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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?xCp/vSZFB4xQLERUXeFp2GxdOep8Q14bE/iCzBpJezp2jS9W7YpYRmYcVrHX?= =?us-ascii?Q?9nyoyBducdWZlu2N1y/7aNajDpzAoiezzu4vvdJaD8zi5DlpEfQh/hVav/8e?= =?us-ascii?Q?iE4bKBClZP/XmpmgGFKFHQbbtqyWLZDw4pquz0ow2F81z2Ke5yRkeP9fEzFA?= =?us-ascii?Q?nrEcGVNOrSE78V6pVwXj8ofPCRcwca9JLNT22GnCJyrs0ZFNeWdNIK/6V9YD?= =?us-ascii?Q?yc9Bi2CmPuVS4Qo5Zy/YgoncQVpenbVRHwrlPGrSYbYAoh+F+CckEXHxn+Om?= =?us-ascii?Q?TxRwJvkXYx+OFYnRtbnAM0e4s0bsUjRKIQXJ9QV2CbaU9n2SAH1uLYRr6lAI?= =?us-ascii?Q?FfAFvUb786U1ZPq4TSUv+UolO20Fm2m7wf8rS6W0aZQlRGOkjzCxLYG9Yq3U?= =?us-ascii?Q?dh9LlNG7wiLfTd5d2RKfPzQNZ0r5LUBeAGn3G3E7dwp4OszIn9u4Qw5N/Fo8?= =?us-ascii?Q?r0tFHCe+vZHDVPn78rZPobNKSkr9i1Pg9wyiN+qwgLgKd9YvPDL4TFVNoQ6Q?= =?us-ascii?Q?Jr/zbe/lpKVwd12d/WY2D7XDRPNmfRKcAPwGC0XrC3XfNgaAz37FqSIqLkDg?= =?us-ascii?Q?YTFlP+LKTtJTTkbBEkrRFUEfbPwb6vY5tStNTAvL4ByVRbWJLNIsw/zSEAbf?= =?us-ascii?Q?wM+17dCYtqJv2raT1G20BtIRy4ga67088KlTINzgdGP6vsOi0cVhTexgxx8C?= =?us-ascii?Q?5Q4qAALkNVOYhSlCuWXOWzjjc4bQIGMmBE1RKmcvwnj2uFLrrRRg3WbHCSQq?= =?us-ascii?Q?E5HK8A8C11aLN+9zlQzCe5lzTeAA2LCeYBqz8V/ad9Ry0Qpa4uSC0yXrxUwD?= =?us-ascii?Q?ZQ3met0I1Rsjcax61pJOOdcUfg4ujqnMYGr8cwS1ACWaOjlyOGPFz5f/yeUs?= =?us-ascii?Q?u2ly6PusUg4DrgXnPMwB2rsHmCcmZ03Il0mkyhb2/4bFO02VbpMinfzSUrEl?= =?us-ascii?Q?E6cstzuQAzps4PVWurVHdY0Ma1B2Xj7Wvsh5yla605X/KEX77TCk5BGtKdzN?= =?us-ascii?Q?CEw2oAN7nqzWZCoV72l9wVG6QhGHoSZm0xaitPTTTitXxJZUs5leL7jPhNYs?= =?us-ascii?Q?fc1zH8ljjnbNP4T85cogSFWzUclysYM5eedTLXbC6rdvEnT5eM6gQvFhJ4fG?= =?us-ascii?Q?mNEuDigXyasYwyzMAPJobkV89NAvyTvDkDxXcRsqI5dbcSbOGknQ76NuHEHJ?= =?us-ascii?Q?Qn4eNLDHqNSg59p9Yu7UCMs9ZCVYxpCbIXmlfex3l+lvtOy+ORG6RVxB0Nfq?= =?us-ascii?Q?eFWg7ljElOIXbVj+Ho7Y3F10bfg7PkSp7OAPMNWlkj39ufkFXkxcy6u1NDZX?= =?us-ascii?Q?dirEJTN/x2XFk3T2UPnxRa2iQbZ6fFspL4pB6rhQxF7YXf39H47tc5U/2hue?= =?us-ascii?Q?CKgllmICFhMgKdgYgT5axLjMOfmuTVb6DeMoCjfm9ZzvulkYF/pzAa0f8Bbf?= =?us-ascii?Q?BOVSE/5x0I1CnJMCjxP8LOx+cnWfBWa/qHOCiav1tP4rnI6iZV2w9ysyzv+q?= =?us-ascii?Q?SwOakOKj3Kj8vZQ85rEIUiuty/bkni/2nhM9fHvVnj7zoYg2MrhqhMoXqIzW?= =?us-ascii?Q?XckLLs6IyVECY/LU2FY3Q4RIRfAdedzlL91vKIsv?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0443736b-4be4-4488-a1d1-08ddf70148d2 X-MS-Exchange-CrossTenant-AuthSource: BL1PR12MB5995.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Sep 2025 22:18:24.7249 (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: io3uxfBGE9hTBSJ6zaCBWf9xfEM1j+5B9GGJtEvR/LGkm4Qlcwa+JwPBJFyCugSZn59CNno6lEOie1jAZKMECg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB6626 On Thu, Sep 18, 2025 at 09:42:21PM +0000, Edgecombe, Rick P wrote: > On Thu, 2025-09-18 at 16:23 -0500, John Allen wrote: > > The 32bit selftest still doesn't work properly with sev-es, but that was > > a problem with the previous version too. I suspect there's some > > incompatibility between sev-es and the test, but I haven't been able to > > get a good answer on why that might be. > > You are talking about test_32bit() in test_shadow_stack.c? Yes, that's right. > > That test relies on a specific CET arch behavior. If you try to transition to a > 32 bit compatibility mode segment with an SSP with high bits set (outside the 32 > bit address space), a #GP will be triggered by the HW. The test verifies that > this happens and the kernel handles it appropriately. Could it be platform/mode > difference and not KVM issue? I'm fairly certain that this is an issue with any sev-es guest. The unexpected seg fault happens when we isolate the sigaction32 call used in the test regardless of shadow stack support. So I wonder if it's something similar to the case that the test is checking for. Maybe something to do with the C bit. Thanks, John