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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?uVf8vtu3uS13KWszVINTB8oR89uWMW/MAu7DYuvc375WRaly/QRZxMp6Fljp?= =?us-ascii?Q?9vLmMnXdOSSsTQ4eggGhMRNHXfSG1s8JwgWnmKVajxlxoKJhrvzwQvQnQ313?= =?us-ascii?Q?09WMOEvbjaTTvkdXoLfqTpH4nufsycEyMKizjCsy3psE61e4GGSuovVXOS8a?= =?us-ascii?Q?+dI+jmdxJMvGTrL0vYO+OeRZXVnaV/dmqoOWrZ566PZN0cqfeOx9AuPOekiQ?= =?us-ascii?Q?cFWNR9QqUxRBXG0NfiSm6R2JkzvMmFzo1ldBSJ/BLzEP5gmwoYQulcyFm7aX?= =?us-ascii?Q?leUI3J70DxZ0o41q43ULTrBdOII5PNBOs4Z0tOTH4Z72FoOS8un+nJMXMRBO?= =?us-ascii?Q?D58qKSX0RrVpHxNgGJAAOtcyLJ+/lDe4tpTYR1YmnUqxLc5Yqy7gQMGyR9Fq?= =?us-ascii?Q?YADxSzdtnJAbOGIWMkGFUbOyOvMw5iwRH2SujiTlBZ6hOoSn7dMBT/7RjS4K?= =?us-ascii?Q?8UwgeR533MLUWvRi/ZxmGqD6/fXRijPyRpm3Bt1XDKjyomsQhNpyoyFzPnwO?= =?us-ascii?Q?TLVdIN0qHiBOKdMTIBsU1a1UvIgroDZdGT22l6/lw+uPNE/xm37SGHqVD8yb?= =?us-ascii?Q?zofXf9kHC3PwyNykDPzwSP+20orDWUSZEBrz+qwWgYyxgoQnbA79VZk+ArZQ?= =?us-ascii?Q?vqc3o6kbe/utROGfuUgPukSKch+hcH21rZy+QS/5FK20aTr+zGKYHwPZ58yB?= =?us-ascii?Q?Opijc7hv4gQi3OPCVu2Q62gVDOlGYiGHIR5QUvtLgKQyCyFvBeRx7jK3xSeL?= =?us-ascii?Q?QVdoI+ZMCeZoaYsNZHp3dj2ZNODTD29fQYABaFTJgU0ynQWvBOHLSiYO0MeP?= =?us-ascii?Q?hbcrRV0Akog3ITSp86beYaq75wjSxaTV/SI5DmMhJKp/F5eBZS5UxpaGRkYH?= =?us-ascii?Q?ndm7M23ZSkwoKlfvqqzQfzCBvFOAxzP6nI6JFlcMOgpfLPTv4+xGg4L4k3r8?= =?us-ascii?Q?CU9EjxQEMrL78Rt6FXhZJD6ZGAjc/4uxto5BZRzPzIcJduR6l5DlGM2Mzk1J?= =?us-ascii?Q?3o/chmLivRJqJeYNluIFU0uTNNVq8w4rdd4cMtOvIuhtSy39z0vJYaNvD/5E?= =?us-ascii?Q?FFGJ6wYbt/rb9MLQByRlOwZbrAVlX98joemXFOGDgt8r/0s2k9rXyrb1ZtqI?= =?us-ascii?Q?E82g39/0HQTNghnXgZD/aDWJUqccJ4uQ5RKObRNeTFKVqrZUkypeUnp/xB9U?= =?us-ascii?Q?6s2mFnkJgcTOOGt3H/y9wrhgKXgsiaEfoeyzRrV2J0So3TAyewBIcQ3urvnH?= =?us-ascii?Q?Dgv1Ap+EF0G6HOJyyomx0PPb7KgtVzg+5vuQXgDaNi3pq6dmeRBRIOauvXhO?= =?us-ascii?Q?qcjJJMHlyzaABo/4/yLfKhir70EdLh90uRKm09ZI71xkeLBGUNlcUZtaFYo7?= =?us-ascii?Q?yjuGwStYs3vxmM+BN1kY+5TRhW+SIfSR/hUfsirrEYCsLxsyRqPm/jAONk3A?= =?us-ascii?Q?5VUPwjOzP5qyhAb9q9Q0MYGgPb++JczELz5/OG03TGDkXqAbBJ9DmuXqiwVL?= =?us-ascii?Q?eyuHE5HEixVhPvHoNYLXb0rjnMKjLlCTm2afI2UqleQVWIaJQzpey+KWTE/1?= =?us-ascii?Q?DEdhwAgcWsJkKuKYnBii0M62fkEXuUW4WUUU6gGb?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5fef147b-43cd-41f8-f890-08dd3412bb37 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Jan 2025 20:42:01.3325 (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: ov9PI1y71iT5xnRzz5VJN2xefeuQLbaWf+mtEXkQXA8x1FyfKx1quUk4CCQRh+tg X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR12MB7858 On Mon, Jan 06, 2025 at 03:52:31PM -0600, Nishanth Aravamudan wrote: > vfio_pci_ioctl_get_pci_hot_reset_info checks if either the vdev's slot > or bus is not resettable by calling pci_probe_reset_{slot,bus}. Those > functions in turn call pci_{slot,bus}_resettable() to see if the PCI > device supports reset. This change makes sense to me, but.. > However, commit d88f521da3ef ("PCI: Allow userspace to query and set > device reset mechanism") added support for userspace to disable reset of > specific PCI devices (by echo'ing "" into reset_method) and > pci_{slot,bus}_resettable methods do not check pci_reset_supported() to > see if userspace has disabled reset. Therefore, if an administrator > disables PCI reset of a specific device, but then uses vfio-pci with > that device (e.g. with qemu), vfio-pci will happily end up issuing a > reset to that device. How does vfio-pci endup issuing a reset? It looked like all the paths are blocked in the pci core with pci_reset_supported()? Is there also a path that vfio is calling that is missing a pci_reset_supported() check? If yes that should probably be fixed in another patch. Or do you mean that VFIO tries to do a reset but it fails and nothing happens, the real issue is that hot_reset_info is reporting incorrect information to userspace? Jason