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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?pc/I/jKn9+zmO+S+FIOXNgfgt1BZk5RFOg6TN3ARJ+oKLVUqvOwGcz5wpm95?= =?us-ascii?Q?y1vBoTqsejRwlZqnWda1ZXFY25rcReLIwiel0abNMVDrHE3W6rQ5KvJs9qBv?= =?us-ascii?Q?3W895KW+93iZ0X39HlipjUASSJ6PHVKphSrnlZHUtFMGlyJULnZQMvN5O2CB?= =?us-ascii?Q?TmVlMTc0mHhtAuqbA9M+RSTp7l624Z6yIWHwRzNYWZgQb3MSRhCSrhcaKg9r?= =?us-ascii?Q?yQWgP8T1QDiBkXuid1ydhlVkDJRHlZfXV2D2axIkNvnE1cczOZS/gkVfLCQ2?= =?us-ascii?Q?LViZe8k/Lcmu2gAYIwohhUX01qIZSAmcUQLFbzrAI1GTsBtUz6xXFn3OHdqR?= =?us-ascii?Q?FJ9IXC0C19QHl/SChIkTSm8QyR1kXlEnA0WARwx7c2u4ory5PBuPlPee4HdD?= =?us-ascii?Q?RNtrMtI5neF9KQkOY9yNdOxfuVsMHgE1YEyFWgdbPQtSwYqVZfngE4Vun8cM?= =?us-ascii?Q?H1s8I7CbmcsQY//PR0aQWII9ttl6AVwBy3aJ/9fVK/fMCbaRErz6VdM4AHn1?= =?us-ascii?Q?bdQwfScQD3SKMHA54XFzlleSQgBQIrh7+pj6odg/WOrrj4IRR9NmkwytHaxj?= =?us-ascii?Q?DNE+P1Hb2XS3ZwE3XtjUyyIs2fvKWgI1PYs/GO5DHJ0G6NMD8MAns7gUBKKE?= =?us-ascii?Q?l7AhWrOhGUgjyftXtySkukwjU9kBWc+XaXEZ01dWftgbTrEwRL9bpFhvhgF2?= =?us-ascii?Q?DbtIH29OvLzRaOwIX0rwQv/KX+WSQIAvY7BkUSitjQxGvouQ3jy1p8nneu+w?= =?us-ascii?Q?9KC6xWIKV+By9qi6ANmvtvvLZSSkW8B5yMS797W3voxlFmelDwN7fkz6A+MA?= =?us-ascii?Q?QC2suzUnhUqJY7sBPhkfUoJkOoEkbjRJBHbPom9wuCJhXwxfSPfh0eWb3Q22?= =?us-ascii?Q?Gnhea/eZURKQ4B7disDi4TgciIFz38t8VEUJ74baA7TXMGE6poAlCGUiG5Eq?= =?us-ascii?Q?7SlGEnYBt+3MoAoBRIB0B9MAMAje4v53z0uEDKoYxIxt9YU111oYMWoSFP57?= =?us-ascii?Q?VZ1YrFf0ijUeqm0ag4i90cscL1Nt0ZapVgHp1FtdaRU69is8Hkp4JfbvUV36?= =?us-ascii?Q?mcB7IQIvVOc7C/ghqr4gJ6DxMVKheQvmXaV2w9H1O2+nYQbatXmIRkhpQG6R?= =?us-ascii?Q?ff+iFGrvT+SeypZvJiDPVBnE9JfWkroYDnVIATvNIzM5t+OEhCtYkk1eigVc?= =?us-ascii?Q?ZdJjpWhjIjK/kG8o36f6oQvOMGlat/zVkt3xCUEJK5mFG89qJWb+0DjHw6Xo?= =?us-ascii?Q?vYySeq7c6c5EeBG9hQWK1Qg1l2rnRmvG+ibllxzOmuB0kD32T0dM/N0FkU+S?= =?us-ascii?Q?LdhlrAswfaTfFluDFW8bFc3oe3G4uqRik8mRwGS/qP7G0aW0pxozcOQWRYhW?= =?us-ascii?Q?iT3KqV9HoSTfI/dije3xtWYkhM+FAqZhSE9lLhb1fn8GEsgO5/SWUtSnkzv+?= =?us-ascii?Q?PvUwJXibLVwAFCg+ECw82btHii8j2NGyza6iw9/fMoaCqnMIvaXEV4BpNoC2?= =?us-ascii?Q?dKO266XAwqGcJjIK4ApsDnnpCPzNf6keVTOWWrcetgt4Ti4WUsJF4Frstkgj?= =?us-ascii?Q?QShb+2Y0mk4e311JZdmRQC/qtCUwtXvS3TM2kJhB?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3ccd8407-d032-462f-4b4a-08db4b12413a X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 May 2023 13:36:38.0998 (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: gk6R+D79M1NZF97mZbnBR4UpfvIL1wwuNiTzQXd0mObWcN9ggWH8udarSplUJ+12 X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5286 Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org On Tue, May 02, 2023 at 03:28:40PM +0200, David Hildenbrand wrote: > On 02.05.23 15:10, Jason Gunthorpe wrote: > > On Tue, May 02, 2023 at 03:04:27PM +0200, Christian Borntraeger wrote: > > \> > We can reintroduce a flag to permit exceptions if this is really broken, are you > > > > able to test? I don't have an s390 sat around :) > > > > > > Matt (Rosato on cc) probably can. In the end, it would mean having > > > > > > > > > > > > > This s390 code is the least of the problems, after this series VFIO > > won't startup at all with this configuration. > > Good question if the domain would fail to start. I recall that IOMMUs for > zPCI are special on s390x. [1] Not upstream they aren't. > Well, zPCI is special. I cannot immediately tell when we would trigger > long-term pinning. zPCI uses the standard IOMMU stuff, so it uses a normal VFIO container and the normal pin_user_pages() path. > [1] https://www.mail-archive.com/qemu-devel@nongnu.org/msg875728.html AFIACT this is talking about the nested IOMMU translation stuff. RPCIT is the hypercall to invalidate the nested IOMMU table. I expect s390 is going to have another go at implementing this using iommufd. The stuff in that series like KVM_S390_ZPCIOP_REG_IOAT didn't make it upstream. Jason