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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?U6XkhKMN+XbjUJv16e/PIOwLqC7ENCZ3dPAhmyzPk2fNoJqrelZCryy3QnwJ?= =?us-ascii?Q?kwotsdFBafodMemdpw99MiUya8+ksS3w3bIdO4ca6jQYiqh1+RzJF6QTHJOm?= =?us-ascii?Q?DHxA2Sqyfc8OuF83icbnDNIuZ2K4XsP+xoODJjedfSL0GE/wF5rOtshZUVCp?= =?us-ascii?Q?Hlo8mMO5IBGc0ShYtqhj2+Ma5hsx4vSqHYmSxIkXgE8C+4AtyBUSSyrUbybM?= =?us-ascii?Q?9pf+1N6cxCjHueXWwLq316pjqtt89CqaX/iEM/4jLCgLvGPCIT7eQz0wAX5e?= =?us-ascii?Q?w95WTOfvFAY1HW1NSLOssyF+fqiDpm3C/NL73JjjWpwE2waZCWq2sZlZD82O?= =?us-ascii?Q?qOd6XcKwFGO+N12K5l1rWQXq6MZizNLD03rAeicfUReNk4lAAnmtfUlvNw/E?= =?us-ascii?Q?sGTWb4CKf7ggA0yw+jWOSxNXMSKiafpDw6kOJTM10PM30aPNShTElahkp6Dx?= =?us-ascii?Q?IOMXD7GN0ljV7S6drZWFlOM/UzB7jFCiWCi4GAi02vwDo3TK6j9YPgMOKX+t?= =?us-ascii?Q?V68tR4+wYMU9DzjC8ZWaT28iAeQZ+RpJat3G/D7buhjB54o74TDWKV7alroJ?= =?us-ascii?Q?tzT/i455uVwSN+j9I3sCPTsb9oFGipbrqc0Ymr7Bixh0K6Lmc4fhF/wKywdk?= =?us-ascii?Q?0mHHTrO0SxizBlWhXPyLgoQLxys8jizMAKFE7Hk9Z0mkrhzX3+AN8npbFU6q?= =?us-ascii?Q?EphLQ9LsDfDXsske1D8kSdLE0bh7RPHKPDiXvwncv+eKPoDkI1Cj8/XdO1N6?= =?us-ascii?Q?zQdOH/rPerUF6F7CA2kbZZfEY89B3WPzMXG6695WM7Q3PjcGZhu+3gRXVpSF?= =?us-ascii?Q?LO4InErnrnx1ddXvGPvY3k4NrAFW5CEmXGCZ5jokL4hLVuMclOK8KCHKXRzz?= =?us-ascii?Q?wGi9hpxr680lPaZeGMBe1WbDVB9HMQtHbW8geMrPnY/XER8HnzvWIYUGvjZQ?= =?us-ascii?Q?cw17e/OTyLtrttlc+GLB34IK63m67smw+QJ4JJw0qFkwLD1e1I8OGYO2idS3?= =?us-ascii?Q?OQU3yk8fWCnP16VEU9wCjJUVlqDnlAC7rOrZEtxQIYPlmFADZeuwHb/IQvZM?= =?us-ascii?Q?82YELYUGfLfWPg3q7/8KtnzORDRtcF0aipzHbbek0qy+CNTRB3G++xj9J8gI?= =?us-ascii?Q?fPyzOSNnF67gLdDnEcGlD01AibubKPUyo47avHaItsPiib1D0XHiRHj/xXc7?= =?us-ascii?Q?/OoP7yF4gjlJ3FWg8PJ4RxR2bOrZ9zvNN2hetAekgHgkGH3l8Rp1up9/M1qw?= =?us-ascii?Q?32qji39TBieYtrF0noJZlSc2+H7oFzz8tLomdrW+cVrYeIbuuxQINRd2SHyY?= =?us-ascii?Q?XeT7redQh9KKPty5nAn5qH4FJXgzbFgMr68kiKDkxJ1/PJx5gu++UOiiCp8Q?= =?us-ascii?Q?PUyn3zIiKkyueefzRvb/v+TLOMX8mSBT37RAxTKFiFMEC5YACQamiJ9MjTK8?= =?us-ascii?Q?6svbgWIgsb++i8vkgbbPc8M+navkLV41ei/eYetiJ1kFlAd1aSCWcpsrLKgx?= =?us-ascii?Q?iUdGKOpXkZy5Mcr3HfzMnAMmUCBN5O4+DTcvjNUt/5z4mdidNTcvmhCppnme?= =?us-ascii?Q?qH3zLpfaHVisRm3uAj4h+KDlvcY9S+Tw2GVqoR6QZFEwCYBXEHU7y3yBaEbG?= =?us-ascii?Q?07aRzR6G2nWxgvPbH0GnrIhvC8J0UHDpMpQofzC4M5QDpxNBIwdvU20Cbz+m?= =?us-ascii?Q?C5C+NR5rebZUYWWeYt347YbvDDzBlIyNYlNOw/4ZK78nF42lZwCBUP7p7qql?= =?us-ascii?Q?UYfry/mM8Q=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: cfb93e9f-24f1-4e6e-7d79-08dedbcdd3bf X-MS-Exchange-CrossTenant-AuthSource: DS0PR12MB7726.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Jul 2026 02:17:00.2245 (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: 5Kp6J0pe396ATkUWyk29KiCzeyjWc48RfuRg91Xqwx6UIhqqhD1N4oU4/2lxCMpXqGKP6EucToXZ0zBW3558zg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB6444 On 2026-06-03 at 18:01 +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. Correct, obviously I missed this comment when updating 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. It would be nice to make MEMORY_DEVICE_GENERIC the same one day too. But this change looks accurate to me: Reviewed-by: Alistair Popple > No functional change intended. > > Signed-off-by: Li Zhe > --- > 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 f9f8e1af921c..35de3b6a186d 100644 > --- a/mm/mm_init.c > +++ b/mm/mm_init.c > @@ -1027,13 +1027,9 @@ static void __ref __init_zone_device_page(struct page *page, unsigned long pfn, > } > > /* > - * 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