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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?kfAe63i7Pma9S0lNS75G4jKHZ1z0mRAqimj5vR1KsrS4cu7zCktC6cOPcQIv?= =?us-ascii?Q?SjI3YPsU8qu+sq18C3tTQV+JZIMX/Nw5FPg3J403bVlahOEDrOqOzSpQKg69?= =?us-ascii?Q?3PN0uA/Hl8QaTLUIvpl65/uTfcD8nb5Ij1e9ThfrL8aBFIVLOJfLJNdI36Om?= =?us-ascii?Q?eFv8pPOZi+gi4XuwcrYynJWNeoXevwiThmD4EHCN4CKvqJB0Eki+0oaRWWgf?= =?us-ascii?Q?cAQtSAqU9K4BabT0FXPeTEhq9wAhfIqn3Cft8b/QzXIKuPWf4gI1Um7lRxmd?= =?us-ascii?Q?bBQWuoHF2xzWrHY8pF05Zed/YvldGybFqI3/ktnTHGOP0I5FeZaqrzMlfVUv?= =?us-ascii?Q?n5plL8kfm566rh6j1eUrBvkPf9K/vl8gbeg2WISEZi4h/m6RrRXvRFZspWg1?= =?us-ascii?Q?mjTxs0Xx1pEu9nvqPcuR+BdNrkz6nblmSpjZpAcnjKRv98gpgLNc/R2uWBG3?= =?us-ascii?Q?eViRRM79WTioEoznQ0jETSB5Il1jstFabY0YQZPdu5DK9ptFiPL0efCQrspb?= =?us-ascii?Q?o2orpBikJXEGut4rLUbmq/V2MeWDP5ATuXhXeYFw3x5b6pVVRozqMMpJVO3L?= =?us-ascii?Q?+OLRtusZvwYNM7maublhaAqBycIzJWbTTAO8Jii6u/k37WKMe6qxkiHe4a5I?= =?us-ascii?Q?WL3PUuf48CJSv81ZSW7iGZIIgPYywC6sXkBk0Vp1aAEtvdoCPVovoDVasN+2?= =?us-ascii?Q?ZSvbC5kK3A7NVSdu6c+0FFicwxi5mluntIm23SbRuQcY0axSAn8cjXqwtlei?= =?us-ascii?Q?F50RYqtWlSKoETe5s28RLwP/qeDZgm2LFoynXGXrC45m+wukFBoQKJ5qgYjM?= =?us-ascii?Q?gifcwJR2viGBcfK+5u7rQif7hgsEBZ0pxDjIEUpsQijUI7Y2pnXko394Ndiz?= =?us-ascii?Q?Ud4oU3mgcGlMJIa1GdY9E2pGOQDmustvMXOcMj5iSZacEixI8bzgFYgwx7lg?= =?us-ascii?Q?0IhTDb0m51VFtYoi+KV7zRoWCmJxZjwBv63Eu/doQZCOnbnNtSOzeI+oAawI?= =?us-ascii?Q?eNOTEEfRhPpS0w1ua6qIGIhvmqb2NdlMEgekaVmjKbIEaDvsq8TkqDkn1B3V?= =?us-ascii?Q?rDeez9SA8NmRtDgg98avXOtG4sAfnSWFP+hMKUUhwjDvjVtMb2cf6z7ME6S1?= =?us-ascii?Q?DlUextKUluGRCrvQRAoi9jxZcZQyPB+UOt4sa16JI1LwdfevGiBGY/kFGlif?= =?us-ascii?Q?CcKNH5VsNK2aLPKUUn2HcfD/elU+L2gcyTvy4f90NCR29pJvUE7DQkuAn024?= =?us-ascii?Q?iBbPPfRKZfTQVofhu+7ndtkKcTkSTzHr9l4DNiFEBglsqLJqwY74H2yHBR3K?= =?us-ascii?Q?43rnF9fZliALOnXgpr1aQzIbllU426TJu+RAqhq1+PjfrWTfZ0sHCDUgKCBC?= =?us-ascii?Q?KNJE5RQ2Wos5gsi37FLvoTu28UDwT7n7H7Zk7NYxY7a5G3+VvGHBTmo4cGFI?= =?us-ascii?Q?EiZifo2NM26cqlHBlpYFv/yXhSxkaEa5IKfRBZhDtbS/I1qotuBF9xFMHHiM?= =?us-ascii?Q?hIjdb721ormzAKV75boN/lplkYVVOsJu/qSpsWhBcF8Hx/mN7y6+fMgRxwZ5?= =?us-ascii?Q?lFb6mTprk0t9J6GUbx/GxDZv+Nrcr7dmS2n4sa4z6QeEg8baQFWyXRzfw17I?= =?us-ascii?Q?SURQg34jzyUk2qbkw7Nyacocpk7nO7Doq999DCZMoZACfbPImpJ3Uwxbi0xf?= =?us-ascii?Q?xz+MQJVVUEWR+wr3Im2bXDTMRkYbAhMPOS9wjwCweOXbkdhGsASsT+ZZt4Nl?= =?us-ascii?Q?rQ0/1mp0Xg=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2a081e1b-a000-48da-5c3d-08da28641c24 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Apr 2022 15:39:26.2675 (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: fccPEF2UuJ35KnZnMBJwb3Npg7/PQ+WsZs7pMbTFXpj2zCtECzvWTZP7wRbOxEhK X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN9PR12MB5083 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 27, 2022 at 11:26:40AM -0400, Matthew Rosato wrote: > > > zPCI devices (zpci_dev) exist regardless of whether kvm is configured or > > > not, and you can e.g. bind the associated PCI device to vfio-pci when KVM is > > > not configured (or module not loaded) and get the existing vfio-pci-zdev > > > extensions for that device (extra VFIO_DEVICE_INFO response data). Making a > > > direct dependency on KVM would remove that; this was discussed in a prior > > > version because this extra info is not used today outside of a KVM usecase > > > are not specific to kvm that need vfio-pci-zdev). > > > > I'm a bit confused, what is the drawback of just having a direct > > symbol dependency here? It means vfio loads a little extra kernel > > module code, but is that really a big worry given almost all vfio > > users on s390 will be using it with kvm? > > It's about trying to avoid loading unnecessary code (or at least giving a > way to turn it off). > > Previously I did something like.... > > https://lore.kernel.org/kvm/20220204211536.321475-15-mjrosato@linux.ibm.com/ > > And could do so again; as discussed in the thread there, I can use e.g. > CONFIG_VFIO_PCI_ZDEV_KVM and make vfio-pci-zdev depend on KVM in this > series. You only get the vfio-pci-zdev extensions when you configure KVM. That make sense to me, I'd rather see that then the symbol_get/put here Thanks, Jason