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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?gQ5MhAK8EI911y0VxUaeZYeXrHQsIpUyfnCfO1URZcO1Kufhy1sCiBoaKfoT?= =?us-ascii?Q?t6s0YHGniSJIjv78gqhh6v4MMePYTAbF+T2c+WQtfPVy7pbK1sMqSbgQEWWr?= =?us-ascii?Q?nOUz/6mbMn3zQOp786VxrYQ6xj+WE6mMN/5VdewvjHbcM6Z4zEh8KLYqcn/5?= =?us-ascii?Q?bFJ2+Nv3QZjcXdV34FLxGGM6pw3b62Vvu0zEV1xg7von6rp+0UmMqEqf93R2?= =?us-ascii?Q?Ka+Yl7mIlnKzESTvTbwhKKLbwY8RaJuHZJy+rAH6mDR9AOmB2/KypsIcTRZb?= =?us-ascii?Q?eG3xswGEUrWn3UkHLkEoroKTZWoKH1O01oIKvEKxuAO8vVauel5+Pgq4vLCz?= =?us-ascii?Q?rmciVgFUY6c6sIVeREMI4cf0aHG18nf46QXAG8QBC7HUE9kT5JG7y/6K5xHF?= =?us-ascii?Q?IsUpUSsQ83BgvcoSE6ygbdXrN6hLGxhqegNSHd2fWrYQ5i1MQ5dZ2JnIhe0d?= =?us-ascii?Q?T1irMnfo3FjOyBgZCDr407zmW/DBVzVdlrgDN5xReA0PsSKJwL4wyOwnDrnv?= =?us-ascii?Q?kZwMALd7kNxrYYeGYL5ZUqI7lMbbqN46r3pmqEi2bUxM/QTnwfrkLXlGOLI+?= =?us-ascii?Q?H+Nu7ErC9775mZ4fWpb8ayJNF66lXmjMy+760VtRwe1PK2kK6EVTSMMRPhEv?= =?us-ascii?Q?T0wNoKFmtQaDkSalnK2zA6xDGpLAndTnzcc5nr+c2wSFPz36gy3cDkiEjeaL?= =?us-ascii?Q?F/eiRWucv8Qel/S4VmMNUEza73J1WvbzvqR6LZnsrzr0TG7I5KVxgyukr9PA?= =?us-ascii?Q?v3ydUk/CGHCRRLwu0ymOdARoC3ZpcKloc1iz9ObJcruBmAC276lNmGSZqVLz?= =?us-ascii?Q?Rl+DA3vphg4foH9WAJTiFpD8bCnkVk5vuOUbyL1P23BiNd1ErSEp1cwJWxKX?= =?us-ascii?Q?hzrja+O+O14fJnyVR5A1T15TO7ixXjoNHMxzrqpwEV8Tvk5Ste1OUQxKavsF?= =?us-ascii?Q?6O19OjBajAmT7q+urLLsfLyTvYPzPRuoxGSag53VfRcgeMgUhZkopiOArukF?= =?us-ascii?Q?KWXDQY6ysa4bUlcAJTicf1saazdJSw+iTVUyW39fImLM92EvCvek1X/Uj67/?= =?us-ascii?Q?/q7fPSI51NcZ8K5s8IpRKAkqYGuCeCvHW85CcdEmJUWxOEcj2YLWD/oDBqID?= =?us-ascii?Q?Spjj4IR/6iDSSqGnXOXgyAlpqMlkrfiWs92LXvafjBJ/Mi4k+jMt/NBh6oDX?= =?us-ascii?Q?moXDmVR0cgQPB13wCp3UUGcOxx084OXRlVPp9ZsDc0ocRdkgy6hbGOyGYDX8?= =?us-ascii?Q?+Paa5JnYltN2DEnnF7liPMdnryFUrqBRSVNDiozKbc81flu6lO9RreFi0x49?= =?us-ascii?Q?gao3aV48F8tn5GXlgIY2+O4GPUbX3zgTxZ7CKmkPLPfS3w1bkOD5ypwtY6B+?= =?us-ascii?Q?PXWmMPGceG/6Sfo3t2dlbospXJh6cfxNNO+UwYELrXo6gJfN/5t6Rb+r8TEi?= =?us-ascii?Q?jM9VUUlKH7g2ilg5GirVLAysa9sPJ35wmPqlg6Uu4EUWCz95pH1jIiWB4mh7?= =?us-ascii?Q?Va9RZ6lb8w4F4JZxy6C6sYBVIK3sqtHJqJ0U6NKA6TE95quX6qoM5HPN4ZXE?= =?us-ascii?Q?9mVacixBtLGIyziNSkH0STC3ef7T2X6o3KDwUZ+x+xVjWELnLPZmjEqYoK9M?= =?us-ascii?Q?0J5/nuxZSQDBBdneLda1arV/rXY48r17luUWVSyGcOiNa+kB7VVkvzH6BlXM?= =?us-ascii?Q?1ua+cgZIxEf9xxpToz1Fk+6IXRHxTKkW9wAxqlSp00rCO7BD?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c8a4692e-c9ce-4432-7465-08dec7e1d8ab X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Jun 2026 17:49:55.1718 (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: dJuaIsvFGCiNM8oJpz/RECSuF28vuIJAwTc1gwB1nFFYqGtlayQKxTpCo+EShC9I X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB8988 On Thu, Jun 11, 2026 at 02:34:14PM +0100, Will Deacon wrote: > I still reckon you should do something with the memcpy-to-io routines. > A simple option could be to make dgh() a dmb on parts with the erratum? > That at least moves the barrier out of the loop. AFAIK only callers that know they are using WC memory should be calling dgh() and in that case we know it is NORMAL-NC and we don't need a different barrier Other random users calling memcpy_to_io functions on real IO don't have to do dgh(), and AFAIK it doesn't do anything on the Device memory types? Jason