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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?BkQSp3jvp6S2WhcoccRF2vUFCI6K6lX3rGAd6tOMFsXjU9QB0Cf1m3phW49z?= =?us-ascii?Q?vMc87zn1yBtC/Ct4kEuT0J8XLfGd7WnXBHvvhHki43rAUWMrIj4Y1jSWQBv9?= =?us-ascii?Q?hwQxUM4bwuyjphslTMLunnbbgitAoK6gnAgpHItrw9NdStChXoHuZBPydtV+?= =?us-ascii?Q?X/DrR9w+HDsQE9D3GIM2nBklGXTkh8+ubgZqds50YlHEHG68DfBysHQeaQwo?= =?us-ascii?Q?QIvRsYxJRZL2z5Dm4Afdr5uVL22Gvkj65eEMM5CXBQyMiPkRI4nsxdvAg0wj?= =?us-ascii?Q?08Hzp8Q/hauRt52AGMRKG0tXugNZlL2tuD0+RkGe5DFtb1+e7N/MBP7Ugw8y?= =?us-ascii?Q?q8+2l+r8pHwGc9tPWrIj7adEg3vm1ifcYzbk5nOdYyBudH3Tl52Ezl/eJi4u?= =?us-ascii?Q?fE5fPtcHbhnOppYTOeE5zU6dyuNcplShA5xBfmG7mfi1A2NjHuo4LW/dlref?= =?us-ascii?Q?ovTanqYCot1m8pHt18UfMUcnRtSiP8TO4IJYNNPB1f9yqTJva/iCl6D6qwbf?= =?us-ascii?Q?NuhvciXQc6+sKAXe10YLhtaNC/grX8wFyZLqQZ1yVoRjUMVFm9TDqbtJPuE4?= =?us-ascii?Q?7zcovpRc3v64A5J3bsapbsjWz9f1RW1ZDfmAxQYHb05OY/rHeJG8UQaF2Khm?= =?us-ascii?Q?d++xngYOT+/t9nxQQZwUTWr/KQ/0iPViT+Tyde+plBEARxLpeMKIXoLBrreb?= =?us-ascii?Q?f7SUD+jw9+IZsV8A1mW60OuVO36+lUo/mX3o90uYfchm89lSgdVNU2UjFgox?= =?us-ascii?Q?Sbf0ZwjbVMx4lAbYbWlXAGbJddws+6gw3tQ+LEGwR+44tw0gcHw1stuTYLX6?= =?us-ascii?Q?psnmaUekcwE0ekGQXbqMXw7sxpOXurJ9MZjB/NmGUhIVQsGNgW9M4X2Gq/e9?= =?us-ascii?Q?leE2qDhh9KDBPr6PExWth3DYkVb0YdYYHz92+NxKxNQM91Wsvecn/N4InSsA?= =?us-ascii?Q?/KmCalSAUxd+z6ewTF+vNIZarPGfkrhnu1RgL6ymH3axIyL69+LkZNqWCgKu?= =?us-ascii?Q?6EDF7A2/OSMQ9ct11h8WfP1YBCyylnbFizRi72g+yfxX3Ta4DFIZMLd9CuTZ?= =?us-ascii?Q?JKrT9YCVQ9kLrMut+QU/nhjDZpNjC9caydqkeUk0Ox/aICgFQOGPzAjpOVc7?= =?us-ascii?Q?k5scUrEEPDHcTVj/CRSfh3FJEkbgauLh9B/jNOphha/qAdQh6vA6b2uQ5aa1?= =?us-ascii?Q?eA1UDWNpgtpUdVGrLxzTAX+1lKII7wH4N7UWuVnBMu/FKOVGCGxIvnyuvksb?= =?us-ascii?Q?iX4HzFmojBWZhdIsCdldV/LzP/BA4AmHoCWhDxspNWkcj8RzeOpv7lekYpmi?= =?us-ascii?Q?ooWM6E1KI/WhIDoIXNIWu1DdKYfXjkAaGPBDTSn6fTKRrykdZ/2OYk27A1AI?= =?us-ascii?Q?peEMNhP0nCR+jH8C9r/cU7TfuTDp/D9v8f86k0Tp8Sj0GCTQfVAbaouisr0f?= =?us-ascii?Q?wbmC7iilz9OBdAmRWcqP9T2qtrDMUQCtQazk7MuAgD1gM5QghOVyxhe47QeH?= =?us-ascii?Q?ZcjUJ5pQR4rnOSEvhst68vX908AfhL5eaflQthZZSsTayFrdzZyzCVrypBfI?= =?us-ascii?Q?/g1AGJD0Pd9cHe9EHaZleDfdvUSq+owoU8CsKqMG?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 47628e0c-ddd2-4268-5ad4-08da9b3c5b67 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Sep 2022 19:14:36.1595 (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: JxWZPVVaHYjbAEUP4zUkZXGaCE5bpRBj8ICHDCE/6HgtvZeVA4cS3oBp6mwoSMJs X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN9PR12MB5161 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Mon, Sep 12, 2022 at 04:32:09PM +0530, Kashyap Desai wrote: > I noted your response. Issue is possible to any RDMA h/w and issue is not > completely Rejected. It is just that you need another way to fix it > (preferred to handle it in iommu) > We can reopen discussion if we see another instance from other vendors. > Quick workaround is - use 63 bit DMA mask in rdma low level driver if > someone really wants to work around this issue until something more robust > fix committed in upstream kernel (either ib stack or iommu stack). That is not quite right, I said it should also be fixed in RDMA, just none of the patches you are proposing fix it correctly. You must avoid the mathematical overflow by reworking the logic. Jason