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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?J8QKkJy2QYCy5FS4pzMJwSkf86qasYlD1YbuwP/0tChW0XB9p455STNlD8ML?= =?us-ascii?Q?nchRgmdRsfMt2PQVlIxWwCXTlovao0jZzIXYjQn/D/wxLR+skk1KiCXTvM1O?= =?us-ascii?Q?W/ScbN4HUHAwgS0nu01k2cCnl7uGwPTy5CXcJbHiCWs8OaBjYD8+uGqdCwMA?= =?us-ascii?Q?Vvvvvo/2O/ZZXK8js4aHunKE8wx7PfDFX9j1xkQDnl0KvZsOQ/oTdqfkJ6dX?= =?us-ascii?Q?ctOc71WZNxVYVhDVFWzViRbnGFUL62rhCSjviyX53YIs7zIkww+qaGzddfgl?= =?us-ascii?Q?7a4BU3G/szrrYRz3Ji6IQMReBvt5iCYR6jeQKq9O4HFhnnfsXWgWlueW2XH/?= =?us-ascii?Q?ML+VTzQkdvCtj1cFgHphRi4SX6V0MMgt/fCtOHQHmQ8ADZVD50TrHrm5gArN?= =?us-ascii?Q?GwN5RSYotnM6vLvH04pHY1YQssV6bf6Fm4hgeenWICij7/sYgbuQmMdXY7oq?= =?us-ascii?Q?gjzwTJRqrQPZYAXc/vkQAFx23MwC5d1QjcXgh2j7DUEuQ7zG7ya8U5HGfcqM?= =?us-ascii?Q?5BfGDpwiM7GK8y2/LWoZLO2Hvi26DR9bkH6wD9gvizKG+icrN5U4QGTLSPii?= =?us-ascii?Q?wHoqcAJbOuD8RO1F1ewMtkpsDZa1f6AZ/2XEaIG/uehGqNxIhnAre4wpMKqz?= =?us-ascii?Q?sRKspyxTGnm5p6IaVFTS2ZIjA/mI31bAb78XqVv7izRdqiROQ2q8duvi2k1e?= =?us-ascii?Q?Dt0sZ0C3awfwGZYgxR7Di1Se4u/4Sz4FZ4umEtsLG8t7Vvy8pAohEU1qCCjo?= =?us-ascii?Q?0J0lPq91I3+4TP3duF0z+zcPsrR4LkICZQhZaCXXrxMOtylLxEkAkrISK15O?= =?us-ascii?Q?YzWqFtT03BMLFv5DTkWruu581wEr9hIrm5PrYY8rbvJHhV8Z9Wtprxan4XcL?= =?us-ascii?Q?iP2lpBRuZTqOOlvEUvMrgtvU/vMeDx8JhYyNbxXIJKI/EmyP537NMLU6F5DK?= =?us-ascii?Q?+60wGz1koKx8TQaOHAZedT1sSdO5AgDYX3OpQS9XalCgFBYTQLoWk4NalBKs?= =?us-ascii?Q?GSLvwdSImpWQ6OdKRPbYUmgE/6dNLxZS3zJkgIDQ3BZJVdOuCzXRNxDrHhKo?= =?us-ascii?Q?uj5sapoNQj8fGR95wBTztrSDT7/gD5JePZB/uwCD+k0odbQe+SFAXiguY2nE?= =?us-ascii?Q?eu3HlcjH7dHzB7k/6IHTVWgNzoJGJNiAz4w5TV9SIQi8x2Wn8483AY5AjBRE?= =?us-ascii?Q?cQDXj5Wv+6Thm66Z/vDJF5hUa1sWi7mU1ZgrfBkpKLUMyFWZMWayujOWLl6g?= =?us-ascii?Q?NTxccSLbtenB7G7ijKj1zIMwE3m58vd5AesvRcUse7f1Kzxv/fXnqEuV5Sa3?= =?us-ascii?Q?0Lujnk37u6NqSEN1ZdcC2zpNlEi8kcx/WLfkPRbqIfdmunmpFMsl2smHXdk1?= =?us-ascii?Q?craaz5rEUFcHnXF42asVPzOePaZLc8tiuHqdMzLhu2g3zLVoI/D6S2zBNGjv?= =?us-ascii?Q?pLcCqcnMt+3ufnTdGjCBgkbJ/stO07yVLotHYlZaarHKb2y4mAorPYudwJ8A?= =?us-ascii?Q?K6aJD4Xrs0V600CQSNTOzqKf41ySlPGsujfffN7ZjWkzPwl51X9/ltjR0g45?= =?us-ascii?Q?xoSj6b3N7RtWNHO+F2n+cae1g7OzEn+YgMthr+WKMh9o9vc1XhpzxImAw4Y7?= =?us-ascii?Q?vQChkmu9M1pP3PZ72qDBcJYSiz5Kr1E+TnDZZkqa0ElYJdnKV4rCCpmkloO2?= =?us-ascii?Q?6oFSX4XiJ9hZPNxICfe3bnRZDz7fjNhLAOj+SVaziyvD7iPXhvvmNx+d4O60?= =?us-ascii?Q?i99EPQe4+g=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a2261e5e-c3f1-4f83-e019-08de7f6781c3 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Mar 2026 12:12:47.0506 (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: uaXCOkBkQvZstrRCcGx0ce55ONYEZA/gb4qEJgAlKVlpSMRh66dXdeznVDUYcg0V X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB6410 On Tue, Mar 10, 2026 at 08:00:45PM +0000, Samiullah Khawaja wrote: > On Fri, Mar 06, 2026 at 04:26:52PM -0400, Jason Gunthorpe wrote: > > On Fri, Mar 06, 2026 at 08:22:08PM +0000, Samiullah Khawaja wrote: > > > > > But do you think doing the timeout logic without fencing would be good > > > enough? > > > > It is what ARM and AMD do, so I wouldn't object to it. > > I think without any back pressure to the caller, a device will be able > to fill the invalidation queue with device IOTLB invalidations that get > stuck until the HW timeout occurs. Yes, all drivers have this problem currently. Jason