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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?VbAeylw0XYiavNwxL9peU0BqfDa0gpqui0BzYfAeJP+GIJnlMoHhyf0pmRH9?= =?us-ascii?Q?qC1AKZQpzG2wrfvf7I7h4mcWcd7gRcpiUBngbla3W57QJrrH5QFN6PJilZta?= =?us-ascii?Q?Jg4vuOjesWBXZ+g/ZcETTGGYP2MJLJz+xTio6Gh3PNRKvmSoXjDeevbC/o/p?= =?us-ascii?Q?8jd0ITIc+lH6p4W6B3w66OuKh1/NHzfJVIs9b+jJgM51AHSpEDwU97meoxHa?= =?us-ascii?Q?4qKxleVFpIp5FP/idEJ7XeaBwD0T6b7O+DguIdIf8OtjmK1+H2Rp2s/SlVt/?= =?us-ascii?Q?ODZAGFB1LT1/IC6JrVknvO/ERBtVSA/JAW7mDgLiSjMVatXIgXLYt/pw32cX?= =?us-ascii?Q?WkdeRaRTNV7Ll560jm2mwE+B/4tTu5EpVf+6HKAKtugvjvWCZVC6AHz849kc?= =?us-ascii?Q?PSXvaK+w79D8t+v1kUAFRWeiM04+q8vUIKED8hIeJ6dKCG8a8uQel+4LyO6K?= =?us-ascii?Q?KplQbKXiKSSu5HH8a75BVl8M1YmaPtUdjXsiSK0vVTDWqVXEXjNLcZIH53hf?= =?us-ascii?Q?/OL6Wmco4OmWfDqFrSiizfwYDp+N+qftPXrLHHk+1Oce+HRgwl94trAd3aXn?= =?us-ascii?Q?6CpOePlJO4VG/J6CTTsXUMO10aR0c44KzmrQVd7SCYZiGRZVczfBfW5VmUOD?= =?us-ascii?Q?A3JYMdYNQdeqIhqL7LsSnvcIHEqz+E604YpPXC0EMtt8TBvxvsKOYTjrWb7g?= =?us-ascii?Q?78nSiJIXSg7SJqQJ6K0gTxXARB4p8Zjvn7bM5l1mS6BO2J8XJ+sYFnnaa5mo?= =?us-ascii?Q?KRLhvQeRN/H3cBVAfG74eGhDEaNQHOzyJzHHkx+yYasLv1sGDjDEX3xUyZqB?= =?us-ascii?Q?u29XyDPmbA43gCb37bd/5XJ1wf8lbRyhFzMBaplv8QuubQss8Oj3ddbpJVBv?= =?us-ascii?Q?Ff1o9pmT8oPifVxU/PTmLtPoTbT/vr7rQTO4EnRMQiUWyVjREJAAjlzwQ8ob?= =?us-ascii?Q?K/Q2z/dgos8FtoisYxFPAnyCvdizIpScQYNQ2G/uA+un6IGB2cw76GQDgFqa?= =?us-ascii?Q?OVgpHkgJVwaWrPQfCG5BdNfEqJV821ySqIc1I0PmVcYfT40/XCSemTBwizcz?= =?us-ascii?Q?EKZFum37OsIstB2kaLdDQTDp6taPt5GsHTa4G7p49V2Lf1u0ZRE4dHrKnZq1?= =?us-ascii?Q?MEDLGR5mPUjRiLZF7wGXBU71nZMn78AnLd40eTJ5EZU0M9ojktXHyykY6Ujs?= =?us-ascii?Q?xbIvoCO/cyX9zSS2KrlqVcgfNcawr4Kn2tFCAE7vg9iYMFowTPICLj8UsrDx?= =?us-ascii?Q?km8ekGlRtef3JNYLf9c5tYZ3NmMWLcmO3YVI0AO9qs62LW2NnZLSEja0CxQQ?= =?us-ascii?Q?0MoNwYIsGB89N0HIt7ZWB5VcusIv53RygAVTNXwg2NJRFKRFhYYy6fv9k4i0?= =?us-ascii?Q?FNKXO+/RwuN0sBjKq0zCwlURzjGadP4F584OPN9MqlP/YoKqF0lXC+VdBvbT?= =?us-ascii?Q?L7AC8QPDNw8UH9lhPDVx19UzMUPjy7M2uBdYHpCb21FSD/12p91v/OcylB7W?= =?us-ascii?Q?knINWQRkijbeQlhpOSVxclUGaLHCsSKEGU61g5GnYcoPv/DODGrFerwHa3Vt?= =?us-ascii?Q?wqF07i7QSKdVVGxTH2QFA8xE5N/PoV1i8XILkEvul/+/+icmnWkdl+CXCQ5Y?= =?us-ascii?Q?SA=3D=3D?= X-OriginatorOrg: memverge.com X-MS-Exchange-CrossTenant-Network-Message-Id: 49529720-dd94-4c97-5f62-08dbb2d63faf X-MS-Exchange-CrossTenant-AuthSource: SJ0PR17MB5512.namprd17.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Sep 2023 14:49:06.6818 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 5c90cb59-37e7-4c81-9c07-00473d5fb682 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: dOTFPMPUtHFobeRbMW2QLg9wcl7eCUwk9PoWe33cH31Dt2Jz4J7AhWpFDWrYP2+WJoqnqrUakeqAMftluowTt/89ACVbqTH+RzSRs2aljuo= X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR17MB4815 Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On Sun, Sep 10, 2023 at 02:36:40PM -0600, Jonathan Corbet wrote: > Gregory Price writes: > > > Similar to the move_pages system call, instead of taking a pid and > > list of virtual addresses, this system call takes a list of physical > > addresses. > > > > Because there is no task to validate the memory policy against, each > > page needs to be interrogated to determine whether the migration is > > valid, and all tasks that map it need to be interrogated. > > > > This is accomplished via an rmap_walk on the folio containing > > the page, and interrogating all tasks that map the page. > > > > Each page must be interrogated individually, which should be > > considered when using this to migrate shared regions. > > > > The remaining logic is the same as the move_pages syscall. One > > change to do_pages_move is made (to check whether an mm_struct is > > passed) in order to re-use the existing migration code. > > > > Signed-off-by: Gregory Price > > --- > > arch/x86/entry/syscalls/syscall_32.tbl | 1 + > > arch/x86/entry/syscalls/syscall_64.tbl | 1 + > > include/linux/syscalls.h | 5 + > > include/uapi/asm-generic/unistd.h | 8 +- > > kernel/sys_ni.c | 1 + > > mm/migrate.c | 178 +++++++++++++++++++++++- > > tools/include/uapi/asm-generic/unistd.h | 8 +- > > 7 files changed, 197 insertions(+), 5 deletions(-) > > So this is probably a silly question, but just to be sure ... what is > the permission model for this system call? As far as I can tell, the > ability to move pages is entirely unrestricted, with the exception of > pages that would need MPOL_MF_MOVE_ALL. If so, that seems undesirable, > but probably I'm just missing something ... ? > > Thanks, > > jon Not silly, looks like when U dropped the CAP_SYS_NICE check (no task to check against), check i neglected to add a CAP_SYS_ADMIN check. Oversight on my part, I'll work it in with other feedback. Thanks! ~Gregory