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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?iYE3FUkpCH6YfIvEeLUpl7ejmQoIZbXv8kT4nSN3JPQSl7an6inU95m3con/?= =?us-ascii?Q?xA222kX8hBCqqC7OGYHuB6m4mXBbu1WyjomCi3sZUGE2Jdzegh1cZiXSlKQM?= =?us-ascii?Q?ZJLeaHeWalFLQYSD8FBquU5sRp3qlleqiP62W+SlnX115o7elGhBD49qxgCv?= =?us-ascii?Q?G7ZHHlGrsFYjVsmn1ppoBmd7TINJcsNcATrj+tI3qhVBTliiQti6tTO8KnMP?= =?us-ascii?Q?ITIRbwrQhk29F9nfFeuFVLuXev8bH5z9YPYZrqPBaUkdAV6qCzOKF4ar0s99?= =?us-ascii?Q?34vVvtIOhFIJuBXliVyOnVYn/wTzlBc4mavVhoBmrZu1gCZjj/AvFiyPXKm4?= =?us-ascii?Q?TJsL0Vp/ULP/w3pBdcXJTHbulCXv7OaNFQslLgXBSvBFk17RUs8HwBq6iiHZ?= =?us-ascii?Q?8b5TW0O5f0Kr8tjtrQ4Dnl9VUN9GBD2RCEFwTFWAcIVDnY1sbt0gAJlXvWTQ?= =?us-ascii?Q?LAUrf49aLHivDMwcGUwRF1iiRGVRsE6XP1ei2IJEdNH3zXry4+A9n6VXwhMo?= =?us-ascii?Q?zLM9cg2/PLndgNAwnifNBwoqmrpHdIZDgRpmfqpqReHXtRFYS/DPF1yuX8s4?= =?us-ascii?Q?iF3ZIGyCtzeqH2KLWqWwfxbS/5Rg17AxvfzrrXxq21s5mFCSvBjkvDerWS78?= =?us-ascii?Q?/OzlRX7LrRnMvuWas0K9rxyRl6ZeBkwuk4EpiGdf4XIKREpQNXDEX8RU+m8T?= =?us-ascii?Q?8CBqorJrNa1tNt0o9dt2WRPGZTRyRusRRj9nqkQsjYQrdwOFBFV2SsqfNSNA?= =?us-ascii?Q?mxq9LQzcGBn31fzblGYfsiKdh4UJEg/MfxjgAz7nFV0hKntec0X0z4ZT2TLE?= =?us-ascii?Q?aleLyR1wPH1TSitYRRGb1cIrpsGATl5kYGl6SFuyQi/qgXxZR/qiPkkry2GS?= =?us-ascii?Q?hWB7wxIABL2qqC0lJ1c4krVyASA4jxuYfzKmeL339pRN6sUr1Vm7vZxUDmWn?= =?us-ascii?Q?JaUk8cAINzeLyOz+KMJkIfplYs2tyvJJuRX+gXmOmDmjPCNn2VAtn904btdI?= =?us-ascii?Q?G73Qo49uIgXQegFkwljy059RBi4zNSMdv94HO0MJcqjyqGEAnN0UqYpAqoYr?= =?us-ascii?Q?UBzASD67vqyuIn7GvTtxjFHQ4OSk14Sq1eReRx7p+tP+JJdG2lA7qGiXATMm?= =?us-ascii?Q?R7/KL+FmMr1lVhijqmSfLeL0tasWRZg6nJkFRwgMrlYhMxJY2XBD3unXUW9J?= =?us-ascii?Q?8/7keNLG0XXJZT7yzT5uGjgSIwsJGAbpMeDQZKiUHeWVlDeMxYulvuUCZ5FX?= =?us-ascii?Q?4VHpnJNBhOmwIvOqqq59GH+7xes2GR8Ij2pk+sfWIn5AadPOewWuvFhFqsdg?= =?us-ascii?Q?bEnMN8M4DBYgnIseHg47PnPHzUozsuAEDjMNH+nvoraJos5yEQJTcuKhq2E3?= =?us-ascii?Q?SdKjTqOZ3ye7hVHwnim23/Qzd0s7OCFx5d/wfm6D0dvIvdON3IQd6CpgJ1dV?= =?us-ascii?Q?4Vy/+LkdAp1NVRGoogyuGJyrWnQzSIkNRSXnN8ZXYRx4Ln5iUegFhdMcY24Z?= =?us-ascii?Q?qqrQ7YnCgs1i58sfWrwN2Ol7uXiA1ngZ6CGM+8lhREMxCU/fzAVeJMvjjfgx?= =?us-ascii?Q?aps1Vrjt870cv08Xwp5237iFCbz0mFe3COW4eytf?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3cd92ca7-10c3-416c-cf33-08de003d70e4 X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB5757.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Sep 2025 16:21:42.1608 (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: yHX+2f97RKKKMArdJ0v8GvAW7H1bFA3a1VusSzT81ala6Zg3YlCRlJSQED1egMu8 X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB7129 On Tue, Sep 30, 2025 at 11:23:06AM -0400, Donald Dutile wrote: > This is boiling down to an interpretation of the spec. I think we all agree a reasonable intepretation of the spec is that no ACS means *undefined* But Linux cannot work on undefined. It needs to assume a definition because it needs to make security decisions. So I think this entirely a Linux discussion about how we should respond to this undefined behavior in the spec. Every heuristic option should be consider even if not directly supported by the spec. Our current behavior isn't strongly spec supported either :\ > I believe a definitive answer from the PCI-SIG would be best, especially wrt > backward compatibility. IMHO they will say it is undefined. Device are allowed to implement both internal loopback and block internal loopback. This position is useless for the OS, but it is how PCI SIG has acted historically. They don't retroactively make existing devices non-compliant. Jason