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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?FF5a47BhAifM0dceBonHnH9Jy7mIB+AMS5G2BarWFhHLyV/5hQda0nPSJdb3?= =?us-ascii?Q?dGFmsnfMPH50CdXlr53YSk2uNS+Xevs4gtub+qVlPJHnb5q9kMvW0oynM18O?= =?us-ascii?Q?CxjEq/BvmcuGmQAbWtp49OtHe7ITW+cOALSW63cyT1X/cXBAprmxWobkwgD7?= =?us-ascii?Q?Ri2S96OMB1jfiFxjD61VpGjFB0ZKZ1zhwa3QDgtCDB4A40ehB+VdLMeDV5wk?= =?us-ascii?Q?flaMZCgJsIgm7R3+iBwhe8jwKpnsrnAhG6fdt+0iJrS3ENSuQtS1dmeZqnMK?= =?us-ascii?Q?0lCLkRYyPpRsRBazDAx11FC1VU+v7+UW1dx9rgvxa/EpAkG3gxO8T9wH4Sf6?= =?us-ascii?Q?qhFBSqdGoj3jivo39ic6s2Ufadd1/p2RCT6Z2pnAeeaZJIJZPqwqgfwuWm3i?= =?us-ascii?Q?yz7lx6LBgpnlTqyhlS+DlrK1eLYwTRFzGlaJHNYlLeosjljHMG3BmvxNWXVh?= =?us-ascii?Q?Woss4ui1Q4ClyT8UoO8YqSNCBDerBBg8/Cp6Ul3yefiSWxw7GByP3qOGYh4G?= =?us-ascii?Q?SmsXd59Ur1Z7TMnU1Baui/JelClKyMkKx305FXbm37RHcMbVq1HCNI677BAw?= =?us-ascii?Q?/PVNr83VEI72QLStq6/9wOxJkFgcnSg+lrs0j2nard5AbH1FgmKp55ZKfwfA?= =?us-ascii?Q?LEZr+XThEzqFfaVbI06/yDv9wSuKRRx571tPUMvcZPTNZiLK4U4ZcZwOKUTv?= =?us-ascii?Q?6AXZPNXZQg7IP4aWQuVMrDMT9GAXKytbvCUy8vW87ZFKXjr4qU6VIV6IpTAO?= =?us-ascii?Q?EnoBIiIBXTwJQcBBNuVPStmBsePbeGCHXLm/VeNrOOjlZ7DzHHQgkHVWCfRx?= =?us-ascii?Q?A1m2tPT9KO24LKSrXEaCnVrb7pUS5GKpUzW5mzerS7CnNFbillpu5LbtcG/l?= =?us-ascii?Q?7ePD6Y6LrMpyDhEBaznx6vdUOVMbpg9Tuj4YMqvlO5AaAR6N7l10ytfq3uNp?= =?us-ascii?Q?gPkmTfSRJDYuBKp0bW/bysZPRNWkVxf6uxQ5jClEmspc2DapM+jdihW1rwaF?= =?us-ascii?Q?gooq1OS5yfFpOtNejsonl8cR6/Nz05+Ng5KMMW01xG+0RCK0ja7HC4GkzrRV?= =?us-ascii?Q?Hbrq6YeMQasj4TYu6S35M5RtoQpGs/lKx1acQEh/SQUjUg451X4Oduqyobq+?= =?us-ascii?Q?a/Vw2sEDgfVs3yN9hvGcAx8+5tQYbOC8jV4xYXYnCHOot6DiDYrxaFVRUppj?= =?us-ascii?Q?iTRYxW3rLy3ootEJQuSK/N7pmaFdzWfw/PsfcCqgGT2xqiiOhKs2rrla9VlK?= =?us-ascii?Q?rXu544sbJ9xddWwKt7VHU9k6gJzu8b6KprHtvqOAw5L1B2ftjcSqcMxntMJd?= =?us-ascii?Q?yZAIh31Y6Mdk9XAvr//q3oCd/wC9+olVFnsr5kwpqbVzuOZQ0TS69dJJKKbB?= =?us-ascii?Q?kAoB8wogtAdcSKdE0JJzVNaec0spUelLthGWT9BQLy/3q9TbLZzsKWDL2Pc+?= =?us-ascii?Q?pmjTciTzvqoGGu+sNLkN7p11ITVAxFYdmQgnODWsrXx4yFamePwyNMma3suq?= =?us-ascii?Q?tV8jzsQzX2C+CjeV1xRLJeji518XFOkUQBSPU9Cv6bVvZ1pyE9VuVf5ScXGR?= =?us-ascii?Q?TiP9ss+mFC98B+Uc7qjCbJ/HsSxTGfg2i2yTlUcw?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: cdb88057-a9fe-4436-bdd6-08da5611d9d0 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Jun 2022 18:46:29.6520 (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: cSc448OIFBGkRNEF4AWEIZFWwDhq6wu76mSSXLrkv8w0H1bSnKhPvEuehbpxWuqm X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR12MB4232 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, Jun 24, 2022 at 03:28:33PM -0300, Jason Gunthorpe wrote: > On Thu, Jun 23, 2022 at 01:00:27PM -0700, Nicolin Chen wrote: > > The domain->ops validation was added, as a precaution, for mixed-driver > > systems. > > > > Per Robin's remarks, > > * While bus_set_iommu() still exists, the core code prevents multiple > > drivers from registering, so we can't really run into a situation of > > having a mixed-driver system: > > https://lore.kernel.org/kvm/6e1280c5-4b22-ebb3-3912-6c72bc169982@arm.com/ > > > > * And there's plenty more significant problems than this to fix; in future > > when many can be permitted, we will rely on the IOMMU core code to check > > the domain->ops: > > https://lore.kernel.org/kvm/6575de6d-94ba-c427-5b1e-967750ddff23@arm.com/ > > > > So remove the check in VFIO for simplicity. > > As discussed we can't remove this check, multiple iommus on different > busses are allowed today and VFIO does not restrict its attempts to > attach a pre-existing domain to a single group or bus. > > Please go back to the original version with the ops check in the core > code. Robin convinced me, so never mind :) Jason