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Wed, 20 May 2026 13:20:57 -0700 Date: Wed, 20 May 2026 13:20:56 -0700 From: Nicolin Chen To: Bjorn Helgaas CC: , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v5 1/3] PCI: Add pci_ats_required() for CXL.cache capable devices Message-ID: References: <9e01e6d39deff2bf751da3e1abb43f35a9169194.1779304390.git.nicolinc@nvidia.com> <20260520200327.GA88349@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20260520200327.GA88349@bhelgaas> X-NV-OnPremToCloud: ExternallySecured X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS3PEPF000099E2:EE_|BN7PPF7F4CD71A4:EE_ X-MS-Office365-Filtering-Correlation-Id: 38e7a6f2-4b0a-4b31-6f71-08deb6ad5b62 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|82310400026|36860700016|376014|7416014|4143699003|56012099003|22082099003|18002099003|11063799006; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:216.228.117.160;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:dc6edge1.nvidia.com;CAT:NONE;SFS:(13230040)(1800799024)(82310400026)(36860700016)(376014)(7416014)(4143699003)(56012099003)(22082099003)(18002099003)(11063799006);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: sy/Am6Rc2e0ig+G37KAzR4v8CiN8SCT59b/zu+CmXroCcFUg9Su0Y8Pr+S0XqLGzPIp84pMdo08H0eVMGlYtD8xFVRLkmJG9cbValxeriW9Tc1hynf7qbrfs/vFwJSBmGIWfNcfl5fltD/GZ4sP0mlsnmVxFpvLiz/TlkeJ6B2RZmk6sRrdyp3w6aqgdmT+NGjZxViYYOxQ0hnQA/9qi4ZLBXJP0q6U/84+gMyz66s6PKfOstoauIx65gNpN2Kxxx4bHfRqbHlUDU44MJIz95p8S2x6OGQdP+yXz9gWu8tKVjPtd92ZdYoZN5D5FHvqpVShYaopnenZ4vEtVpG8bfhg+UpemVFsvkK8ffhTmBB7r2MA3T7r64cpoJh+cXB0O7AQ0CS6LlLlWs9ZsNHFo4+X2Q/CHter5GRMhq6XYxODmGfXGSUXydpApIlJR8BCQ X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 May 2026 20:21:21.0462 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 38e7a6f2-4b0a-4b31-6f71-08deb6ad5b62 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: DS3PEPF000099E2.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN7PPF7F4CD71A4 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260520_132133_085842_0087E7E4 X-CRM114-Status: GOOD ( 11.04 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, May 20, 2026 at 03:03:27PM -0500, Bjorn Helgaas wrote: > On Wed, May 20, 2026 at 12:46:08PM -0700, Nicolin Chen wrote: > > +bool pci_ats_required(struct pci_dev *pdev) > > +{ > > + if (pci_ats_disabled() || !pci_ats_supported(pdev)) > > + return false; > > I still have the question about whether it's necessary to test > pci_ats_disabled() here. I think pci_ats_supported() should return > false if pci_ats_disabled() returns true. Sorry, it fell through the crack. And you are right that. pci_ats_disabled() seems redundant. I can respin a v6. Thanks Nicolin