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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?NM4xF1vySLonoYHhxR/qAFN4qb6ub+EBD+YBFFdqUOVTHe+oPRFKme1jGogc?= =?us-ascii?Q?UqgRlEYoZ2Lwvvq27hw17XsvWrLmlcLvmW/Seq0AJFpu48pef8XnRG3pgkwQ?= =?us-ascii?Q?AEmu0Lkf8rH9TBNEdwd9NKuiwGDNahea3sxf6yaxmUAdpnAUOzrqed2Rq6eB?= =?us-ascii?Q?j3/BzueIdHf7BkKF3sqMPoteUeaTivsz7JtR5sR0NHwCIiQITdp4PmqMQISw?= =?us-ascii?Q?vFw1f8jD1rAWDSCwsgYxUOoDdZUTwc+ohtoeavW8atr/yea+wMpn8PPIFEze?= =?us-ascii?Q?FxXYZSRasxnJ9SHIVz9O/FarN/v+JOh/UE97GU0RyX/wr5Ap/msEEkrbngYo?= =?us-ascii?Q?tSPw0tnNGgH5Wh6SkblMyAvIQ/2EDT2ALjKUJ7iB4ScGzBxI92R9GBc38reZ?= =?us-ascii?Q?5dC2tUdkdvIxIPbs7q4buZXHYGZODvGHwwgx9y+0avBI5pHUSxxrSrXjXVKN?= =?us-ascii?Q?JuJnKIBQ0LhkGGMxoDwtw/xtkTd1l82okS2YcbBA5ZnIs0n5cdu4q5rbB5Xz?= =?us-ascii?Q?Vk8HO3JEF88m8SZa/c1fGWzwJw2Zn9nKAtRj0D81UIqaQN8XHcRZCL7qCWCA?= =?us-ascii?Q?mvGASce77oJOLC2SMH87OTfTfFp9ICoZAkCDsQCrtdtkf92VZ98GI3X5d9Sh?= =?us-ascii?Q?nE2WoUqSEKbL9x4pchACO6XWo/C7/D1zwnONV5WuAbUjjO0xyW5WnMOaHPFE?= =?us-ascii?Q?KLHGJPvBFuxmgQM8IUuF/4T0rEP8qzrcLilXpn2lQUqatfffnfrpDo2nKR5m?= =?us-ascii?Q?XcYurn0sghN4x3pI4CDTYB/PHircdZifRGRWpcNi0/LdiPaRRYTrpO2eOIpO?= =?us-ascii?Q?PqzxvxgJBpxBmyf5nRifNzl8pFUVjShWzIT9ldP/bKFwtdtPUDNdwQDJYlr3?= =?us-ascii?Q?DVcf+tiosiGkRFI17DOGz3nUSNgUnchLudCY3AxDP/XYr9ch6e28bIH/M5z/?= =?us-ascii?Q?YBRYh0fVb4pg+bjXinwASH3PbumoIyX1N5dZmaguzdngcU+MGG+NXUFLL1Jx?= =?us-ascii?Q?bFTX/9ZloKW4MxBNkA4WJ+QdMn2MQxFl0Km1uHZAj+E/H/f9RZ64ju+88NJz?= =?us-ascii?Q?eTzfLZnqsfXFdJuq9AaBVjvqyDr4h8J+fcf0WMZCzXPWQUYuCBGW+zqgcRkp?= =?us-ascii?Q?iTqBUhzP5CBWs3iVwcpZrKDPR7KJU8MEWGNaxdGt2qml52Yvp6XFdJNt9u5O?= =?us-ascii?Q?0mgtmBFPMxNuUufIXYh6NkiTWCJfq9qP2vl/IcfaUqF33MPjv3ncLzMcU3ab?= =?us-ascii?Q?c8UNvWCfwY21p00dtkisw4kdrSX0Mhp2ReG4+jSOFbU8X5sbiLjZFRkk9Y76?= =?us-ascii?Q?D6olbmXs9JONqjqqV2WIOivNanftitucXcS4pbRbwyQa8ojEViGuXLMEZR2Z?= =?us-ascii?Q?kb5bO+/ycsCQM89uS0SBEOLbs8jxORD4sKYHzBSdTd0NjdRi99GIs576q7Lz?= =?us-ascii?Q?C9N6oGDoAEufM9zGmUXMOUle/xEBVkE8jPd6lOTyf+KMzTQdWdJdCN0Ugk6l?= =?us-ascii?Q?zzXiveyzxY3FNKs2DiQysBwFSip8kXGMxjKYqpgLgV18kRlm9fl4Gdglxsgn?= =?us-ascii?Q?VH8RvQwgAVKiWKmhfkEV5k1SI8lDAwtWQSXYcmJIh8/VluLlLFTHY098Wg+I?= =?us-ascii?Q?7xLupe6kFARLSUey3YpinSZC0fymzMA/zcfA9c692yGuZZBEbWkpb9htkD35?= =?us-ascii?Q?BNx1ZpgiOkr9eSFstqTKFIe3psLpKPmLIS4cvPL3yKJenLuy?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 39d33123-1c15-4eca-62ea-08df029ee48d X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Aug 2026 11:49:17.3901 (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: n+OkmGqNf/DJMiMdhRU38kE8CSI7Ph/o1In/dikzMTaiSgBnJxpPl2pCHY55kR4R X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB7687 On Tue, Aug 25, 2026 at 10:32:07AM +0000, Pranjal Shrivastava wrote: > On Mon, Aug 24, 2026 at 03:13:21PM -0300, Jason Gunthorpe wrote: > > > [ ... 52 lines skipped ... ] > > > +/* > > > + * Invalidate a DTE by clearing the Valid bit first. > > > + * Note: Lockless; Not to be used on a fully probed > > > + * device with live dev_data. > > > + */ > > > +static void amd_iommu_disable_dte(struct dev_table_entry *ptr) > > > +{ > > > + struct dev_table_entry new = {}; > > > + > > > + write_dte_lower128(ptr, &new); > > > + write_dte_upper128(ptr, &new); > > > +} > > > > No need just call update_dte256() with a 0'd new. This is how all the > > update flows work, and it flushes the DTE which this looks like it has > > been missing all long. > > I originally considered using update_dte256(), but iommu_disable_device > is called from the early probe error path (err_deinit). There is no reason to do that, the DTE isn't written by amd_iommu_probe_device(), so there is no reason to clear it on an error path. It is wrong to write to the DTE table without flushing the HW cache. Jason