOC+DSBJJqilkrVwY+kOQpMZNZE?= =?us-ascii?Q?e4nyLDxVZUptyqeSh9uCao+wy9HFupI74C80u6Kb8CKGXLa6qbhZAJZKc70H?= =?us-ascii?Q?DULZErqv76eAVmMfvE3Pl6qel78/p7JcvvU7/7UtGYYa8QBxeVBdGBd2yyzk?= =?us-ascii?Q?MPW1PSivzIaN+0VFYlUAc463y/N+owlexu5iBZwt794NoJQp5CN7JxdlkoAM?= =?us-ascii?Q?pKRdX8uFliKgwBjLslaRflwarrSR5vD9RKLJ8EImLNd9kPrmND2rUWigUBho?= =?us-ascii?Q?hSHgTls3BPO5EjtvqbxLClI1xg9BN3xWpX3AtCHQKKiArRkcGmRThPDWKron?= =?us-ascii?Q?PmgbpiZE35iMp6B1naMGvWaZnHos38/DxacQymXVaIWkyahpE8Ol9adYXj3Y?= =?us-ascii?Q?Slr3dS6hSHWBh4jRvHcRC/nQT/uW3VcAZasVA1mlFOcbiQh57NdNWHyQuVFe?= =?us-ascii?Q?/2F39X5H8wWXG0QvVtYiou4VEymgioM8GZoIYJIe+WtunRYD6QynvTZ8GAsb?= =?us-ascii?Q?hCH4oHA83TEHbhLlvdvytmODM/LNdm+N5OtXa8iy9VbvgtMa4ctMj5qcnL81?= =?us-ascii?Q?2sGVaD5CeDR3wMSdcdeXCGUsISxXPkgyeTj4x0kepOSAgc1l5Z9w8AGcg4dP?= =?us-ascii?Q?EPiKhl2lGkbb1LxQt4HdslmHXWR+t8J89h+aaksL9nQllCN9zSe8wTTz6LWa?= =?us-ascii?Q?tvT/zQzphwDFbKxNmm6FqqxywBu23Untz37FbrKdbr+AyD0ES0cFfYFFWhBy?= =?us-ascii?Q?r2d4W+hl8OCFgYzQ9Wj8omC2fwIclydUZKLG6Z85R8vqCH4B1bwNMKIJU6CO?= =?us-ascii?Q?Oy7YZECVIWKXY9GClBpQUbO3mJ9ER7UDiR2vmwx1T5CnQVVf7SQNvm7jFKZn?= =?us-ascii?Q?0l+3HjbNlAb0TGgdGRKQ5AmzzthV99EUe5RiUgmrmACy5CH+6sunAMdxCjxj?= =?us-ascii?Q?FX0Qh4t0rox4Ehz3eQIwOCoYqVirnnyWV+vxqpzud6gvbLp49z3FoamsPcpY?= =?us-ascii?Q?Ni9StWuHAr48au2y46emEopmU4pne5/5cJYULtnozc0lOJOsXMooe6Wm5/gs?= =?us-ascii?Q?yodtNMnGo/OqjcI9wBcPvzCAOyLpX2OYdK48YEQBpeX6s0XJcOKXEwbw7Ik2?= =?us-ascii?Q?Iyh76VQT7j5NDlczNoILUZIOFHDyKV2EbxGkt+qGJvGQSGKG1NvIUxJse4Yo?= =?us-ascii?Q?zTJqkumsRQz3ltw6GCikAcPNAsoeVmWGD3x6nNeXBsz29ILBHbjvxkaoVS8x?= =?us-ascii?Q?ynVp4nSgy8Z3yNV07He5ruEu7kXfh3aZ0tJNkdayQFHuuijp5DZrgeIp5YXs?= =?us-ascii?Q?rKHkPACvY+HEl+0O26VRDeI2PEkJOliDJTwjdvpM9C93K4T86EmVcumGxe1p?= =?us-ascii?Q?JAJDSUuuss4nbM8S/ChdWQe3YdSlWDYMlnx/+iaSdJZvqvZg1YblZ8WO2mop?= =?us-ascii?Q?vgT6Xjg3lnVlJZbXYmVZz1jtdsbazevFLT5AS6IgdYrsN6uNe7tUxKcudsG2?= =?us-ascii?Q?uJCNS40UADhT+yHkW5t3TYt9+ob1ObLwzK+UOgHt6H++r/yebjyox5YOmHQV?= =?us-ascii?Q?RVDO/ZiNnCGteHcGggnDaievmkpWSBOogcq/P0aB0K4vgPobbB2npJQNMGYE?= =?us-ascii?Q?SSOs7rArVEMlo0mYhk0uUHIMYwtXqkkcDy7/PJDP7gXH6vtBERuvQw89+aYA?= =?us-ascii?Q?S8T2f4BsgMw917aX7UEVe4Wol3pKnjxMuHJlIxg/EfPdSjCXxkdh0Xq6xlJS?= =?us-ascii?Q?w/h9eDoA5A=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 02b90373-1ad8-4215-7c1e-08ded7b30a7f X-MS-Exchange-CrossTenant-AuthSource: IA0PR12MB8374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Jul 2026 20:55:10.9853 (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: iA+e7aBFJSC0ccciZrwlWnZ6eY+ny9d2rfk/YWlYZVKCw+jeeFONb411BWthrCW5 X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL3PR12MB6379 On 1 Jul 2026, at 16:50, David Hildenbrand (Arm) wrote: > On 7/1/26 22:39, Zi Yan wrote: >> 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. > > hah! and 8 years later it seems to exist upstream :) > > commit 10dd5a0009898ba35eafeb6087e5c83b84742ff1 > Author: Gerald Schaefer > Date: Tue Jul 29 13:16:19 2025 +0200 > > s390/mm: Enable THP_SWAP and THP_MIGRATION > > After hugetlbfs PTE_MARKER support for s390 introduced region-third and > segment table swap entries, it is now possible to also enable THP_SWAP > and THP_MIGRATION for s390. > > So, with that out of the way, could you revive your patchset? > Sure. Will put that on my TODO list. Best Regards, Yan, Zi