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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Ax+TyLf9kJ0baYyxXRZ/Tdh91Lnq5zX4P8CZ0OHHzzVRpIVwDtaNGdt5yctl?= =?us-ascii?Q?tnfBtC8mtVOK8s5s/LcD4owYazOnvQXOjOn6S2Cy4FEfZtEslYzVaOiL73w+?= =?us-ascii?Q?Vibn36uqHWvHkg6ZiKzoFNnoMq25oNE78Lhd2Zm1lbzhiYKTIUmAQC0GuxiE?= =?us-ascii?Q?yaTunHehxvk1Sqd5+KjxEuXxKV3awmetGMmjdDwifLun9AfDxoDyRotYBYCB?= =?us-ascii?Q?t8lAIMijtVNiycBF4LSgNRhrC9VrNDf7VupmlE9Jc10xAlyVTJB+zHTqotWL?= =?us-ascii?Q?/I1pMWeq5Y+gvctMVFZRUbCcZfYLTdPKF4mUhrB9uGAXRTwmJbFY/9C7c3x8?= =?us-ascii?Q?n6pUFKiEqFs/CblxgjAaYz7WecV4LKkC+BQe+WmoIeHJjXr+EKkJlp4z5ps1?= =?us-ascii?Q?LlgqlPP1RniO/9GMfNHJvjHAOzWPq0ObLDbWdQ9AigLH82L4FoFheXL7K3Et?= =?us-ascii?Q?zCn7X58A02KQX1KZ8KKXK6po9at/VRqu8hJmEs+RPWHL2yI/CXAsR5WHuG5/?= =?us-ascii?Q?Pp+9eDClsUMPqC0RgETfWX/vNK1G0SkOauKSkuchAU0yjMrSb5OC1hyjEjW7?= =?us-ascii?Q?4Sv1vViyNRciIC90lDQOpE2cMB+5fKVK5d5NC0cbNPw6vnRrGgcERp7PfKK0?= =?us-ascii?Q?Z5mGNVnJ5mRuZiMc28N8jAudmoXx6wyPuzCH3ov7oayfkDHuOVThbwDrBfr2?= =?us-ascii?Q?66UZtAKhlIVnDui7kBRDT6AFxJSYSWcs8aTmuxjK5FAgbdQU5x93bXvndmdZ?= =?us-ascii?Q?RUKT13ZHtzKhMr2WJE8kimadBfp0ktgEZjacPGCCmiFJjxdkaTbuunjZVLko?= =?us-ascii?Q?GmRTctbj9MTfnBMuK7Q/RTksf1Xtp2BpJLxNGjzLDQ7yalzYFkmqwCS+d2vN?= =?us-ascii?Q?NUcqAhdJHmWYSGWdpgGDhE/R7pl96zjlfHyzxDPpEn0qvFJbpZcOTh/nOhnz?= =?us-ascii?Q?NH4VFX+l+f3AEs7vDfUtTA6ZqgdW5UhC/tQlDQYxM/le/bQEIQuEjorvTkHl?= =?us-ascii?Q?4eE7n56dvl2+BLvsmEtWNyFsrrLn3T1XTm/12h/Wmcful2FVvRLf+3Px+/SH?= =?us-ascii?Q?w/vwUA3aAA9wYdjOI4dbxYzBA6H/oFihwrPwhMpLh55Dsai7l9S+8IgCVl1A?= =?us-ascii?Q?KBKn1VbfGGgcF1zNS4aJHoeo0bZfgNw7fehvs+JSrco/0RrXie3xcpFQQlpt?= =?us-ascii?Q?55kSqD7NlkZmQxLR6QP6FM1S0yV+BRuE7FxXYILYJG7S6thYUSvMfXfpnlyh?= =?us-ascii?Q?EaXiR/pvaX9ALIzSa/q/rjbB1HBWLyJQTLCpXhxH+2w417Se6HxlRlBIFU/T?= =?us-ascii?Q?LoQCZlXDR+HhnkypiweFeJKG+zU4QbeeaqXIXnPuquE2HUBKeDYrkeL+LL+9?= =?us-ascii?Q?dgx1tXN5zBtrHTDNHuMinjcAmKc2At93MAAe+sVGJ89bcFOheE/9OqPxscxV?= =?us-ascii?Q?mBir6mg0YfziswPp7QwurihqqYZxbnuZPWQSGLs67pDG+Yb7kZt0yvfnnddq?= =?us-ascii?Q?O4lNG7YDdhV+HfN/aCWhrfpJeF5FtcAHh4QjDZcVaHVWpHLcNXMFIkLIeax9?= =?us-ascii?Q?11gWwHH32bM4MqDLJ0W0YfXYxiVmLyLKLRzWizr2?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b7267d75-5004-4dbc-6ead-08dc2caf129b X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Feb 2024 16:16:02.4254 (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: CizqCoMAZKEiqCxxS9tBwmquA2565xWFUJOIK/gYv5oG3VnOxHrdQ13TDAVK42I2 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4298 On Tue, Feb 13, 2024 at 03:37:43PM +0000, Mostafa Saleh wrote: > Hi Jason, > > On Tue, Feb 06, 2024 at 11:12:40AM -0400, Jason Gunthorpe wrote: > > Logically arm_smmu_init_strtab() is the function that allocates and > > populates the stream table with the initial value of the STEs. After this > > function returns the stream table should be fully ready. > > > > arm_smmu_rmr_install_bypass_ste() adjusts the initial stream table to force > > any SIDs that the FW says have IOMMU_RESV_DIRECT to use bypass. This > > ensures there is no disruption to the identity mapping during boot. > > > > Put arm_smmu_rmr_install_bypass_ste() into arm_smmu_init_strtab(), it > > already executes immediately after arm_smmu_init_strtab(). > > > > No functional change intended. > > I think arm_smmu_init_strtab is quite low level to abstract FW configuration in it. > For example in KVM[1] we'd re-use a big part of this driver and rely on similar > low-level functions. But no strong opinion. I'm happy to drop this patch, if no strong opinion I will leave it > [1] https://lore.kernel.org/kvmarm/20230201125328.2186498-1-jean-philippe@linaro.org/ I saw this but I didn't try to figure out too much what it is doing.. It looks like a new iommu driver that re-uses alot of the datastructures of SMMU but has a different HW facing API based on hypercalls? It seems interesting, but my knee jerk reaction would be that a new iommu driver proposal needs to implement the new iommu core APIs, not the old stuff. IMHO, when this progresses past a RFC it needs to come as a proper submission of just the iommu driver, in the normal way. I also wonder about the wisdom of sharing so much code. Code sharing is not unconditionally good if it doesn't have a robust abstraction.. Jason