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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?xDbinSbv7FdrGIyT+q+LaSTa95mvcemK7kO5ZrpkP6J9kUQt0i44dwntzgOA?= =?us-ascii?Q?ReCDZ7iQ6fGfzF/oW69CFCLSpnASm5GIF2rM9u8uU94+Bxdx1UIj2ljoC8Wd?= =?us-ascii?Q?93nNKrjhxFSq1hWcq8Xt003ysGyYejE7gR2JszPi9KJRJhqR/fzFUq193znq?= =?us-ascii?Q?6w2uL2iWyy8kEXb2pvHlWt6wkFvjOj+UiFabmMjhGXIe/SUrvGXaGIqAvHMJ?= =?us-ascii?Q?DiBo4A89IW2xqltoEXQchppV6fkJ0eANDbQWU13JpuZI9xY7Nz2RChm8TyuD?= =?us-ascii?Q?ogT42MefNYIcb80yUoeOX4thBkIDnf5rB8roOc1XB2lvPqyGs++2X0UYSNsj?= =?us-ascii?Q?+Ek46Omvbi08eaHiNsfyse/ojRkrEneX8sP6KXStxjnRlujNqpVGINBnv5ga?= =?us-ascii?Q?EOwUcfFZgGojc27AAC6+BFKybaP5PkJWYkZTFy/bSjvftBo7IDTZgTPtjWPJ?= =?us-ascii?Q?S+7PkpUWY0ZzBoPUcWWsHxBCl3qZ9e93ajWsoIGzRYoyh/AzrzhqtoQbj8vw?= =?us-ascii?Q?VpJ9iL3Stj5fNy7TBz4RbzRKUuVhmG2RogWFYlh8x7UgO6i0sVYXvNPZPDJU?= =?us-ascii?Q?P2gq2YfHBxxws48OV4YZG8FPjHf5D0b98m2w0rnsR5CkYJGPaHTjjzbU2QsC?= =?us-ascii?Q?WdYUtQ0PlgVLfgIGNxhNipnLeaAIjgb76NZTItza9gYyZizhIlQsOuhX6nf5?= =?us-ascii?Q?edQAIXddWjedkv1smR/M9n4bU70iEtA65J9Fg/Q2NYGTShaXSpv1+FPaUItG?= =?us-ascii?Q?GsV3P7NOy1Bp+ZvTKUNVGpnoCPlFFDN9kCfKttPq6tp6Z3gfWRm/1+lXXhqb?= =?us-ascii?Q?jotwuz6+hoX4CEID6mkjnd5WJe7nx8gBIGf5Rm/0jJEiAhA6w4U2QzPiOuHS?= =?us-ascii?Q?G5gHOhgGSseti1iZ/WtMhDsHyDACuv44mxJIDxbUd0bZ1laMtPbh9GcsbZp6?= =?us-ascii?Q?cTBgfG/9NvN65UB9XLxRAasUn0O9WjTeY96C2B6yY+nLGN8jtneDnF5hBUDn?= =?us-ascii?Q?Xf3XC2KtCrHPGt54YaCYK2wyOp2nsbhOKwY1P+w3xEvV9HXPAS9mZf1ewZ4+?= =?us-ascii?Q?yW+40fda2pVTO32h/Bl7Ad35WTUcdTXI1/c3Tk2FtNNvOKltY8F9O1aU9jkL?= =?us-ascii?Q?1Ig5zcLUj5ehra2O1iJ+6AeJnMq1iJotxuMUWnZn2KD1wZInKIRMQ/XzwNZi?= =?us-ascii?Q?H6H6RNzG0aqRNV4Tpd1AAw87zRu6Jk+vr/bRS6gjhoH8PjqUm4QcqGiu77NT?= =?us-ascii?Q?2ZJonqb+3OnX/JXhh0ZmtOORvnKyjoyChjgG8U5+Mt9RIK2/hM8034ydaaWj?= =?us-ascii?Q?otqdpSGNylyQ1xAXarucN35l2sKw8LXlmW5BqXO3lk4Tvix0YwhfO/YKrws8?= =?us-ascii?Q?6mTn7hruQZSQJiF/SRr+GtP2frm4wHWJwMeciNwUTlG5hKwR036p+PeG4AeO?= =?us-ascii?Q?hFyRSHuiOlfevYNgJADi1O80UY+aXho0IiNdRkpLsmZQhkJmRIFnx73k/J1w?= =?us-ascii?Q?QiiB1YkgsWSRx5Lk6KxOeVvDnXUcaHSVWqJdPCp5zxTzI5B3NkB80xyKNCUn?= =?us-ascii?Q?KWFl8FLb5hjhHi5fZTwlTuQ7wpjQOb2ySPEZElYF?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 95b2c6cd-cf08-4bb4-de84-08ddea42da55 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Sep 2025 17:05:00.9838 (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: 0K2b5f121PxcR833qz+mmdpQVq7RmzfmP8ZvghqhRGwjf6SmhnIU8lYr5bM7w/uX X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB8904 On 2 Sep 2025, at 12:25, David Hildenbrand wrote: > When checking for actual tail or head pages of a folio, we must make > sure that the KPF_COMPOUND_HEAD/KPF_COMPOUND_TAIL flag is paired with > KPF_THP. > > For example, if we have another large folio after our large folio in > physical memory, our "pfn_flags & (KPF_THP | KPF_COMPOUND_TAIL" would > trigger even though it's actually a head page of the next folio. > > If is_backed_by_folio() returns a wrong result, split_pte_mapped_thp() > can fail with "Some THPs are missing during mremap". > > Fix it by checking for head/tail pages of folios properly. Add > folio_tail_flags/folio_head_flags to improve readability and use these > masks also when just testing for any compound page. > > Fixes: 169b456b0162 ("selftests/mm: reimplement is_backed_by_thp() with= more precise check") > Signed-off-by: David Hildenbrand > --- > tools/testing/selftests/mm/split_huge_page_test.c | 15 +++++++--------= > 1 file changed, 7 insertions(+), 8 deletions(-) > LGTM. Thanks for fixing it. Reviewed-by: Zi Yan Best Regards, Yan, Zi