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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?gvwFJUn9Wia1rQOFoyM/hIwbe+RoPRkec0qpNm4CfHpfs5h0AnVRCM8eL0s0?= =?us-ascii?Q?8LgfCa6hU2uY1a7vA5nEGFKGl3RVoXMmJtJv/HwF4kylVlB6rPAsuOzdLYog?= =?us-ascii?Q?KewhW7bcX9lBn7v6PJsduKLijpvnDqBTQQAdjVaiY8c+VUjIoMlQ1KA/YSau?= =?us-ascii?Q?Ge9SuS3y/m/Vn0pO43XoHGfUmwCh0lyWekKrtqW/zZUXEoCTKC/xB1kJXdwf?= =?us-ascii?Q?al/tWtP1j031v5EavYEDHm7UMwQS7Y3zHWMQfq/yhbdIVV7jSzpZHBMJsnUT?= =?us-ascii?Q?N3mlH509nUb0+p8uI5CEyMs336nmKjHqd5eQNnPwSNlkjBZ/2iELx3Gf4BSG?= =?us-ascii?Q?Pu/Qc1RbH98TGBoQN16DsCNATcaNw9QknhqX75x9jC98rrUl/ZpjM9damxCK?= =?us-ascii?Q?KoYn+cf0RFVwPvf1QQlG213uUR4XKzqMrHfvPFbjHRTqKMmgMb/LmijLjcbN?= =?us-ascii?Q?yTr/zBVGIrqHAZRI8MrupTjZKL89GCREot/c4M7eqTTEq8Ghnlya+G1VP7ce?= =?us-ascii?Q?D0Cwq52re9oj/km/hofKjfT5IzdVPMrVvtFFF4MCdevs5mg8COXfJ7l6LNCU?= =?us-ascii?Q?hZka56/AaUT4Yrv13sSoBuo/eOyuMzyELWcux63EIku0ip1grxiASXPASVo+?= =?us-ascii?Q?A0yuOKMeKaiyAAx4VER0qTYGY5qYk0UkKrpIYkzoqjQbGRLnX/10CvKkGvvX?= =?us-ascii?Q?XbkTEEIUtwQ0tj2n4LEgdygjd8dGdMUQkUj12Au1G/l2JR8A/BrD5GoAUl/a?= =?us-ascii?Q?PeRylaF2k5MqAdjr99vZ8BbFYNClKaL+4v9a0nIVHrKRmizcDDqFUA9779cZ?= =?us-ascii?Q?cqrHn9+6iMoDG14xmYrVIoAsYrwceZVvMAuMAlBHE2fLkBxG/DoBDT71NbPf?= =?us-ascii?Q?soi02xAZo2MJI8h5uBgURy1YJ+416RFLuCaFjczfcaPx5G0zpSVVteYGs0b9?= =?us-ascii?Q?LpHK95FwaCmXbQgBkoH4eqG8jvDHYXh3bheKpXYvbK2yLawbrURpvl36P2R5?= =?us-ascii?Q?MI2S1cqwEVX9/kOC5WDze1CECr0ivfEhih/cA4AnccRgBeH1FfMYU4yNXvji?= =?us-ascii?Q?dB4M//a69JWsuRxhHRx8QAoVIPpvU98zLpIGpnPNaAOXHgfTSw88sczIZ6cJ?= =?us-ascii?Q?2xWMAT+zhltiL2HKlegtZDmnS40DqsLLad2rjr0kLQ9tpyivrk7lT6Zt64vK?= =?us-ascii?Q?X+vvOAkL9/AnOut/nyEnplItkOKwYhKzuUx1GeUF6mvTNL1NdueWrP1tjeAs?= =?us-ascii?Q?y+ClL1UNJ01q/IVUYZdpGl2O+DnJmwLmOkUynSig4awACjUVTZkX/PCDuORj?= =?us-ascii?Q?RqcjKhUf9iHN3RYPeAUUUi1Zpjo15krpYsoqp5SErmjypqOT/yxLYBuWoukN?= =?us-ascii?Q?LY0pNMxlXxQyfkxHTIkfjQ8yM4dVz32pD5H+qs+bYEOCwIYotBJ+9aVSpGFG?= =?us-ascii?Q?oiJW7ZteWO2GMJ+LETWtzepbVe0yRgAw7QCy8RlkK7nWHb/O16GpOg2Zh3k0?= =?us-ascii?Q?3MJmY7wTDCWORugt2F2hR3kt9cyDwl9qa7RX5D0jE+Qhs+yuTZbdKmEfMBCi?= =?us-ascii?Q?c/N+0IHuU5a97yF+LbaEte9pb3ivYuIPBmRtu2Fso0FRVgYL37Ira0zHv/hB?= =?us-ascii?Q?jIu50Ur95Hj7bLFP7drWQMxq/dWP0DFVkWZVtAIqGQNG7HSYsUN8SdZoFFn7?= =?us-ascii?Q?N3aNtw/87FG6txVI8DLYXtqPVRQtWDHpXUQlBDDYduO8+MPM?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 428876b8-2e6f-4160-2e43-08dec197c713 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Jun 2026 17:44:36.0162 (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: Kf00zUI0Knba8WuNWbcgVfJzaCfD5dCoXh91OOGZYPGMkuY3gFQ6cmNteSqhn649 X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB4189 On Tue, May 12, 2026 at 06:11:19AM +0000, Yonatan Nachum wrote: > Changelog: > v2: > * Zero-initialize AH cache key on cache lookup. > v1: https://lore.kernel.org/all/20260510083035.458081-1-ynachum@amazon.com/ > > ------------------------------------------------------------------------- > New EFA devices don't support the creation of multiple AHs to the same > remote on the same PD. To overcome this limitation, introduce an AH > cache that manages AH reuse transparently. > > The cache uses an rhashtable keyed by (PD, GID) to track active address > handles with refcounts. On create AH, the driver returns an existing AH > number if one is already cached, or creates a new one and caches it. On > destroy AH, the driver only issues the device destroy command when the > last reference is dropped. > > A per-entry mutex serializes concurrent device commands on the same > cache entry, preventing create-before-destroy races on the device. > > Yonatan Nachum (2): > RDMA/efa: Add initialization of AH cache rhashtable > RDMA/efa: Add AH cache handling on create and destroy AH > > drivers/infiniband/hw/efa/Makefile | 4 +- > drivers/infiniband/hw/efa/efa_ah_cache.c | 154 +++++++++++++++++++++++ > drivers/infiniband/hw/efa/efa_ah_cache.h | 41 ++++++ > drivers/infiniband/hw/efa/efa_com.c | 12 +- > drivers/infiniband/hw/efa/efa_com.h | 5 +- > drivers/infiniband/hw/efa/efa_com_cmd.c | 27 ++++ > drivers/infiniband/hw/efa/efa_com_cmd.h | 1 + > drivers/infiniband/hw/efa/efa_verbs.c | 9 +- > 8 files changed, 245 insertions(+), 8 deletions(-) > create mode 100644 drivers/infiniband/hw/efa/efa_ah_cache.c > create mode 100644 drivers/infiniband/hw/efa/efa_ah_cache.h The sashiko comments seem quite serious, please fix some of them up.. https://sashiko.dev/#/patchset/20260512061121.2177521-1-ynachum%40amazon.com I would not do the GFP_ACCOUNT suggestion, we don't do that in RDMA (though perhaps we should) The races look right, the mis-use of the API looks right, and IDK about the leak on cache_destroy, either clean it up or stick a WARN_ON that it must be empty. Jason