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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?PlRS3w5eBE5hyG/uDObQYHCeUat3kxv0lJ6pA3jIrjHi1VVHnaKRREn0fIdW?= =?us-ascii?Q?PFd8IBO21FA3yhx7ThxsyjtiC4IUf1/Pfd78y9OaDIHAw0GlZrK418tEUVjN?= =?us-ascii?Q?PLzyXH3hg//DA0cjERTQBnw1aqK92FThcRC+A79bkstvSRHS9MBZ/gl6ku1m?= =?us-ascii?Q?8OntcJ2d02Z/9CTL2YOYAmLIWKXdr4jUFxsaqFtf+e9i9Ht93JCL2/ZRkYfw?= =?us-ascii?Q?rmBlQffCbkOgnhHsmjAHfpsEx56yGiWGNltxcumUdIYHo2SWT8uRD6/mDN1i?= =?us-ascii?Q?Jdlt4hMnJ9iXJGiHqLRJ7TwsW0wJqZvodkDIJKy3Po9g9m7fVey1k9hXhhkt?= =?us-ascii?Q?/1mn3pM+YxussOoXkLutnNsNu3dv0I9+bCL84KjUSite653V0pe/ru9x6HUj?= =?us-ascii?Q?x9XL5UiXP3D2nDh3g4LdIkrFvDgoOFs4pcL3LZgPv0FHprIcsLGgcMK+Zadn?= =?us-ascii?Q?N9+NJ8oOGu+9Z1fYDCj/TZ14s//gX6bSUjMwCTgXrXK1ubG23KVlqhWQ0qB8?= =?us-ascii?Q?fJYbdPnutABbW5CLpVCqYuXiZJTrAx3ei7TIoXGQsVp9EvXcXCRBUJ76H0SW?= =?us-ascii?Q?NNu1wKVoWj9EytD9Shb44lRKoN6eJuCTVzDR/JiNZ0JC8XNj7N4WvEV+aUED?= =?us-ascii?Q?qFF0Rua8yDI3ocv5NjCV8VD2ImUomfrU3/fzqfaaXLtutvFN6JQOyuaE+QrG?= =?us-ascii?Q?tIEiXWRNW/MtwuN3MbZuFWQcJKrg2q7D5WmdzByUfKNY0uSPE7usGDao7H2o?= =?us-ascii?Q?35dtDeV9wGcy34IkKINdlzdKrrq+oGZULoU3VtzPE0CCZ2REmOumOHTNg6sP?= =?us-ascii?Q?dZY4Dxl1m4bho6886KoomGjsFqSS4ArST3S6/AQ+hImZN6QX9AxzKSP2VN0K?= =?us-ascii?Q?YhIxe2LYmwDUUUezOnlz/1QU8IobtBvzYdqZfEZu+1+rJG9U8VA2OtY2Dspn?= =?us-ascii?Q?/J/ICYmubE41o7Yrz3iP8zkR5jfq6oN7CquW3ZEn5c2YlsEzp5lo1xZeopGk?= =?us-ascii?Q?ZoCQFQE0tZsSllP0w58jrplEtD9mec9CJOcYgrK88Pbr74vIvoSPpOkIfu0s?= =?us-ascii?Q?naBCN3CeRi6xCpPLtOMX3eEZGnaWluFIvHs+2RgNuREkdWMPtY75E0Z39P+7?= =?us-ascii?Q?D/3dLDqN6OZXSOSbfZjgeDtean3m/KaOE7e3kZkJBAtQlKtUaCvNPeTtXAfo?= =?us-ascii?Q?dFtdkCZleIHT5uesZONJRb3pOfzcndoSAJYELKyIhbakJRQdleeihhJPmijY?= =?us-ascii?Q?+bECzW1u2q0gP5MQgn6epORl/vk5yyP7dNU3WlR7YPcdbYfNcPLdiUbgrzeq?= =?us-ascii?Q?MP+o96NOUhppRpT++MrQj5+nw5LJCf9ZnoAeMSUuWRofBzSm4/Y8wTh49FSR?= =?us-ascii?Q?vL7C4jF/oKoV4FITQu9pxtkda6CQSE/tPWnGBMuvfzYZQkXBEKlLFKWcGRRI?= =?us-ascii?Q?F/dIK81ooQEGbyqS6dU4LQsAOnm5QMOoObc6HU5DVlHz+ARK74Myz/ACqPMo?= =?us-ascii?Q?x6VjxRe0JHLD+1bHFVcwTmnt9sBEVtvsSVFL5x+e85zN/uXwQvXm1SRuQEC6?= =?us-ascii?Q?qngGclP/X+DNcJaK4ILsrn4oci0h6IBfkyP2+m2RR18MJrAtlD2jWt5Rpvny?= =?us-ascii?Q?Q2+absKA60u3L/2qgnoch3ydcpvXcstSP7GoAUsxQN4eYn7QEEswgUECHsjr?= =?us-ascii?Q?ZZFTJS6LAb2Upic5w4d77n96LVJAa41bGot0GvMhz7DxV6Rq?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5b76fa87-5cdc-4ef5-8456-08dea5603086 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Apr 2026 19:56:08.3671 (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: jE38TqffduucAri0cKvhfEtEXEetr0roPlbhmUHTY2TgWMZEKwYDiRBWrJXw6hUN X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB8426 On 28 Apr 2026, at 9:31, Vineet Agarwal wrote: > file_setup_area() currently allocates anonymous memory, fills it, > and writes it into the backing file used for collapse testing. > > Instead of copying data through write(), resize the file with > ftruncate(), map it directly with MAP_SHARED, and initialize the > mapped area in place. > > This simplifies the setup path and avoids the need for explicit > partial write handling. > > Signed-off-by: Vineet Agarwal > > v3 -> v4: > - Restore unrelated blank line removal > - Restore original close()/munmap() ordering > --- > tools/testing/selftests/mm/khugepaged.c | 14 ++++++++++++-- > 1 file changed, 12 insertions(+), 2 deletions(-) This patch breaks the khugepaged test for READ_ONLY_THP_FOR_FS. When I ran sudo ./khugepaged all:file ~/ on ext4, collapse_max_ptes_none (khugepaged:file) fails. Run test: collapse_max_ptes_none (khugepaged:file) Creating /mnt/test/collapse_test_file for collapse... OK Opening /mnt/test/collapse_test_file read only for collapse... OK Maybe collapse with max_ptes_none exceeded.... Fail Unexpected huge page Restore THP and khugepaged settings... OK Reverting the change fixes the issue. It is also causing issues for my READ_ONLY_THP_FOR_FS removal patchset. > > diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/se= lftests/mm/khugepaged.c > index 3fe7ef04ac62..6e929a484a1b 100644 > --- a/tools/testing/selftests/mm/khugepaged.c > +++ b/tools/testing/selftests/mm/khugepaged.c > @@ -381,9 +381,19 @@ static void *file_setup_area(int nr_hpages) > } > > size =3D nr_hpages * hpage_pmd_size; > - p =3D alloc_mapping(nr_hpages); > + if (ftruncate(fd, size)) { > + perror("ftruncate()"); > + close(fd); > + exit(EXIT_FAILURE); > + } > + p =3D mmap(BASE_ADDR, size, PROT_READ | PROT_WRITE, > + MAP_SHARED, fd, 0); > + if (p =3D=3D MAP_FAILED || p !=3D BASE_ADDR) { > + perror("mmap()"); > + close(fd); > + exit(EXIT_FAILURE); > + } > fill_memory(p, 0, size); > - write(fd, p, size); > close(fd); > munmap(p, size); > success("OK"); > -- = > 2.54.0 The code looks OK, but I have not had time to look into it yet. Best Regards, Yan, Zi