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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?08gTeNUjtb1Rcnq3wzMV/SNqgvOIbIZ/MdGeAf9E/9xJlXaZSpCpwyF2RXeY?= =?us-ascii?Q?zd/E32oN/glKCPwISfV0QwNvfKI98JztS1JF9u5d4CGApUV8keOmmjUnn/Hr?= =?us-ascii?Q?WVmVKRmPJN6ythAV3jo8Y4XhASniHlmM7ejzsc4r1jhSGrx2j2t66x709FIS?= =?us-ascii?Q?FHLWaWBKD+Jsap69hHJuZBqDsNhovVXJSjsqrQn8CpPccjvIBgthl1KiQCxb?= =?us-ascii?Q?14Hj80vezyUq8r9XQDeuunXwJfnlYNqqojuh+wc52d+AHWzadqTlHFBn0FUy?= =?us-ascii?Q?b8RJgfIuERvFMeTg8yNzJNfC6sRRFVY6woAKAGk2JtsfKxYNdCcnUWpwU5N+?= =?us-ascii?Q?M/aXE0RI5a7Tv+qPHb5e6Eo0p8XoBvOlvT/DUpFiIwvYLvZuVW6KzFhdGt7J?= =?us-ascii?Q?C5yHDZV9xuw/gYV2Q4JXJpEd0M2//58MdPUovmpIC4GTMAe82yC9P3hFbvGS?= =?us-ascii?Q?19i+9kao6FiwYydgUJdlb5NkI/lZ1dh2GLEEpYJEm57Y3JkbW+BhV+eWB2ak?= =?us-ascii?Q?Nu5bDwvwpZVi0+U08DPYARKVO3AcWJc1KLEwX9TMzzqWSAVqNvsrtkdG3DGA?= =?us-ascii?Q?oHrtzFk5K/ZiB76o3No/cee74NTE++sIwapGyWXImHL/YMREg10JdhCpaTzF?= =?us-ascii?Q?gEzvZx4HNaTrO+Bbar4jx+BmTKEtgiOCN+sdkuE9sXeSG6vTFyetd1ZZvYqW?= =?us-ascii?Q?Is0c55aVENrTwC3y5sTFFKa0PZQuHjqAVBfMGB+HC4FjfvVTIvmmnsGLte2c?= =?us-ascii?Q?38U+DmSGrLv09gdDOK7fvsEQ3r6haRn1iMl6v8HdY9quyeVQcWEm6xbIW3BT?= =?us-ascii?Q?c6Izlm9E2JwVh2VmnSy2+KEfzEGmzllkW/PN/hHWY36x+g1Axs7CWt2rJ6bY?= =?us-ascii?Q?bLFk/pIbblOv+veHL0KoeyBb14VzmqdgjYYcLokZCYcWcUi/sayAmoSmlc0i?= =?us-ascii?Q?V77rkm0XnAHYIyXdt6uveKGQhiRlyxaTr+u9kemWxXuHkOCsHiT8BjqAzxbz?= =?us-ascii?Q?EeAICZGcVUI6Qd0wNE1licfAJNQ7Y1Uhfi7YlD7bl4Cb4ZYq9DLiiiq3IBG4?= =?us-ascii?Q?cxNhJSbmJ/vWBjvr85tfBW7lg8wUDR9AEjibD7YBp/G3Fxfu9GIOefmam4B0?= =?us-ascii?Q?OKHVlayoeqtnDQXAWn98DJZUqdg00Tulg7CL+8Z3nuaAvaW6D9LVsl0S5jg+?= =?us-ascii?Q?CZlcdC/FmVUUGTE9gpP3vzwAfL7msZew124MlfEaJ9bJdmBl1pOT68fd613x?= =?us-ascii?Q?tNhdbfvaSZrX1s5L89an8TdnWQBef1cc2Sp+j7OhBkKeXubDiT1K+EC8BkQ1?= =?us-ascii?Q?mhyaigty4C/yogaTEZsJv7zIbQQt88Bqe2Y2XTjC9XEN+pao10AnNAlwrJ/o?= =?us-ascii?Q?TgrX1FLpyemlutLBzj6QAqTkLdLkvPwdaP/PAzMQuAUtW1WEjiY9zkccnJrm?= =?us-ascii?Q?a+jf9LCBOmMvKI0aujstjgOQhV/YDciQQSlSQXJyEFp/j87iLzlQ8WSBIwzM?= =?us-ascii?Q?G1z8TqjHcug/V3KvuuoqS8Es5gklbWzx+C5GZJ03YfD7k5TJWCjtzwYANxre?= =?us-ascii?Q?BfEadRmGKjRDVRL2Mr0kSmGKCWKoOr3gamPrQztzFRoHjXZLZfKZ/gXs8om5?= =?us-ascii?Q?bdXak0AZZAZiETA5l92Jv/hthP3auqOswyl60o5X5xl32JPy3aVVHxXSkVJ4?= =?us-ascii?Q?iU4OUeFPLaREzJ3HcBIi1Lb0fllSj3KklKe9AwPBdEM2o7S8?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: ce96b267-d3e3-48ee-d587-08dec0b99224 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Jun 2026 15:13:58.9096 (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: USpsavgXPIgfgtiCuy1f9FOAFsDD9jCUgw1npqbRzXgQzTinqHjOkRchzaoCTAQr X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4313 On 29 May 2026, at 10:55, Luiz Capitulino wrote: > Today, shmem_getattr() sets stat->blksize to PMD size whenever > shmem_huge_global_enabled() returns non-zero. While this works fine > for the normal THP-enabled case as explained by Baolin in [1], this > has two problems: > > 1. Theoretically, when shmem is configured for within_size, this > could set blksize to PMD size even though the allocation may > be a smaller mTHP order > > 2. A future commit will allow shmem THP support to be enabled > even when the CPU doesn't support PMD-sized pages. We should > not allow blksize to be set to PMD size in this case > > In order to fix #1 and prepare for #2, this commit sets blksize > to the size of the highest supported order returned by > shmem_huge_global_enabled(). > > [1] https://lore.kernel.org/linux-mm/6591a74c-7ef9-4614-9ae9-cb2fbed8= 6ebf@linux.alibaba.com/ > > Suggested-by: Baolin Wang > Signed-off-by: Luiz Capitulino > --- > mm/shmem.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > Make sense. Acked-by: Zi Yan Best Regards, Yan, Zi