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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?4X9LW8DFkhJXKvVQ2ht4SyF1Mv8wGNcpaQDoKT9vZw+cnliy3Qhz0OgRRlqs?= =?us-ascii?Q?GPzr4YbEt/bNWlIWuH0/SeVVUmTWa2zuZMoRK2Y3sMiUdoNBvzuU2wp7+l1I?= =?us-ascii?Q?Uiv83xjbys99FaptkogfASlVXqM7HRqdTeSVMQjpcyCO151RRVlJc1EYg2ZR?= =?us-ascii?Q?mSFQBaWNWfEmRkWcEMdjnnud/iFpDs75Zy6ERrfC90JcE0OUr3IVF0V2dJBc?= =?us-ascii?Q?xbm+g/wIw1Nzrq1ygnfwlLf85J8ruE8UwM7M08tqiYmQVTjUi7W9HOck9M09?= =?us-ascii?Q?sPeXHfdOYJ92BxYCOSbKamJUYDSzFRCiJu4FpjWcFLEbqUaVwqu7hFD0GYFR?= =?us-ascii?Q?0bElNkYzYYeG0ukSN+K+gtw5mhckxuaz6/VIRqOIe84lZj9BIIQeYktTcwQ1?= =?us-ascii?Q?kXdRrmTCBrxCXAd2nB9h9qYaJ8C6be39+/WNeoc9IuWgIlwdB+WbiMnGiBiU?= =?us-ascii?Q?hJVVYjelpdZumsx7oA8KsJnclOyp0RFHT71Wpf5I2npUN5WKm43FhtwVTRbN?= =?us-ascii?Q?shPTyOGVLPYEkE+mbILgawQZ9GKCPA9YmAUapPlFSS1X0COwvQqYOXOOVrrO?= =?us-ascii?Q?l49DEhB0e0p8VA6luNSsOBMybCKNKqqf9rCHgOQTYKMmn/eE+C5D+M044waS?= =?us-ascii?Q?M4MJx4YXY0XOmhUfD4PiaFuP/jf9YFq0L5sF06y5M5k1odLZdAjKNp5i0d0l?= =?us-ascii?Q?67F1A0hLgegc/9/n45ef+2ncnxL9pO1a3jcl/NEHPQKpjywG9jq9Dv5WVEs3?= =?us-ascii?Q?RdWd2xSPzy6pDyyHQa8BZWuQ6c0XSYkc6L+o0zwoA4Lgj/pFD7Uq2sf+PU0r?= =?us-ascii?Q?TGnDqFO6Y9MiWOlIQN3WmwPqWGF3y1zBOx/nWjRcoHqFHTtukJ2ZZVEQbQCX?= =?us-ascii?Q?VEmpBpnPyAs18kPYtn+ecOK+JyVZ/TeZma5wcZT6YwvefAlPkSpTdlAtjQpX?= =?us-ascii?Q?2UOlpo8Hjb8NkEFb9sVDDtlYQ8ryxIragnaNHi5ay4gAWI37kbI7b1Ry5WTc?= =?us-ascii?Q?brEAwJE0MMWw5jUfefirMOb4u8M+nE2kv1+urpzxYv1fuI+UuVRgOFnmd4Bo?= =?us-ascii?Q?2yQBRCulARQmlyWof/57KZY2nGXv70vjylscXcD2qP2raQUivVDJ1d9sw3H0?= =?us-ascii?Q?XDss6wjSu15yJyP1CdcMoBL/oAOqlsCNDheYr2g6rzKGc3lrfl/ryN4PspB6?= =?us-ascii?Q?4VKm04Bu5PoQtshCLdLqhYeUDa1wn5/EjRNQIlYZSYfxkCEkpVoZnWjvEVwI?= =?us-ascii?Q?saXB7t8JxOANpf7ONVmM759aexIznez28XbrzfosYamY7ipHK+Jwj2yTl3s9?= =?us-ascii?Q?MnEnQD5B77MMCmhbnZ5SA6jiLbkURsocKhLmJ/RJXVLnZjWhdzgBXqlf+6DI?= =?us-ascii?Q?Py45l/d16ZRvQ7wGhpNSGkMSGeLlfkFnX2G3z8w1A5/Lx/DhPJQZDoCb/LCi?= =?us-ascii?Q?CrPiv1c3SXn9L7THAoTcZC2aTZrAzzwGb619jhmGV5UQ15bQRuOyXGBsvElq?= =?us-ascii?Q?CBRFwF+mJIm5/UtVs4HJ7XzkPCUzFnTMdGjvg7qciIPrptcF5X7E3VdncqlA?= =?us-ascii?Q?aLFTFlLIx9wBgMls+Lg=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 844bee32-3829-4ce7-0df8-08dde66327c0 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Aug 2025 18:46:10.1739 (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: xF7d69NSc+bha40z7R1FUAMmZ534aeRpO+Q0748YkbY+KMAfWnivf5VQzKzmSSyW X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB7846 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250828_114621_184264_E8A01D6C X-CRM114-Status: GOOD ( 17.79 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Aug 28, 2025 at 08:08:13AM -0700, Nicolin Chen wrote: > On Thu, Aug 28, 2025 at 09:51:49AM -0300, Jason Gunthorpe wrote: > > On Fri, Aug 22, 2025 at 11:50:58AM -0700, Nicolin Chen wrote: > > > > > It feels like we need a no-fail re-attach operation, or at least an > > > unlikely-to-fail one. I recall years ago we tried a can_attach op > > > to test the compatibility but it didn't get merged. Maybe we'd need > > > it so that a concurrent attach can test compatibility, allowing the > > > re-attach in iommu_dev_reset_done() to more likely succeed. > > > > This is probably the cleanest option to split these things > > Yea, that could avoid failing a concurrent attach_dev during FLR > unless the dryrun fails, helping non-SRIOV cases too. > > So, next version could have some new preparatory patches: > - Pass in old domain to attach_dev > - Add a can_attach_dev op I wouldn't make this more complicated, just focus on the signal device case here then we move on from there Just adding can_attach_dev is big series on its own Jason