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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?dDZlEvXRDsKCXFP6ftkEMdAEK+kxfnDJbNIoja/hsDWxe++HomRyXLZDGynQ?= =?us-ascii?Q?90F4DZsuVeAjEd30F0G2hfdwX5MzDTdjG2wu6ToJBKoobDYrOHXLGYeqayBz?= =?us-ascii?Q?naGX9K0Mw4V2aK9iBrhXvwLxl7AZRce+kPBqc6+ILa2W5zqRpElu37p8/rmI?= =?us-ascii?Q?cUWTgfZvaxTH8/IYmQeTqb0KK6ZfSgbWTnwNSppsyKlkfr3KFc+DzbmKwAzL?= =?us-ascii?Q?VlRu8Kfp7ynUg2zYP77MIjfm0/QWOAzEJrWfB+Z90tasUH8Qv4jwfVNnufh8?= =?us-ascii?Q?vai7UP6CE2SiwsvRW/l65iemVvl8GLc/oMLLTsN0xfACiwe+/wYHxBJps1Fh?= =?us-ascii?Q?SvNK6/Fy7+E6hBC00kA46Abav9HgNUX+fbPWJgfUpwqNUM/eKqC4L6PDRoFD?= =?us-ascii?Q?XqsbxCjK50udnR+qHI65oM6/mNrJptLfH1r9hf+m9YPJWeB/TAZpd1Ak9RzS?= =?us-ascii?Q?3Ou/R6Gpwgphkn9/CZuGKrQ+yvckFy/MQe0b0M5cwFlXly/6JV0Xj3pw4Xw7?= =?us-ascii?Q?rmoG0LERLwF2x2KHcZpnl2YpKQB3IwPGcXl0hh0mHXfPypkQtQ6aOZdFzWAt?= =?us-ascii?Q?K+678ORiUT/dNx8QyeFk693U8QMBUYSo3rXVt0LT2kyXhtB4xqoSxEQKLg+j?= =?us-ascii?Q?3NEA4+4Bapk0OA0V6w5OMLh4LDTkDCVjddCl0IvmKMmBmAkkkNj6mhldwU/8?= =?us-ascii?Q?2KnPfHktxF6yWZXYcQ18u3Wsc3WLHWlXcaGButB5AsrWc3gvEgNccZpiAsZe?= =?us-ascii?Q?FdQQZ2IwhgK0D1dAYOiHa+cUSKsBhG+Wj4zuf755LT/QcW2RRjL6wTX3Q91p?= =?us-ascii?Q?T3ALC1jYxHeIZLn5JRyMlNcZS7B6Qk+Jl6eqjgEASyYvKB7uqK1+uSgmAKYI?= =?us-ascii?Q?kVfZjiOOlC48AcsLDMciKSpasvtvmFf1623ndtYNzmFcJgE6nQ4IsGh+sPrN?= =?us-ascii?Q?dJyUNne2dDa2UCNTs7LOu8L12fh+mf0GeHt1iTXx/ikaACvtSg4ZqqMxHvn4?= =?us-ascii?Q?U9J1p296rr+k0Ootvv7M3HcI5TvkUAcLJAvRoC4rk4EygYf3C6bghVYVmmMT?= =?us-ascii?Q?eRZSznfSq0ZSB/UZhb9WiORZSC2u4cuWVzoccKk6zqhvyU0pmDerdNCv2O57?= =?us-ascii?Q?ntGjKzXpDHhhf9eRihsqcd9R+f8XhAOSQNsxeOo+EPe6TFq1M+nvPnl5C1li?= =?us-ascii?Q?jcDJFNtgd4kksBc/GViKnJRHfBffnxVcY87LyYCGzwqMCop34XIWt0IjRTHf?= =?us-ascii?Q?TZSohcaSW6zW+zh9PypJD1IrKCcEbVx7wTi3CIjJha03Bnp1cOAb3Q/Hp/Da?= =?us-ascii?Q?dEjitB1LKiWpqQhd6B9WUrdaE1QDSlr7kTFUynexhFkqS0qGV/Z5fyrIaR69?= =?us-ascii?Q?Or1i4OK38kADauNthPLB95Y0Z/G270h4hm4Co1AiuH6ASVSMUHpxnW0rkQgO?= =?us-ascii?Q?WCfYt8uXXgXwefORzt6e6KGKNEKczvT2crvSnR2rM37J0t++pRF9NKjsdsGp?= =?us-ascii?Q?dkuoWeYyJThuxvAzbNo8z3i7PRHoXkGGwI0TDrlS8N6S/SiREl4YaWceD/VE?= =?us-ascii?Q?XSLVcKxTSVAuNntZl4JSFDJyV0qKq7KUU43xQeKO?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7557f5ec-28f9-441d-ff58-08da8c2723b8 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Sep 2022 14:34:55.9941 (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: +lZ7Xn0Cz6+CcOxMO36wpDVtxlhWg0btKw0jeDHOB0N5AIQPGyUIkoz1XrKk+KFN X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB7126 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 01, 2022 at 03:29:16PM +0100, Robin Murphy wrote: > Right, the next step would be to bridge that gap to iommu-dma to dump the > flush queue when IOVA allocation failure implies we've reached the > "rollover" point, and perhaps not use the timer at all. By that point a > dedicated domain type, or at least some definite internal flag, for this > alternate behaviour seems like the logical way to go. At least on this direction, I've been thinking it would be nice to replace the domain type _FQ with a flag inside the domain, maybe the ops, saying how the domain wants the common DMA API to operate. If it wants FQ mode or other tuning parameters Jason