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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Zg0ZV+bGX2xlZm9hnSMIrweXsrxerIbh9CX1iyiAGBNG9LO2BZdcU9Acp9B6?= =?us-ascii?Q?W0urUJcqUP8b//CMKCGX+NHEzxdD208l+FVuZ4CKKCvrH1GK953X4Eboh0Z+?= =?us-ascii?Q?X1GeVt6YLJK6MeBRRbh9g0j1CNbvra35QlMwuDoh1x+dp8GOKRmnoMYYVFbg?= =?us-ascii?Q?KsjJ2k41tPcLLcggUP/0uDgmANEr/j8jBL+jNlxGEqahCecq3cgRg5C3ms4c?= =?us-ascii?Q?Y/UGM7Xd344Ec7dAwFudNPCMgar8SCiTBgUcgSyVPIlQSeGSiNYejaGxY+/9?= =?us-ascii?Q?DS6FdWDeEu+Ho1tqXqqH96Q3yxd+na8d5w5nf7x+9gjKOTOXyhBgDRCQrzzp?= =?us-ascii?Q?p0uxV9Vfw0GmGfSRueQvvtF0yKMvMbvH28sCOuB7yZdvQ9VIk3EVejBWky2e?= =?us-ascii?Q?B2soqyTnlQSMGSa9uy0YR/Gc3DzXGG7jViMsHOvhz3T8uYEjCnygDQx5PavO?= =?us-ascii?Q?dm+k9Jzslf9GTxS5Upjv1NeE+MJWrhC5nWvAtNLMeCQzR9+QP3rE03CZj/kV?= =?us-ascii?Q?kpAEBwv4abrhxSCHON1rtOjC269D29jD0W/ERjw7Qn0XQHhXCDl5zODQHUkC?= =?us-ascii?Q?JoJ5ShtLaGqsxMKoEgXH6P8l7KfVmqAGHgl+ZtYvpWvwA6wy8M0Dd8VaBpQx?= =?us-ascii?Q?yC3RIzCpGmceWGpwhJ3+QOiwXTuCQyfGv+Z2EXd/ym1AUd81ZRP6aCdEmb9t?= =?us-ascii?Q?36tHi2NftARpSKUjjjBQe2ynamZjfivqapcZicwTXYtCePJIOAM4AXhM3Prs?= =?us-ascii?Q?2cRu8bsdq37XbV+G7XyOCDJvkxiO+EY4MuL6Z72McZSWd9Rgl3LmzigLxZwN?= =?us-ascii?Q?8m/xh7vMjm5JfOkevYkogZbNgk2M2WYVDfCXq9PyjXbqSZr6dhqYC8jOcL2P?= =?us-ascii?Q?aPe5C2mvS37mGh3sHPMZWiqExJYgIGazycWiKsW7z2VjfUI6zwYVJXuXjfSD?= =?us-ascii?Q?KcvIMCYlWgJHHuAQ9SI98ShW3RC3JUlCInyuGGviWvOXQKL9X8jCf/MiHzaY?= =?us-ascii?Q?dhoPMIR9/roKkvMX1nwnEA2l+92m/SZv0x8+tgvd5PZtIMimINWHiiUW0/cr?= =?us-ascii?Q?4mVnKTN2vVsiLQeUYj5YgNf7F18Ffljol0jUbdqxu6stuLt0+If0OazVSL1x?= =?us-ascii?Q?4MZcS8dMCmkrHIAQwfgbMmHv3Sw7268xxlarEMjUloneSjP+SrrS13/RF5W9?= =?us-ascii?Q?DnyuENovf3K4uoOlsQ3pW5coIaWnn9zjrRTZVZiCC2zh/zznH7uee3KM/jzu?= =?us-ascii?Q?+Vq1COMQvdL8mcvUM1JLM/9I+2XpbU12e1rzDcP6Jkgm2znKTrsIBiZwOeIw?= =?us-ascii?Q?HakR9iL0EMXcoeMb8fDc1/RI282V24aeP9fjq4LvKQR+IWeavO4hr6OI8BaU?= =?us-ascii?Q?qqk6wTueHUj0G6doHJ5f72IC8GuHXneASaFtcXuFjXNGu+bDzsu0+HtrmtL0?= =?us-ascii?Q?MxY8BTeRDXbD0wE30jT0c5L2A0dKV3Vad3nEt6F/qblCGNcdXALIZCSoHKhs?= =?us-ascii?Q?SaHQhG41z1U1cpwwDWEVQGoV80NkrIsrRNe9BJCkZ2Xf31a1EKPyqVsfihhp?= =?us-ascii?Q?yfxp2QbdB2nE3CaOwMQy5U41apEygW8UJfjuUvFI?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4d82282b-ed98-4319-5f43-08db0f7ace13 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Feb 2023 17:33:52.2578 (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: FGXe3mnonZSEa1OyOuuRLB6EUPUYc32bBy4odD2LDi0rIeIFP5isPLTCR0NU+TTQ X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB5008 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On Wed, Feb 15, 2023 at 10:19:35AM -0700, Alex Williamson wrote: > On Wed, 15 Feb 2023 13:04:13 -0400 > Jason Gunthorpe wrote: > > > On Wed, Feb 15, 2023 at 08:32:34AM -0700, Alex Williamson wrote: > > > > > We've discussed this with Paolo before and I believe the bar of proof > > > is not very high. I suspect it's not a problem that the device itself > > > is not yet accessible, so long as the user can prove they have the > > > ability to access the device, such as access to a restricted file. In > > > most cases this isn't going to turn on wbinvd anyway since DMA will be > > > coherent. Thanks, > > > > Isn't that a second problem, we don't know if the device is coherent > > until it is bound? > > I think this is already accounted for in the conversion to device level > IOMMU ops, ie. device_iommu_capable() follows the > dev->iommu->iommu_dev->ops, where for example intel_iommu_capable() is > only looking at the capabilities of the IOMMU managing the device. We > did some hand waving simplifications that was sufficient at some point, > IIRC. Thanks, Oh right, I remember this now :) Jason