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X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Feb 2024 15:30:17.8114 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 3c7f1d84-2ae5-4d7a-cf32-08dc2bdf8471 X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.161];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: CY4PEPF0000E9CF.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH0PR12MB5138 On Mon, Feb 12, 2024 at 08:17:58AM -0700, Keith Busch wrote: > On Fri, Feb 09, 2024 at 07:22:17PM -0800, Kuppuswamy Sathyanarayanan wrote: > > On 2/9/24 3:52 PM, Jim Harris wrote: > > > @@ -677,8 +677,8 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn) > > > if (rc) > > > goto err_pcibios; > > > > > > - kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE); > > > iov->num_VFs = nr_virtfn; > > > + kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE); > > Since it's accessed unlocked now, I *think* this wants appropriate > barriers to ensure the order is observed the same on all CPUs. Something > like 'smp_store_release(&iov->num_VFs, nr_virtfn)' for writing it, and > use 'smp_load_acquire()' on the read-side. It is unlocked only for sysfs read. IMHO it is overkill to use stores for this case. Thanks >