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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?CHfPBgBpR4JRZHcnH3BU/sTQQGCTPBF2MjrfJPj/cCPuVs+dhHHSbwxz/Xds?= =?us-ascii?Q?6wviDKWRjM3X0Rjteh5Zsl+J3R9gO3xmwWsvVLy8eptG4ZnQbr4YQcozUJ/P?= =?us-ascii?Q?KxAvarycpVT1duCwg1b/Kgfu5JP7o+vsOxhWCIMDGeoYh/cKo9nIitI73Jvy?= =?us-ascii?Q?VXYXv8UEVZtTlFmWXHXhwaRSWoJcntHHbpMy/1U64SU0qs34RCZsyV6N6CGT?= =?us-ascii?Q?k8jC57ebv0GG8gHX3Hdm+XGbgT+MdctrvVKkF9cdGYToOxsjLt8tbFOsJKqX?= =?us-ascii?Q?94Om1YwJRBHvXMyhhtJnji7wYZOqpH4rtwsLe/elK+4fUN+CAEkN8GGl+NUf?= =?us-ascii?Q?/jvWzfWqXQfS8d4a7bh9WpmJi8Y1a3xXgrs7yGMC1JYLEHM1OirVvVIKMgPI?= =?us-ascii?Q?LiN0nhIodn1QRSJEZ/9VbLwJql69waLwoCa9ocXTuGOrawid95AFon/Ki/L6?= =?us-ascii?Q?f0wotOGltCHUegcWm7uTmaMFe4H5eWI8n+4BFu5MH0s1qzVu4ZIpyNM0Demj?= =?us-ascii?Q?Rnaa/qqPGLsEkrjMnY3N/8uRsoIcLvYMWryNMqlzqijIzsN0fLshbCGDQ4b4?= =?us-ascii?Q?L7VdDYKu5pTSYsra33JwIrP9NakeD98icLKGM7M1FA3oCB/fAMdV6Ga1Di+5?= =?us-ascii?Q?isfxRamp3pfHrCZGYoKG0HNx4jo0Dii8GPWFs5KR7hK8MXs8+ffsIld+K8zB?= =?us-ascii?Q?wW3I9lGjVOnvSD2QCCJJObPn+94J7Bn48sNAvNk81RLnGcGF1M0ObbCsItsb?= =?us-ascii?Q?6CkDBlIpKAhY00ox294GO3AkB77DdnHYSXP5recowFjULyZvPtWUrEcmRQy4?= =?us-ascii?Q?RG+Ct6goilnDrUsFcDcrtPS5dFrYgFuHNQ93r8sFRmSlIzDt3ubrBz9FV0zc?= =?us-ascii?Q?51VUAZg3voK263YKlM156VuVKbuw3+jXbU0qpjSwGKayy8YkaD73/mXV9FX4?= =?us-ascii?Q?tmJ0UWA/J5nt5hyvkt6r9HZyb1IeofN/GAgeX9vrORxWDrZ+K9Ex7pftHIwU?= =?us-ascii?Q?xFVLtcWaszFOS7cdR6s8wbAUyy/+sqYExCj5qFf8fd4BX1vMB6HR/hXTc5LG?= =?us-ascii?Q?2DLP/LMpsUCZdWnpPcTYsnQNZ+zOBLM+FMjFJfFYZdDnTjjpizFcmwx5JXDg?= =?us-ascii?Q?ZEqdotLAzBt74XsHISSC+Vc00sV9/9wwNvnyBe/plsBGnGjXaJyqz0IAFkR4?= =?us-ascii?Q?D320xXNOE5+ehwesfRvJED4Ij7tKjbqI+BVfkb4mAxDriH4gJuXbHg8kE8kV?= =?us-ascii?Q?3kNfns6xs5y9iDIf5UDPFWcX2PldSuw4HmTf8MPUieLPUuqpsRtD+6R1Tmac?= =?us-ascii?Q?IrzWWJMQ9NWk052KcFERrMHuY4zUiW6lDZen8ndVIFfeYdNgWpXdjoOtz1vf?= =?us-ascii?Q?4MfXAZI/YAC3vX24Q1STmsyHg6XftusGskpQV2HU58t0EKsJ2KKYnrbZRprm?= =?us-ascii?Q?E6KujXHy6R0qh38ICAigV8VragTQAZAXYLdbIFW810656yZfpg12PxSOmmya?= =?us-ascii?Q?upkv/Q6l7lMZwbVZd0gJq3S728FnvyUB1o7ySDOvmeM0U611oRWnEMiKJeCz?= =?us-ascii?Q?8ti6jlN1bMUq5wuHe1aHnYEw2Gr8ifyslRcoq9Ywv1ky1v577KnKzgJR2ihs?= =?us-ascii?Q?OTS8Yf3bJM5+tix2Hvo89sm82JwJXSlTX01DJlWRn1rebWdnhm6ldvGVsw1p?= =?us-ascii?Q?5T7DhVWyvrnWOIU9oMCkVurV1sptF5jvM+YAkmt9ob0eqopv?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 738c665a-7cea-4b24-3e9d-08df1395c264 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB8371.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Sep 2026 01:56:44.4498 (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: z5v3GYPwjeqWseymVVEoyEgBswm/qYrvwkhRmWSVc4ca/9qOTmVM2Ks8orTqynHG X-MS-Exchange-Transport-CrossTenantHeadersStamped: DSVPR12MB999308 On 13 Sep 2026, at 22:24, Zi Yan wrote: > folio_change_private() should be used along with folio_attach_private() and > folio_detach_private(), where adding and remove ->private content requires > folio refcount change. add_hugetlb_folio() simply sets folio->private to > NULL without refcount manipulation. Change it to direct assignment to avoid > semantic confusion. > > It prepares for a future commit that remove PG_private. > > No functional change intended. > > Assisted-by: LLM > To: Muchun Song > To: Oscar Salvador > To: Andrew Morton > Cc: David Hildenbrand > Cc: linux-mm@kvack.org > Cc: linux-kernel@vger.kernel.org > Acked-by: Usama Arif > Reviewed-by: Gregory Price (Meta) > Signed-off-by: Zi Yan > --- > mm/hugetlb.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index d3a0650ff6905..8d551cdaef9db 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1446,11 +1446,8 @@ void add_hugetlb_folio(struct hstate *h, struct folio *folio, > } > > __folio_set_hugetlb(folio); > - folio_change_private(folio, NULL); > - /* > - * We have to set hugetlb_vmemmap_optimized again as above > - * folio_change_private(folio, NULL) cleared it. > - */ > + /* Clear all folio->private flags except hugetlb_vmemmap_optimized. */ > + folio->private = NULL; > folio_set_hugetlb_vmemmap_optimized(folio); > Sashiko[1] said when a CMA hugetlb folio is freed but fails vmemmap restore, add_hugetlb_folio() clears HPG_cma. It either bypasses hugetlb_cma_free_frozen_folio() due to the missing HPG_cma flag, or skips cma_release() and causes a CMA memory leak if it is free directly to buddy allocator. Sashiko also asked if HPG_temporary should be preserved as well HPG_cma. Answer: Missing HPG_cma is a real issue. It can be fixed by checking folio_test_hugetlb_cma(folio) at the beginning of add_hugetlb_folio() and setting HPG_cma after folio->private is assigned to NULL. HPG_temporary does not need to be preserved, since the folio is added back to the surplus pool. I will send a patch to fix the missing HPG_cma with Fixes: d2d7867140806 ("mm/hugetlb: enable bootmem allocation from CMA areas") [1] https://sashiko.dev/#/patchset/73521?part=5 Best Regards, Yan, Zi