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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?D1C25djG/vW3MRuH1xhXciRmPXVX2rwQ5YGrf6ds8D6pkBT2F710qrkfMyCw?= =?us-ascii?Q?B+Ibkj9aKht9KAEosFvaP2Vv/4HQZSJwQGOEMRsLB500jka0NVfgsi6zno82?= =?us-ascii?Q?+rd/11UfLfyk7sYCvnBEZQb6G79xU3pSpbjeLfE5FCIoTjLeyBFMoGvF/PyW?= =?us-ascii?Q?qz0mfTNkOYmRooDUjO1ZIBo0ewo5gZgL+CLH4NR+yilFN/+lRBOIY0U12nRl?= =?us-ascii?Q?VOpqEeFZCOWaXWkXYoF6bvqdta7Jhgw9D8mBtcqjtHS8yYZ3ZEOetzKLa/JD?= =?us-ascii?Q?EJVn8OM8+QSrRdne0J3vRCbV3CaK9YMGFE6xyNF+VC752dexB/1H4gq+h/KI?= =?us-ascii?Q?GDKPVFtu4AS10KdO6Eb4QwEjxrn9J79XGw5wSgk49WcZ2DzYGseNeu+okt+I?= =?us-ascii?Q?eCXBl3ZQOXxAFqt8KfzlF78HxekpBJD4F36F/lp/mlpBn9W8Y2Rr4iCmJ8xl?= =?us-ascii?Q?+x/eOSPf7TD5duITqOWO/cmPppc5hdX+RTOpqfKQK8SabawqQAzhqxiwk8xp?= =?us-ascii?Q?0LuUsBiwUTWcPZSL9SXNQyT4dLxLImB7TWsJLWV4e27SEkPVgwe8d1860pdk?= =?us-ascii?Q?wn9IAZY8zE1qFau9lb63Ti6GZaYdBAWZvJvjkhqun5juLFztTDgQgJryhGAU?= =?us-ascii?Q?p+8GErKspqq1SEBTUJPVihxA+dzIRHuxNd8/33ciM3UsV4VCVOa+4cx95yVB?= =?us-ascii?Q?wAxQVbnOC9uL737SY8TlIadebGETckj3JYmR7qwF+U+icVdHnv/JX+Qbbrjt?= =?us-ascii?Q?doNLwUljMCBKjBjFBR1smI6aVbhTtkqLHG+cr3FThKR5cf5/N6JGfZAC2WQ8?= =?us-ascii?Q?D5k4rLNCsfK8KzAyHlc5Wa5eDo4rq0RlP12KKLgmfQ2B3fFYIkCBJY1Z5200?= =?us-ascii?Q?nc5s3YYBZC7k7kj4LvEBMeRclYEVBnZMLhE0ikME/aI5vDurBfLNpSSDvi5I?= =?us-ascii?Q?WZn8yz3SrR6gDNSGaKrJ8SpYTrlnndXKsksReOs50pJUIjoPkrwM2oHDcIfj?= =?us-ascii?Q?KU24eYdeEyu8dm5PWiwyFw/OZBA/AcwJsIL9hI76AwJAqMErly9egcTqzU5c?= =?us-ascii?Q?KHPOSLQRdVntUF4YDJ/Pb1eR0QGJoHB4gAk9qLXu2Y8uh9mfzH65/JfQb8yX?= =?us-ascii?Q?Y5D3YDTT4Kc8BpPxw4kTDWQZ8+8X6kD4TWO55UvRmwM2U2TcPtQuRFc/9EiC?= =?us-ascii?Q?bVkIV+x/WN1urCFPwpB428umPBvy6Pl4K13oy+ZrrzCGHx3jeTDUrR6xpj3z?= =?us-ascii?Q?7Lj2EcQNqMc+9S1Bv3tLWQTg2X3cpgrCTIjASdhJz0IVOEND5FZOztLW6In3?= =?us-ascii?Q?hrC4F+zcl/zvfVWAnk82FdyIIZJBqV26YL0U9cva3rUgJ+d/y1gJyBcV/J8u?= =?us-ascii?Q?b9rs1ai+QoKo3ztfUT0prfELBocmpnLR0BkfcT6Q5jRg3Nm5+YPMJLq+w/Zk?= =?us-ascii?Q?3BYANk8rhYihaQIORGE7mLNrNyHJs6IrOVnjFBpMCE8JP13RFZ4kpwN5RO2D?= =?us-ascii?Q?/8KAOyYV7qxs2XccC6IN/D1DVEjQGtf/UETGcey7GOxKbXWa9QXPBEAXkKhy?= =?us-ascii?Q?6eE8Stv5UpPSKYMecvxVpdvfxIKL0tl+VnuFwzB5?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: e649293f-07a4-4483-6bea-08dd7376dccf X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Apr 2025 12:47:30.6697 (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: N8/H6OsIHMFLa2blvRzv6Bimcefl81oOxP3d7M6Lc3JINGFruL4qMm8IyxcwpVHk X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB6133 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250404_054737_141298_EF59E446 X-CRM114-Status: GOOD ( 17.61 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Apr 04, 2025 at 12:54:25PM +0300, Mike Rapoport wrote: > > IMHO it should not call kho_preserve_phys() at all. > > Do you mean that for preserving large physical ranges we need something > entirely different? If they don't use the buddy allocator, then yes? > Then we don't need the bitmaps at this point, as we don't have any users > for kho_preserve_folio() and we should not worry ourself with orders and > restoration of high order folios until then ;-) Arguably yes :\ Maybe change the reserved regions code to put the region list in a folio and preserve the folio instead of using FDT as a "demo" for the functionality. > The xarrays + bitmaps do have the limitation that we cannot store any > information about the folio except its order and if we are anyway need > something else to preserve physical ranges, I suggest starting with > preserving ranges and then adding optimizations for the folio case. Why? What is the use case for physical ranges that isn't handled entirely by reserved_mem_add()? We know what the future use case is for the folio preservation, all the drivers and the iommu are going to rely on this. > Here's something that implements preservation of ranges (compile tested > only) and adding folios with their orders and maybe other information would > be quite easy. But folios and their orders is the *whole point*, again I don't see any use case for preserving ranges, beyond it being a way to optimize the memblock reserve path. But that path should be fixed up to just use the bitmap directly.. Jason