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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?x2Ne+bILIuEu4dngwBgQhRzjiAaVCVaEmH3jFuxMqsWbdTQb6fTbKf0FFJc5?= =?us-ascii?Q?Fv+KSzm7TE0YZV9eCP6spmV4AmllIcMtKeT9Q2GFBVJuQooK0nNf9N+b61xq?= =?us-ascii?Q?T5LOHCCBSm7VAhXM6Nf0WAmhYSrfsfbubo6RI7Ttnoog0Rjk2EqYs76fLtSp?= =?us-ascii?Q?z/9Nyiwc7prgQ8Zyr0ceE9ZHrbJD1Jc75o9SWk2Az0+HX4SpX0XN7G5thuKD?= =?us-ascii?Q?O2p38Q+rxaQzLca8PXWcOXuQmABJisFfeS9JSC8FoT/Vd9MzobkfJQG/N9Oq?= =?us-ascii?Q?uae37a7wpP/C2xhaSrcvpgcTKM/0MaoqJK/QHJL0IdiAOm2BvdVyQPynJpgI?= =?us-ascii?Q?lhVRRNLumn6W+tiro2W8rORkiEOkWiUhbLnacqZlpkwdsNX0ZoXaCHSS19IX?= =?us-ascii?Q?I4p21CSUzHFDgRERENwSV39ZNcQg4Nd8LdU47EfGgjGAYAXqpIYd65qh9SVv?= =?us-ascii?Q?sJ3q+PEng7pgrcrAuzrTsocEYxeO+e1XW6VbnoJDCRqg2rffOhLfej/gdmg1?= =?us-ascii?Q?+4DJHFtKEnN0dM8QtXcO8oUR8o0I1o0DJLeDuuANJ1p1Tnkd+Id5ZeEa7AhY?= =?us-ascii?Q?RfGr5FegGfqBQCIhnCn6PxAIPfevO/Rmk0G6O+Q5lHbaF9mDqjH1i6nY7XHq?= =?us-ascii?Q?O25vCP/ohSNhaZG+eyw/GD9/Db1tkQtzADDSl4+wovJ/K929Sr2+PXwGqKRz?= =?us-ascii?Q?tz0hqlYiVPczRnFAAgOGP/5H4XwpWNByxP3wD/Nx5IaRrMKpPfzn/dScPKev?= =?us-ascii?Q?7l3PcWw2gT9JQLF6eg+AxqB4rGu6/pBU7l2Ypk2Fdn0xuGw8mB/ytbIr0Lc+?= =?us-ascii?Q?WCoygHdIk9CXPYlgEerwfNvDUI3CbK9gAN9a3xIfzK7Mmc+Mzx57oje6gntS?= =?us-ascii?Q?kzc9+t8tiNxlFD/JmSLfJoXZTe+Nry9kHL/A654IlVqa0X35u7VY3FJpyBe4?= =?us-ascii?Q?tBkTH2cHrAT9PW84F3Nq8lKbWbmWxiA18oc8bMohCoPPUgkwe1iAq5cXUXzp?= =?us-ascii?Q?gJJ7y5n5Kau2l7x80Yattb3zrN0SJItX2MCXlJrNVju5UtrfVLtjbSfSD/4m?= =?us-ascii?Q?BtEpPcc1yr10rSEDubJKq3+MLrhcBNnBgp08gSXgK68LzB6bb0XoHnPFLXtg?= =?us-ascii?Q?ZZtCKmA/ABTTMJ/byrUqk8iQDjbKp7xh4RukcrSKLhk1UdJHzh3kH2uRnI4k?= =?us-ascii?Q?tdt8CW8hSZ++pwJlYlPN6u+Aq96lcrXwSS629gwUewOP+LZK0GCKoq/fER2m?= =?us-ascii?Q?SQ5VvAv0LpsbOdoVr+4SstM0dd6C+WhEPihjcFEW5ZdjcF0zUjnbNiuL6VXe?= =?us-ascii?Q?QrsEd3NR+73vzde7s4mYCOu2+sAmEyKZ4Eidqufv+ZO3tygXB5AI3AzDuN5I?= =?us-ascii?Q?F5hARQc2Qz1CBc84WvuPa1FARpHfKJ2G+ootW3wbbHNNDAEkFEccpjLOBoqa?= =?us-ascii?Q?ouLvwSmSupL1AJQlOcnR3Kvwz0SIU0CXE6Ub6Y5MbZO1LKs2YNyNtUQbOU0U?= =?us-ascii?Q?1dmsoQMfKRE1u4178h5CYHAhunZ8Ke86zn0ROOxDGpKXD/UriLcijQasNtil?= =?us-ascii?Q?eAF9OkzKnNBSZXzbE+c0rfu6O5+wJnTfj6epIciGiwzKxJQZN61zV0yUE3+9?= =?us-ascii?Q?XCxkT0Zta1HTOLnHfjVHv3gDZoCxKcFXK1kRIrzGO89ElIU/+c/1dOGooKx0?= =?us-ascii?Q?1C14JMGJEOV9fQFsbL4/wRfbkqZxkyZp/Lj91IuBFd+LBV3/?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5faacaf2-9caa-45f6-11f2-08df1011cc4a X-MS-Exchange-CrossTenant-AuthSource: IA0PR12MB8374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Sep 2026 14:34:34.0022 (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: BZiipEPDe0hkiyylbmuDzxtCcv34pung/5a2Vmf6WiHVWb6rSIIAPxw2DQvPfF/Z X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PPF4D923B935 On 11 Sep 2026, at 0:04, Baolin Wang wrote: > According to Documentation/mm/transhuge.rst, MADV_COLLAPSE is expected = to > ignore any THP or mTHP interface settings. > > However, after commit 6beeab870e70 ("mm: shmem: move shmem_huge_global_= enabled() > into shmem_allowable_huge_orders()"), performing MADV_COLLAPSE on shmem= > will depend on /sys/.../hugepages-2048kB/shmem_enabled being set to "in= herit" > (although that is the default), which can cause MADV_COLLAPSE to fail > unexpectedly. > > Fix this by returning the result of shmem_huge_global_enabled() directl= y > when MADV_COLLAPSE is requested, allowing PMD-order collapse while igno= ring > shmem THP/mTHP settings. > > Fixes: 6beeab870e70 ("mm: shmem: move shmem_huge_global_enabled() into = shmem_allowable_huge_orders()") > Reported-by: Kiryl Shutsemau (Meta) > Closes: https://lore.kernel.org/all/20260908125105.1510704-7-kirill@shu= temov.name/ > Signed-off-by: Baolin Wang > --- > Hi Kiryl, > > I did not update the selftests, as I hope this fix will be merged first= =2E > After this fix has landed, I can send a patch to update the selftests. > --- > mm/shmem.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > Makes sense. Acked-by: Zi Yan Best Regards, Yan, Zi