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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?MH/LN+YT679FpseNdUFxtbpa7ZMyGQfV1GhB7V4wi5NVCw3hukTC0zqtxFQE?= =?us-ascii?Q?p7IEu4INnhbjcPTcbly/eHb499wuPL+3h3MRK7Sgxi+3PxKFAA8urlE+qUfr?= =?us-ascii?Q?sPalSRW/flRs0w9CqoQynr4O3s6loFyiAX6ACKOwvSnkn0IkEM7w4ApsNGzM?= =?us-ascii?Q?K7FukES1GtGTgW8uYR8aXi8D5f+w7DLc6eqwXSv/GEC+XZCmjaBTcaGeM+bw?= =?us-ascii?Q?zDxEw++6visuMPlTaORPx/Q3Hj9vM4awcpxcNanUHftzuTPnUP/bj0ZBWjh6?= =?us-ascii?Q?6gid8f3kjcySzlzehHd9u2/I+sAxvytpJZ94h3FMaxjnKdmgkvqCkbTMjuM4?= =?us-ascii?Q?JCRcUY/HWAy84ogqL6r2lV3etonruriiLj+aRyWR2lZTaXZSx+CMSALaCzdd?= =?us-ascii?Q?oeHifxw1I4Zswgr3IukZnjpbcxI6rPo5TaoJBO0yXQjmrfhxbuu9FBD0WXIW?= =?us-ascii?Q?UetKueksmoxTRCrFFS7m6m5Xw8wo/p1wPzLZp4JVRElmqmpCDzwkT3IGr5NU?= =?us-ascii?Q?HZaiIazLKqjhgZC0FqRD/DRNIVq5c0mB79B5nNb008STSoHeqwt4dL1LdSKn?= =?us-ascii?Q?SVzhgcVGLM6gm8nJuJgd6Sa9f9TGXWtrkQPTRwlG7ze4nnTD3WQhTNFC+vUF?= =?us-ascii?Q?pmQ8jzAJRdOtDtSOgibzfKos3fZwAm1ifvkb/QWh6Ih1QKOY/TU+TXg9dru0?= =?us-ascii?Q?jUIwrVefYvVBgmSvGbj3cgVKKOV1gK/iUxw5YXYmNiC1q696sNvqck9rLdjx?= =?us-ascii?Q?PVvXyUwSweZQn3R1QwA24b/pHFMczK3Tw1vVgfIl8Da4kV6Dg39brjY/CY3x?= =?us-ascii?Q?oQwChAAb3pnhTGlP8q2LBCcU87r6nT+6WwVq33qPZhSKwijHhs7LEjP4Y3hJ?= =?us-ascii?Q?bmXAhh4Hd5p7TnmFryGgsyKMzLCPIfROuGk4+Vct24R8GjsZisleHnrnJqa+?= =?us-ascii?Q?AWJxeWBdBuGBVfkOx1bG/uevKq8MfpbwM3ThlP9VMiDpXA/TjgVk047R7MxC?= =?us-ascii?Q?ZFnO862qi2x5Ks9pkvGoVEGY+ekwkWlzmckdRtHErZgMqTI6VowtXONlayi0?= =?us-ascii?Q?xKcal+aQ9fFv00t5DHQYSn9P89QPbRtgaS5FX7mtYNiP+G6ptryYxsaSKbw9?= =?us-ascii?Q?cs3cuRsQVefwWqF48lfWo/Gv1KRs/HiELwX2khqhRbx4bbjVH+jnKcd8ADi7?= =?us-ascii?Q?gxprsV1Glfd62A3I19ww0Vuvot6j4crY6ugiAoxF6pd5aiVSfLI4qm/IUdcY?= =?us-ascii?Q?oovrB5bIj0gmD2KzYboRsnxl7/iB1s1vHJP8Tp06HFCH5TVCqDdjPxnMECdQ?= =?us-ascii?Q?VKWM7ahpsotmv4/RoW0PnBGV6Rrt6Y9om5DWH+EySs3HAUK4BG3wnkc6IHLm?= =?us-ascii?Q?IczDQ/x4FNjVGIWWT6qpeCnB54sSfnwgjqVXt6YKVsEkpbELHafQHKP3MhLe?= =?us-ascii?Q?dkMEf+VqhBUkpfvz5XI3XJ6T8K+Bl/owzoEA8LkkxZu8Xkt6d4TcenJiG+Ij?= =?us-ascii?Q?I3PtCyHHfRxyoB7gdupX04Icykkl05L/3BBAwL19PuU2nmBApu29VDt2nsEz?= =?us-ascii?Q?2E5bLfF7p8tgE6B44terzgsQsJ9wsjk3UAbxkpNQ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: e09a2044-3c69-478d-ec78-08dbbb635f4b X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Sep 2023 11:59:27.9469 (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: +b2JaZcynJ9/YIAl2WiKON1alJ95UCt/9h9jAKti1d6C8uZNGKq5emzi5qKHAIJe X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL0PR12MB4881 On Fri, Sep 22, 2023 at 10:23:26AM +0800, Baolu Lu wrote: > 1) PCI device supports ATS but *no* PASID > In this case, ATS only means a TLB cache in the device, and it does > not make much sense to cache the 1:1 mappings in the device. Even > worse, the ATS translation requests could probably cause I/O > congestion in corner cases. Therefore, the best choice is probably to > disable ATS on the device. Nope. We have important use cases where ATS must always be on. :( You might make this argument if ACS is also non-isolating though.. Regardless I think we need to get into a position where the iommu core is deciding if PRI or ATS is enabled for a device, not the iommu driver. Jason