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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Hp7A36AMCDk8BMW+TBZpgHXB0nga2Y27XpCYUB2TyWspBmwD6AFT2an7tyG8?= =?us-ascii?Q?6JXAxIjOJaJnHt2iWbKfylOQRoMkShHWxwf8sgC4AgZc5l+jnb2C4O//Aekk?= =?us-ascii?Q?KGNcnQzs+uGZMsGth7aC8vKKXHVXHo93fH8vP530iev73hlXFQ/Ec+IRzEqJ?= =?us-ascii?Q?SJKLHWNGZb9+f3JGEeSBAp5agLFFzWVMP+T16uutrISgqbD5U+AYaXhRbnsK?= =?us-ascii?Q?x0l5DE+/omMJmWqitXdrzYUOwpjG06oMKmBYz30S9+Kn6qd5SJbH/vbYycBV?= =?us-ascii?Q?LPlkU7P24PBeGPlHzEzE7FYtdiKBzvcgw5MlEVmenxdn+f8ypT4kWhKfpcdw?= =?us-ascii?Q?OXA1B5jF3akrzWhI2+V6j0ZqMf0kK2zeA5dBfKs5BOflfDDKSE2CJncbC3Tp?= =?us-ascii?Q?FBxl8JLog79zls6rATq12CPG48q504aHH4Sp+DpeWG4GS5bNMz+FfYr8b+gU?= =?us-ascii?Q?dq04pfjB/MnIAHHk26I7D/qOsOPfQCrzoGuXcxS01y5pTJw9aG0/yus8PujJ?= =?us-ascii?Q?HFxe4mHNhfPRDmmQjCwN4BwUfHzHT1wS5FAbcSwvlbX3KSEZ8eKTUlJLqyzt?= =?us-ascii?Q?jPpur7XJkXNcEChYxaDAXlJRhCuL1+FPjgQCPBB/kYeEExp3kjfVz3wHYttU?= =?us-ascii?Q?nkOs5Ak1jfzdUX0mZTuyzhx4aseJKCsaKd0vPYaKdqgW+g8rGwG5LB7qtIgj?= =?us-ascii?Q?6w88SmjG7wjLIfLkAA3rkAY/JSKCbOOJewL4wpt0mI0aQU/huapoReYqT+bY?= =?us-ascii?Q?BoeEvNU1+/UTOqQUbAqPY6yUop9nCXc2J1TmwDx7FyMIMXn+IxMypnrPhqTz?= =?us-ascii?Q?6acVaRwjqmwi4tIHNLEVgrBB2PAZUn08gWI6KuHhK2CUQzuI8+A55OUnOnLr?= =?us-ascii?Q?r6p6rEckcJGAAEC0kakwMrzE1nZTXE1U+Z0CwaQb646iJ6SHPbPU6yUx70BB?= =?us-ascii?Q?MDAIqMDqHQ2l3MshknjyYtbryrQTEpf+8vBKacadjOYhW7pED/Ql5pSO0ocp?= =?us-ascii?Q?6bY9r+elYB/m5Os1YzGDESpk77OASCDXoOxQK8APg/bo0du+gv3SzQrOf8+U?= =?us-ascii?Q?oS7B7p8zMH/pHS+kKRMa5rjrurXk1Kkd2I2QyOZp8f+Az4AzI3jyphb3KkkP?= =?us-ascii?Q?JeU2XtAABnSdJAwscZ1Yc6verot72Kdg1rMIDY/oZocMuM+ilKGlCyjW5Vvk?= =?us-ascii?Q?f5oUc/8SKMFKacK3vA6lxzSvDBnuRozDc5IwkrEsBBHGpmtQhhYqw7sS5d+m?= =?us-ascii?Q?E+4HZhe3h5S0TL24I8JDbkXmBRpIKSewloffg/hOrP765EmcFcoqXY5AgILV?= =?us-ascii?Q?khloozSnf676+HIstIyrsvdYztmrwcc7SB1q4Mp4FEU0ckzF5q2RnvmS4JIj?= =?us-ascii?Q?M1POwWNiRkOp9TmvLdXMktP6LGn8A12JKhBjTz99qBrXm+kj74W9ZFl3W20I?= =?us-ascii?Q?e0H5JBGA/ihShJSgen9BMSFcMe+RfEhEbp2k2Rxcz1fpn2UgKlxPsg4GLR7J?= =?us-ascii?Q?KXWFAAmYrmbqQbAAxEp22MLQS+lfazuzH6KSfwNA1cI9Puqt5pjYX3DWKV8H?= =?us-ascii?Q?o8JrIls07OkBKnK1expBIqn26DN60vg3WZLBWOny?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3dde1ceb-b753-4011-78e4-08db66b4f14c X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Jun 2023 17:39:13.2964 (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: ISyEunUF6yitILzYshD3sllzXVIxlWJ84q21uAeIuNwEVmak0SstTY9It6MDAvN7 X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR12MB4082 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 06, 2023 at 10:22:14AM -0700, Sean Christopherson wrote: > On Tue, Jun 06, 2023, Alistair Popple wrote: > > > > Thanks for doing this. I'm not overly familiar with KVM implementation > > but am familiar with mmu notifiers so read through the KVM usage. Looks > > like KVM is sort of doing something similar to what mmu_interval_notifiers > > do and I wonder if some of that could be shared. > > They're very, very similar. At a glance, KVM likely could be moved over to the > common interval tree implementation, but it would require a substantial amount of > work in KVM, and various extensions to the mmu notifiers too. I definitely wouldn't > be opposed to converging KVM if someone wants to put in the effort, but at the same > time I wouldn't recommend that anyone actually do the work as the ROI is likely > very low. I looked at it lightly a long time ago and came to sort of the same conclusion, it might even be a negative for KVM as it isn't quite as tightly inlined and lock free. Jason