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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?z2oRU32Qrsg+jRUquULAjhUSU5zC80L6UaYcRxQVZvcfiFWaQij0Ni6mbm4e?= =?us-ascii?Q?ckK2dnlKvRdto2oZgkBZUtzd1w25C6+dJWJEeOZbFq4aXw4L1ptFp726Pl81?= =?us-ascii?Q?fmI8oMp3mmE/coMSoMTMNpXwUJbDFwWSUmRzbgSK8STaHpj3riDo/10ZPVUv?= =?us-ascii?Q?TlnGdoey2KOFWXLSRPnL14Bj0M814aSAOFc673xCDAhqkYpY9dbAr/8uZr71?= =?us-ascii?Q?AyTyXkqYo8DeZriTa+H/l2iVEXQQobgkCdP0RsXJj4+SMmbTpwPeSYC3tTuP?= =?us-ascii?Q?mz5dKnjqMpTLwIUf4fH7fH5SXTcwj4+bvVqwvni5WbmkleZjjC4BJM14qsoH?= =?us-ascii?Q?07nZnc1GCLASFS0cCsWBk2gOnkVlyzm0Te0XIOcC/h3YMgehPVeSx1ugqWnB?= =?us-ascii?Q?XDtzjLNsc6mQyIM14lsJijQHmOH3iNUMOuAoPLgrt2PvUKKUXtUFji52aR6f?= =?us-ascii?Q?JDAoaXPYYH3ao9+UEjcQEtPcvm+6rs2a7DoSuuWTF9EPmqXwQW5tPHntLcp4?= =?us-ascii?Q?/pO9ReO0oMDf6UTgixaiUd3b0zRRYSxJPZJB3rr/BpoksIxAMou8xfftbdPk?= =?us-ascii?Q?2QbRdyJWy2UYWeSTByFUDxlSYlJf3ojZriO27XQ/ILOvwBCplmQvJn/VRITB?= =?us-ascii?Q?3hhr9A8/xzelzjcOel2dbkfb2Wb/IvPhNApujJFlAOc2Ac456oIsMFWffPo+?= =?us-ascii?Q?vrNr+0KivtciM/m3WU25aEqpsoyxuJzDvNPNshvRyR+S+8ebYBsJNOhJziwj?= =?us-ascii?Q?/2DWwLF/wW0/gbxZhKPiMLApfaXHcKPIkijbvDRlgJVbT0Ap+s6icwdcFLMD?= =?us-ascii?Q?UUd+OAX3CNWRemISDlJAk9dd+T6KcdW5E432UByiyR2sJ70c/4V7kYPownws?= =?us-ascii?Q?DVG2ZzBQtJl48dWKqmy0igh9b/KUFNUm2ovVAahiDIH68JAOYwlKTEsL0v06?= =?us-ascii?Q?PiiOz44tZk5KK7AQWRzuqYK4Llth7IlccRVDoYS4H7iBdEYEgJwIyDJTozow?= =?us-ascii?Q?62ssz2a+itxzGUN/8DSsBFkdOZEtZ5E6sgfkgulj8CNkdGw2VYvrPOtp/o4P?= =?us-ascii?Q?+Y3G+xeTyMiAd79KLVGHRkDG0/gmSYT1wmn1Q+E2v4rWppNMx/QCa4it8tRs?= =?us-ascii?Q?RslL2VSHBAAci8bU1WODUkbeiy6C2uY1t6wF+IyabQGBRSLP6O3R2wKmw0/J?= =?us-ascii?Q?qiA/XsnI7nOUMlGg585s99lSgAs3fFA66G0hu4RkFZfm3YOAlYEnWU+NmCTk?= =?us-ascii?Q?Ms/QMKL/w8Vqevsirwg9srhnPELhKDeDvKLaQ4LWjVPBpFZq97SfF+r70W3E?= =?us-ascii?Q?xaIgzSjzeTmHnh9Wz/uXpG1Al6nlSfB8Esh3hOmurwukW9li8ICuChXOv45N?= =?us-ascii?Q?hvAaMGIVohbXgrSehTCpUoq4898JZxnDDic8uEz+Bh7KCt1T8sP0111fppAJ?= =?us-ascii?Q?1qgCgfVTr87/WnWwdt3wLVm7I4rN8akM8EbEpUWfnUTOiZ5llO0nR4tmhzTq?= =?us-ascii?Q?2NMDE8CfEagZmGODUJDnOd7fbB4V9UEQfWYoOZ+zJVNDpjXrTBTDh6thSaIb?= =?us-ascii?Q?SgAgaCkTBzAwQ/c2CJD+rHY6qGe/7d2Zwv4ohwSg?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: fd187a9b-7c16-4479-98cd-08dcf8e1e6dd X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Oct 2024 12:53:50.6159 (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: M+rIB0nIXIdG0L0Q4CT/TmXJMAbzddawMBdpkMD8+ig2kwKmCVjXR0GDJOi6PgN8 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB5939 On Tue, Oct 29, 2024 at 09:05:14PM -0700, Nicolin Chen wrote: > On Tue, Oct 29, 2024 at 03:55:58PM -0300, Jason Gunthorpe wrote: > > On Tue, Oct 29, 2024 at 09:18:05AM -0700, Nicolin Chen wrote: > > > I think we'd need the same change in iommufd_object_abort() too. > > > > Makes sense > > I found xa_cmpxchg() does xas_result to its returning value, which > turns XA_ZERO_ENTRY into NULL failing our intended verifications. Oh.. that is annoying, you can't actually tell if cmpxchg failed :\ NULL means success if it was XA_ZERO_ENTRY and failure of it was not populated! Hmm, I might ask Matthew about this Your version looks OK Jason