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Sat, 22 Aug 2026 11:52:00 -0700 Date: Sat, 22 Aug 2026 11:51:58 -0700 From: Nicolin Chen To: Jason Gunthorpe CC: , , , , , , , , , Subject: Re: [PATCH v9 07/12] iommu/arm-smmu-v3-kexec: Add ASID/VMID reservation helpers Message-ID: References: <9f9d227c0adf472e93293008e7083973688d015e.1784663184.git.nicolinc@nvidia.com> <178735412602.18212.13622444378152698190.b4-review@b4> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <178735412602.18212.13622444378152698190.b4-review@b4> X-NV-OnPremToCloud: ExternallySecured X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BL6PEPF00020E60:EE_|DM4PR12MB8569:EE_ X-MS-Office365-Filtering-Correlation-Id: 3f989634-c4f4-4934-4146-08df007e7b32 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|23010399003|82310400026|1800799024|36860700016|376014|10067099003|56012099006|22082099003|18002099003|4143699003|11063799006; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: SKBVxS9k4KEwCT9evlvtOYVUGfiwdLQLN0Td4ZUB+8MaW+zQ2TD5pWsTjLQSoBXihKOI40Gn6hBK4b36D7K3dihxkDIgK39koiIRr3Tnlm14m98Agw2flPfkWL5NovIcX3EGoOxBC83mC6kCRJSwF7wocq8BeiZsiTLG75uvILdNLwxjvCZhYyMbgc/i5uh0H+3WWV8AUXCe0yXU03NRbdpoxyHYk4/PAhIQZralsxLqU2oN5www2vboXmWcdc47ThzNLIcRtehRWLYzzx+JQzf2TJAXkZRZvHIyQ0NSaRHSM8kXJEqW4KuxInlXv/Rnmm/0Lpc3W9xIV4uqAa2JL6CBV6DK5hFvUafanvXDXKA1Bv9eDxedHHaiWPkAfvmww9325gZx3EXXiuizNRELaHTLp+tx6HwPXy90tO4v9FwC06fhxxDpc53oQte4MLDS X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Aug 2026 18:52:14.0776 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 3f989634-c4f4-4934-4146-08df007e7b32 X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: BL6PEPF00020E60.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB8569 On Fri, Aug 21, 2026 at 08:15:26PM -0300, Jason Gunthorpe wrote: > > +/** > > + * arm_smmu_kexec_unresv_ids() - Roll back a failing reservation scan > > + * @smmu: SMMU device of this kernel that failed its reservation scan > > And wouldn't need this either. > > Actually I think this is overkill regardless, just leave the xarray with ASIDs > reserved. Who cares? ASID might be 8-bit that would have limited ASID slots. And it's a quite small step, so I think it might be worth keeping it. Thanks Nicolin