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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?k8O03t96uT7Nn7y5txrIyNzekhLgDeli7My0f+IVrcGOtfXnDeUlx9cXSnle?= =?us-ascii?Q?Etdb7JgR7iF4whhZWFbCPhNyVw7G5YQYkRCgYZdrBJbFs/JoFAY3Ockuug8R?= =?us-ascii?Q?ecQFYJ7mSrkrutHubHAvWfDupdRIGTEtNDWXOMK3/wk24BpnoN4ulxgZ3TEv?= =?us-ascii?Q?7eRHUFto2h7dwCIvjD/MqirS3zDoVvjv76s5yrT2ovdGms+YDtPPC/Wa1mCN?= =?us-ascii?Q?QDAhR8ELFfE8HPve3kh3IUGbSo+pDdUq5ntZ9grjQjluQ/6APS0gu3lhmYFv?= =?us-ascii?Q?DzKQ35yeZjAAPlLsSYVx1DLQt6Yy5Eat80nGjX5L+5UKLB+MJjog8HJS64/X?= =?us-ascii?Q?IDDWB8moY3LRL+nZLLq1GTK9XKEaYGilM6omJ4VKc6WrmKGfLoLNvAizGavk?= =?us-ascii?Q?GnBZ508RBUKtRY1lbCZlkDIhSEPqJkyjAmX8Q/1ywkYN8afzILVpsqLe+9Zt?= =?us-ascii?Q?lve7w4jwn4C079HB/YCfFPdWgy2MvO0wTgGdRrVHt0kQCMasZ+XS1759PCWq?= =?us-ascii?Q?bFi+pZWVV7trZwUBTup4jfbiCz43inrAjYI5u3NnDuB749+OZJ/9uNLCoRRd?= =?us-ascii?Q?ULc+pjPzk3ye27YkODL0PAI95SYJpkfVcK3H6U6qtpsomRD18alrHBtxNP/M?= =?us-ascii?Q?0SChCrPkLG/ElJfXG9gWG5Jy2ypESFkGFfhadsPPSfl0q9kC4K0Rh+Mpih4k?= =?us-ascii?Q?ghNxqdxnRO14hR6kq99YT3NBhuDhXfSQk1p8X8cXQVIWuEdNSPFl2MHS7C6T?= =?us-ascii?Q?twl2FDfH3vqEuKNraMEr8BdYhRX7TtrDxMszNXvesbgX6u6O0K4XR07XTO+U?= =?us-ascii?Q?J1EOXI0p3GeMdtwSK8Rdwix4T0G4J+qFvrNuhMd2m/vhKZ2c6yRSdH+He5oM?= =?us-ascii?Q?GS9x/eHY+j/f5YQQXYAN9S2SBvzAHUM18x2lyEtfO2OHBt4xBnlDsGXraSPZ?= =?us-ascii?Q?8BDn89x9iM6FLCTNG1RJYyIftEsvZh7NMhUZDhYyIV1tM5KIBI7ga7nWqfEW?= =?us-ascii?Q?kt0YrsZVB97AaGA+A9mJfLUUGVgsEqV87yCg2jbkjEP41t1Gr9LIZXC395+j?= =?us-ascii?Q?B0rTE9gBvufwnkSTsdhqBMts8tyJ11qF9QnDE0m3CD41VdtyNoJBOThEuj7t?= =?us-ascii?Q?Utr7Ep8tGth5MvMpJco63vagcFwkYoAPjjUJTk1vrGqjc7TXr78akUaIGYW2?= =?us-ascii?Q?B2UAWrLAMmOi6v1tooO7sCyVMqrQTFqMzNUk+/833L9jd9RtDmz2ahiL6S4/?= =?us-ascii?Q?UDHi418K0z9uRYovvs2lokht5khhLgUKhdrTRVrUselutyg4oYlp/0u9q8i7?= =?us-ascii?Q?SI+ELg3aA+FBSvrB0CCLWdXVaMvAmQOI9nXZ+odp1UhMOhqjFg/9eGc7lyxr?= =?us-ascii?Q?4GGDyjjpqTargY6E08xUsNS5CHztnr0bjTJbbfghFayrKUDS43JZwh+AOriL?= =?us-ascii?Q?zVHCj7nAq5fgX7j32rBz7mOTnbDPIUTXK+hx4xDnpuKVtEInGTrKzINZRO0g?= =?us-ascii?Q?040Fn9rDSbZ32y5i09uy37dcjUX/D9sWiDWSOVT2I+AvMZ5AX5AwK22hj+Fw?= =?us-ascii?Q?amJ7DQHbb/0WbcQfR+Rst9RtVlyvmMtJvW02g/pmiMmC9RB0L+FgcyA9XWVA?= =?us-ascii?Q?PlfE5bmDb26vYswrGF9t5dHy4LD/amPUjUYKG6aCAVstPN/gRVSAU59PG7qR?= =?us-ascii?Q?M3NZv2Pj8Re0G+Z1FCgk4Fcek671iG5CX0cNUE4YWNs4nXe9?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 1ff64b82-7ac0-40c3-5300-08ded2ef51c6 X-MS-Exchange-CrossTenant-AuthSource: IA0PR12MB8374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Jun 2026 19:24:04.5257 (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: GWvdstHj6HIA78oL8MF56E94NEI8Neiyhvk5OxwX6VPxOUCC4w9ZLOaXS83qAHyE X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB5781 On 25 Jun 2026, at 15:20, Andrew Morton wrote: > On Thu, 25 Jun 2026 14:26:51 -0400 "Zi Yan" wrote: > >>> +static ssize_t page_owner_write(struct file *file, >>> + const char __user *buf, >>> + size_t count, loff_t *ppos) >>> +{ >>> + char *kbuf; >>> + char *orig; >>> + char *token; >>> + int ret; >>> + size_t max_input_len; >> >> This can be const size_t max_input_len = 32 with the comment above it. > > I don't think that local adds any value, really. How about > > --- a/mm/page_owner.c~mm-page_owner-add-print_mode-filter-fix > +++ a/mm/page_owner.c > @@ -933,7 +933,6 @@ static ssize_t page_owner_write(struct f > char *orig; > char *token; > int ret; > - size_t max_input_len; > struct page_owner_filter_state *state = file->private_data; > enum page_owner_print_mode new_print_mode; > unsigned long flags; > @@ -942,9 +941,7 @@ static ssize_t page_owner_write(struct f > * Maximum input length for filter commands: > * 32: print_mode command max length is 17 ("mode=stack_handle"). > */ > - max_input_len = 32; > - > - if (count > max_input_len) > + if (count > 32) > return -EINVAL; > > kbuf = memdup_user_nul(buf, count); > _ Looks good to me. Best Regards, Yan, Zi