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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?6M7YI/xZCefB08iAHdpYq2vV2+Ro3dEk+VbIhFQRE/oJqDzFMlrKpTUYBBB9?= =?us-ascii?Q?Vp1pORNw+bLYb2+1GXODRpYnKJ3a/fXSxUv+V3Z9u0oYZepC46T7Efu1+j9f?= =?us-ascii?Q?YEuF8hB3fst500v8WMdY0icrg/B1tECZV83LtANHlezmlsqIescGOoy8mZVN?= =?us-ascii?Q?cI8+dDBFhlHpBul5sOAMc3JXbfC573k/Ags4Lv3hT38lhAXNxpkUW0vCQDTV?= =?us-ascii?Q?nISjWGNYG4t1c+UdGZSIrA2vbi44ujfJKYklPYseQi2OxDxcRM4M/EL+aqee?= =?us-ascii?Q?P0uI4tIAuQ1f9Ckd3lnaA8HNgu0VeSXS5bxFh1IuEkWbJorvWEY2qHr1/cRB?= =?us-ascii?Q?FYWhGCE5E8N1EIW/Io/fJRft+vyGEI9Ce8nGazM3XRMPRKn6eHT2usZYuZ8G?= =?us-ascii?Q?bb/jrWz5Qyh9sK9Y5wX8pfSdrPUaL29DGORzRrAO9MMIMeXnfjsKo38dc6pi?= =?us-ascii?Q?M2DUXHMMluUGHfnJdJfVVj1hceG6IR8prmhYjZEsvFjLk4yUwwAk7boKhO3D?= =?us-ascii?Q?lR+alThPT9vL+hXCAcdMHCStAgnzcK8UwDVHHCLyk85ekm1omEOGVvN3FY3H?= =?us-ascii?Q?VNdN4jnv7P4SlmQ0xlyarjkwfc9GRndE2bVzd8jCkY73rRBipz7kyoyJDUU7?= =?us-ascii?Q?YX2KsQFsw10fuRx+ypwWBaJ38+myV5/aguwJ80XXUb8qvdmJx9XgXrElhK7O?= =?us-ascii?Q?jycaegJPLovLhKeIDsE86NgPQPrmcGc7hwR1EW+KfspCGQlMZ2bTMIu+aJRQ?= =?us-ascii?Q?szACAZlVslIgzpeeXJ7uxl3njiA/IwORcVMfnA53KlVDQGRSTTHi8vLVAp6B?= =?us-ascii?Q?4PYU+/P1rjjWZ6fanmJPgujHsXdA2yU2KHXD2l+mGy/f6q41CXHDhQ9RhkS+?= =?us-ascii?Q?vkIWKNbRyPhqtf/5WeXXlfJjv+SerEivFHTejCdf+J6U6ekqsSTJS0TKhgd+?= =?us-ascii?Q?3ladXt6YN2cmy7pMhFISgS414NB39jPcuIY0mTRaz4BUhGw/cXbaXDAdccI4?= =?us-ascii?Q?NjNoyeCbLLH6T1IZssLW+YxE99GIfSrznve1jEOmdHqCTulVCxNM8IrLLiJV?= =?us-ascii?Q?IwFgb8Ne5/Tyq5KmFs6FcWE0anxZTE9Imib1D2kHo9sqhbPzO2t1ibeeQUxF?= =?us-ascii?Q?UFQ9Hwwk7DiLUWs0iLay6hoG2QozoZqp2/80tv44NcPfob1AdIBdTG61jpek?= =?us-ascii?Q?MkbnBw0klLWWM2qaKVwPBctHhMUcljJY6knsHyAjyqQKrnnuHZPeClRQo8rO?= =?us-ascii?Q?mYTtiXmtk1g60gsymV/fQSbSHkbx0oekFM+MEa/sZTOj7wZbciIA18SsQR21?= =?us-ascii?Q?d6w8RugDpTNdxpnto6ku4IlE9TwgidrAF3JauPc5Tkpxo46uupCK5nEHhAeH?= =?us-ascii?Q?7XnFJCpvoMV4ZXrWQECIqTfdbexdPQB35k+J6o+IAUJBroMs9sL+kldqYcCW?= =?us-ascii?Q?sHV7AsxmIxGf3GDRH1S2RMHAQo7uO2/7bmiSdkUKxyBoM4zzWdqJisckcoXa?= =?us-ascii?Q?nwG0XapDNYZKVCWHs5t6AwSFC6fQfFH/3q0N6ZAeFnS34Xs5/islzWbZFv1a?= =?us-ascii?Q?2Blr2JTIkSlC+e+dWn+btm8xAC0WJMwpHQ4QPmKY?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0c8b342f-64da-42cf-5beb-08db2ad0c6b6 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Mar 2023 12:27:18.0179 (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: UpWRkEsldG9YKZD4cNEaT5arRG8A57AdQNBntmqZ4VDSbPPzQGQvLSRFlWrmeiL/ X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH0PR12MB8463 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, Mar 21, 2023 at 04:47:37PM -0600, Alex Williamson wrote: > On Tue, 21 Mar 2023 19:20:37 -0300 > Jason Gunthorpe wrote: > > > On Tue, Mar 21, 2023 at 03:01:12PM -0600, Alex Williamson wrote: > > > > > > Though it would be nice if qemu didn't need two implementations so Yi > > > > I'd rather see a new info in this series as well and qemu can just > > > > consistently use dev_id and never bdf in iommufd mode. > > > > > > We also need to consider how libvirt determines if QEMU has the kernel > > > support it needs to pass file descriptors. It'd be a lot cleaner if > > > this aligned with the introduction of vfio cdevs. > > > > Yes, that would be much better if it was one package. > > > > But this is starting to grow and we have so many threads that need to > > progress blocked on this cdev enablement :( > > > > Could we go forward with the cdev main patches and kconfig it to > > experimental or something while the rest of the parts are completed > > and tested through qemu? ie move the vfio-pci reset enablment to after > > the cdev patches? > > We need to be able to guarantee that there cannot be any significant > builds of the kernel with vfio cdev support if our intention is to stage > it for libvirt. We don't have a global EXPERIMENTAL config option any > more. Adding new code under BROKEN seems wrong. Fedora ships with > STAGING enabled. A sternly worded Kconfig entry is toothless. What is > the proposed mechanism to make this not look like a big uncompiled code > dump? Thanks, I would suggest a sternly worded kconfig and STAGING. This isn't such a big issue, we are trying to say that a future released qemu is not required to work on older kernels with a STAGING kconfig mark. IOW we are saying that qemu release X.0 with production iommufd requires kernel version > x.y and just lightly reflecting this into the kconfig. qemu should simply not support iommufd if it finds itself on a old kernel. Jason