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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?udqpGumafDcqNjTD3O2HxnFmugqCkBrVqBz4qLwmz/BnF34MiH964EH0Ihq7?= =?us-ascii?Q?Na+X32urjpsnBooHftaAPMCJXq0TvbrprICGnxqd91rjBE44M16hOfvqHLQn?= =?us-ascii?Q?EDFo9IsLik7z1ZdMYcPRvf2wv6fVn+dFmP7G6J623UX7HxaGjRZWW3fSgPo9?= =?us-ascii?Q?WjVk6vcqffFTnll9+pKxjdqAOrxpJ7eASckvEHj9wF3kBIQ7iYe8TczC6XvG?= =?us-ascii?Q?l0hZB4AkVAjYiWtk685x9cVITfxSA+AHWGaHS0CaYtpvbnz1I6fV9kIKL1pl?= =?us-ascii?Q?gWuXz9ANB26svfJ5ZDqYtvCnTWtMvINafDKn5KNMuUTczT+eyo2fNbzLevpc?= =?us-ascii?Q?JLWnW0kIGx9EemBDv/vBGNyzdYtJ9563exif2Y+kO5+0leeStaaKaNqzXHbv?= =?us-ascii?Q?3nle+mE1j5HY0cQ3GKSA9jm/nQiUuRwH5iyRViMPVmM59ap6lBx4JJzllg4G?= =?us-ascii?Q?t2leAvL8Y91oocRYaPwh0Q7yaGeDesyV0cGoAZ1QoRoTcYeMpHpppMSKlCls?= =?us-ascii?Q?LdN4ArnjBYgF9Xz8QN7v05SvdqIHMnSDJVmUkwgZzKU3uvfEnCuHJr/PAHZ2?= =?us-ascii?Q?pMKjBJskssYV3FeCImOXVpYChsdaDqSO9wnMRP8GeEcUDaf1wYlPcFlPGhi2?= =?us-ascii?Q?JX9p7CwxBGwTO5cvY4g54Z8E4WeECNvu0kdyB0PTF2XjkPCNbvEKouNxGzem?= =?us-ascii?Q?8H0sP062djUEWbCqYuwTIwyQDfOVU5ah0++AHZQ76z2ldvGs8ND+UzYFCqse?= =?us-ascii?Q?eCY4l+Pussn2MfqLS8WYLua5u1z0v+Bd6igEDHrdTwZPQ1TPgsc9YnLZOAHU?= =?us-ascii?Q?gWrgepNNzNlmHpaOg/NLi2Z2pQBf2pMha6YPpUQ1csa2eTIYnRW2ntjZX3y4?= =?us-ascii?Q?h3GSLOgi+Vvn3bt1UvBJm/QsxOyttnWzuTw6KYDzh2A5rQo6yKRTu7huuJ6j?= =?us-ascii?Q?6r0LX7WVFB0F9PT/JUdzvqUk7zSlYFev+XzasaPoPp0Fel5cUesrtbEMPARf?= =?us-ascii?Q?5S7CaJj2KIYtBWIH1F1+mEnWwM+KtsxXS8Ra7Lx6bhe0m/x0D3gf+HZeGWXZ?= =?us-ascii?Q?ufdNBnLAOWsD8tPStr7UZyLb+1ums7cHK4VTZn4X+Rfu7rRhym3fTGdbRkrG?= =?us-ascii?Q?4m3Wy1YNSaW4p3JdOBNcKQ938Jny1wVtfS7UtC+k9LEUDItiy4D3qlmNK1xl?= =?us-ascii?Q?PUDOQIYB+DxeaX6mLZ4WfXmYC6AjYprRNWHRqOJdsXC++/nLd6eRAOLXe8x2?= =?us-ascii?Q?qXn7EXJNe2qW6WpBjZDx4pE80/NlUvedTpPkQGjtchu7MBXE/9x5wj9TwTRl?= =?us-ascii?Q?ahMD83kFcEFDaMoXfrIaMOW7siMvxzQPEqT7bEk9qvd2Z5r7JAbDkB8iDQN+?= =?us-ascii?Q?XimbH26rbtA9CHJn3++ETtmoJXk/YbogNuM1WE5EqX2StaQu4b0i+RM1b73v?= =?us-ascii?Q?qzuFgHvw4vSNuZfy9S9HBFhwm+SSIhKiNESSy9OVf9KEoISxmv+R8T+0Llji?= =?us-ascii?Q?Me66xam0vrbtgYM8AnWuFQa8MvV1SCJE2p6d1c4lW9by9+f87QeeVAiO73Ug?= =?us-ascii?Q?NRIDQaEDBH6L6DpaXeFwDUWGLDMXdBWSNR6R6aGo?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 775fde5b-d4e4-45ac-59e5-08ddca179394 X-MS-Exchange-CrossTenant-AuthSource: DM4PR12MB6373.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Jul 2025 18:34:36.8162 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: QiXZK7O2+IqobcZWbKnqbFEaOWti0uu64vdeiKviDf1aCgnfjLQeBz90xlBTsQGYP5iZPDI2XCoW8mBno0P9Mw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR12MB5934 On Tue, Jul 22, 2025 at 06:56:15PM +0200, Borislav Petkov wrote: > On Mon, Jul 21, 2025 at 06:11:54PM +0000, Yazen Ghannam wrote: > > The reset reason value may be "all bits set", e.g. 0xFFFFFFFF. This is a > > commonly used error response from hardware. This may occur due to a real > > hardware issue or when running in a VM. > > Well, which is it Libing is reporting? VM or a real hw issue? > In this case, it was a VM. > If it is a VM, is that -1 the only thing a VMM returns when reading that > MMIO address or can it be anything? > > If latter, you need to check X86_FEATURE_HYPERVISOR. > > Same for a real hw issue. > > IOW, is -1 the *only* invalid data we can read here or are we playing > whack-a-mole with it? > I see you're point, but I don't think we can know for sure all possible cases. There are some reserved bits that shouldn't be set. But these definitions could change in the future. And it'd be a pain to try and verify combinations of bits and configs. Like can bit A and B be set together, or can bit C be set while running in a VM, or can bit D ever be set on Model Z? The -1 (all bits set) is the only "applies to all cases" invalid data, since this is a common hardware error response. So we can at least check for this. Thanks, Yazen