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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?XL70I+Pb4wsPT87ywHYOA1zFowSo3MlrxEhMPTUDY7IIKClT3Kq0sQh5Fg5e?= =?us-ascii?Q?Hk0Zl/oAK8wXWJ4Eaz5G8L9siIjdVzXL3JGC3DTjkXTu6HgsZJR40KSNLwDQ?= =?us-ascii?Q?xPTk2fuiEjkRPGLBDMDV/Xz6vR2khBTFNyicssyesJdAm86bZEoEg6ynxnv2?= =?us-ascii?Q?QLXJvTK9R9RC0Q8+FQ0q4kIe6F4GjAXY1UDJrgjQ4qCq/CFxPt7lMdHs8Xky?= =?us-ascii?Q?P9W1n25tBbDUGB6G41GDNYqUSHdvGFlB+BwJBhwB8wk+iyCQ13gBssTVtyOV?= =?us-ascii?Q?XWyUBuyYaVgV+qPnOSGLktL82uwiE2CCpAyNxklxz9OG9du/GnOPcmtxQA4p?= =?us-ascii?Q?Jg8KFOFZH2uCJ4MQgHkK0oaxPtOwq8/SGETNPgHloz5UTDTzEkqxDkYcM78v?= =?us-ascii?Q?T2dWpL5E3wZVL/Kl4EfvQHaDHtfEaE9CRSmzEX0BWhGc6//XfKJxuA57LsZ5?= =?us-ascii?Q?Gf60bDb/1JYiWZ/vrKBP3XtsHViZnneY+7RpDptFXCWjpg1tihZSMMiydNAA?= =?us-ascii?Q?0oCBCIkJuEsQrZRq5+TckLpPxLohWHrSQvtqD0d9cV4r2FewgLITYy4YleP6?= =?us-ascii?Q?IeJOoyxUZB/FJaMYtMTlbCegzcVom9oAk7/kfU9SB1A8UiTTTsdEEKF8GKJh?= =?us-ascii?Q?KTb+F2fHnTlImh2QILFcFOEslyRJ+5pRnCLjy55TiYtLhbITCZ85qY5yWLyY?= =?us-ascii?Q?vgCpioCNFowXJ0XXCJ8A1v9/dQ/UEqQWrpJiUqewxnPvG/4F7hxfZBeXvQ+n?= =?us-ascii?Q?2OiZqE9fzPD6ade3OwKl5QUVSYAAy4tMoaZYq7qi8bxw2tbIWybNCU80ALnc?= =?us-ascii?Q?ozJW5Ei+Cne2vYVY1KtPkusL7jzlvLX9iRATf68WgjHbowqHAhJu8B97Q7Qo?= =?us-ascii?Q?FCjm0Juy9YCQoUWDH3+6F2nzsKZ1lFrKYMBEu+JkDfIC8VtYPo1MtgIwOP/c?= =?us-ascii?Q?EoC3cQDQs9SnhUeOYp2+Y8NYAyCPNl/hbrZskumup6wYTunfqBLxCeRldinW?= =?us-ascii?Q?+sQXu1H/5A0YDp7kRMXBMaWGtpj6ncQS4H3oM3wzexpvGyb+cBfX9gr8go4H?= =?us-ascii?Q?mL4po8zLIfOFV0NAEl7Nc/xTFb8JzfvY9CxkydxuvmpeThfyyZOTqWJlGfis?= =?us-ascii?Q?dYLjnV2BYAo3697+3OWbvHC8twerxTI05cZFAgeKfbRImT0RuXTgzWKDBpoe?= =?us-ascii?Q?ZVuvJ+61ZHXIiUbM+3Q5UHf+vLvvOH3MM/Bw+2Ns4zSUZUnYyZJZtQvNAAJc?= =?us-ascii?Q?31G+YIC5iL4FOM1McYwK6vmHOo7wm6xtKtUigBTAdXLkt6c4l5XXcx08WzfS?= =?us-ascii?Q?2A7YO306NjhTcdcKnaY8CtbyUbXdHvKB4tEQtx3ITGW4MNEn+dGVNYihU/Sm?= =?us-ascii?Q?CJqmngFT4ce08Z5jJ1kp5sf4zkIXE0tvus9tEjwNBj/j6kDmyvHl5bin7eEn?= =?us-ascii?Q?RjbpD2OI4KYYrwUE5QsLXP2ujOVHOf3wKPyBGSK28mxn6Ld+7S9Fg4MydPPk?= =?us-ascii?Q?UVF5zVmFxboDVnXIFaeVYpLGGxO6zchS+TMz6fB+LeRM1T3729MX5OizMtaB?= =?us-ascii?Q?nrrXzlH8o3WuHpOLRwSlshi6icLCGbaFFSdHJdrD59fU1IES8ciBM2jzHwXa?= =?us-ascii?Q?7BSu39q3434s3M+dSywvhoo/BMoTOObepf+DyaqtexT0KSX4pklM9oG5c7fg?= =?us-ascii?Q?l9lOH3UHCUMboMyv6ESPasOed0enGJ1hnw0NuRniS5p9oMdhB9lKrn6LnTPa?= =?us-ascii?Q?4CNSZ/z9AA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: de79c827-797d-4be3-c814-08dedbcf6d05 X-MS-Exchange-CrossTenant-AuthSource: DS0PR12MB7726.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Jul 2026 02:28:26.8468 (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: MntOzAphthj45sC8qzsnR/TDIKpWq0/NoVhsOzeRDAKDahrSlgLY2UgYPplv4sLHLDwOhesJIX+Y0uietIcC3Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB6562 On 2026-07-01 at 19:05 +1000, Li Zhe wrote... > The comment in __init_zone_device_page() still uses the old > MEMORY_TYPE_* names and implies that FS_DAX pages regain a > refcount of 1 in the free path. That no longer matches the code. > > Update the comment to describe the current policy correctly: > MEMORY_DEVICE_GENERIC pages regain a refcount of 1 in the free path, > while the remaining ZONE_DEVICE types start from 0 here and raise the > count again when the allocator or driver hands the page out. > > No functional change intended. > > Signed-off-by: Li Zhe Accidentally just sent my response on v4, but this looks correct to me: Reviewed-by: Alistair Popple > --- > mm/mm_init.c | 10 +++------- > 1 file changed, 3 insertions(+), 7 deletions(-) > > diff --git a/mm/mm_init.c b/mm/mm_init.c > index 0f64909e8d20..95808ab5cfdb 100644 > --- a/mm/mm_init.c > +++ b/mm/mm_init.c > @@ -1030,13 +1030,9 @@ static void __ref __init_zone_device_page(struct page *page, unsigned long pfn, > page->zone_device_data = NULL; > > /* > - * ZONE_DEVICE pages other than MEMORY_TYPE_GENERIC are released > - * directly to the driver page allocator which will set the page count > - * to 1 when allocating the page. > - * > - * MEMORY_TYPE_GENERIC and MEMORY_TYPE_FS_DAX pages automatically have > - * their refcount reset to one whenever they are freed (ie. after > - * their refcount drops to 0). > + * MEMORY_DEVICE_GENERIC pages regain a refcount of 1 in the free > + * path. The remaining ZONE_DEVICE types start from 0 here and raise > + * the count again when the allocator or driver hands the page out. > */ > switch (pgmap->type) { > case MEMORY_DEVICE_FS_DAX: > -- > 2.20.1