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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?3ldiZwxiIIIXgKGvoeUgQW45xOc9IpuI+d0DXkANxi7qIndTQZaKjrfJXNlL?= =?us-ascii?Q?K9vIbIfnBCbwT76OBq4P01QwvgdLaNMlvlfcCOCF9452no9ssMq632Ih+RoJ?= =?us-ascii?Q?PNpAEja6OXN13TidBXVdpTvd3CXxzGBGHE3J6+PK5lmSE3ilAH986CQamlJL?= =?us-ascii?Q?EdlFTyy1W5QJ/6slcNdpsry66edrKFU4xzUm3Yw1I+6KEbs8QgDKyUpjAalc?= =?us-ascii?Q?ydQ9R/4Mw6GHhdsRPYsN6t01oNzezGdBTkTJ63K+ZEDWyvJBg9vZHXVwmw+Y?= =?us-ascii?Q?fd7pT8uk+hqIvYpQNitg+Jg/C+KiE/1UIXNGXNaW913ftzm0eh3ggiNir1xl?= =?us-ascii?Q?csLjDt/wcmwcNC6NLELtGWIUxdZICpWxglG3agYGfv2w65IPbGKH73SCdG4j?= =?us-ascii?Q?e16UwXC5y7sUgdz8mcde2p7HIVPcCS8z8SUKzvmAbDYFYVKLuQQprLY+arA4?= =?us-ascii?Q?QQSZ9XKfoaFIxjQ6RNSNFuzfIpfVSJ1SkWcbjGRAso4GYcPuxTRxzO4GThYa?= =?us-ascii?Q?zTbf/qWNcL/jKU3oWcWG8l0s/xQMVYNyeBR83yvQ/o871Tz/gf3/yEzGHXK6?= =?us-ascii?Q?gGz6IL0hvyVtMX+jagDtU0P2zri4PCTgjXLUHECcn0Y9lA4sFcflRAYmC3EW?= =?us-ascii?Q?Z/j4YN6tuOzjhSV0sRFqlNdCnOlZiBqoTR91/f+BycFAIiGwFPD6LvAO6SN9?= =?us-ascii?Q?cKmIe+IqqNCVaG5O18PGz9u0viXuri4vdi4RyDvARoKYzirWZ2lySjIEg/C7?= =?us-ascii?Q?QBDCOL4pa5YYCylYlTviaDsp+LpQ7qYJWXZZu4jZHV82YYL7H4uN2+cV8QNn?= =?us-ascii?Q?NTqLNzSoluVzyTlcoXLgF0MdXHGFQtSslW2zGsTAdlwV4C/MPmvyXRqOC9gp?= =?us-ascii?Q?47SNJ6GNcfriIWHivNK8MOA8j/TA0L7uARnDUNyW7M4fbCcRMlbT26ehp0NG?= =?us-ascii?Q?AKLkYjBahfMkj5unm1sl9N7H12QmkeXqr2ETwMO+38HkL575e+IgKB1UQCRW?= =?us-ascii?Q?NljMddMsspKIxRD7olOnZ69cOeNzRsisDl4O99oLec5CHX/1yz+V3/7TEnEM?= =?us-ascii?Q?oq9UVzt3nV/y0dHOfH01vb9hz/kYth90dnHpAfJ0RG4d/6w71PKBtRcAOzwk?= =?us-ascii?Q?1NkffV1T5OlcT1qCfRyFgIbhtBhbliRL03VeYuz9X9/qmb1FfpMNNaqPfxsR?= =?us-ascii?Q?XB3/nNgKg5LxUv/+HhXC4HSuI7Ipc/5BxxlH+eUMp2caRLbfVSyakp7ml+Nl?= =?us-ascii?Q?hVICKuChS0T4xoVBZkvSbZkZ5xiqmzZBnRhUiVGKn0EgKii8QzYQyzAaKteV?= =?us-ascii?Q?BmXoon15iHR5sFSCE1ydJeFbd2ELXtMAP7ls71ObfuNaNESnS5DbxAuBh9K2?= =?us-ascii?Q?xzEgNBwPqQA5Fgfu9OrrIf47NG6hkv1SRjTujz2SwDILSogZW3WIaZ1C1tJN?= =?us-ascii?Q?V6eRq75qL831TdwT+pkowXlx6z/uQHOSi0deM+yzV9NOs5n2c8hN7AYCJzt1?= =?us-ascii?Q?bn3HQf+xMAgLFBIPOMXEsi/5JKu2XkRoaLGD8yPjZ8D/LiVlmRk+QTmu76cc?= =?us-ascii?Q?Jxy/DlUiWMk6Pu8wpXhYICag1Ahf51JXFYq/6SgAJq5ORl/a/DX5vUrAOU3K?= =?us-ascii?Q?tXjofC2k2RFocwXPaQWScODwpSpRLvSe9olDtPc5EVBr+zT/7Qm0paXHt0/p?= =?us-ascii?Q?bIT29d/A28dO4vkkAOD72vVryH7F2d2Q+m2/pPYAWnlqH9vnObflHBloxjZk?= =?us-ascii?Q?Ibh3Nv/lMg=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: ea2df539-a70e-4d48-4838-08ded29144be X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB2370.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Jun 2026 08:10:50.4675 (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: dXHOkMzGTti0T5oEbQvvj1D7ae8ZipaekMhbZv2Qc3BHsWSmav162XLr98lLou6rNDxyXzYK7Y4PFvoO73JSPw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB7118 On Fri, Jun 19, 2026 at 01:03:56AM +0800, Wei Hou wrote: > The driver's design intent is that missing or malformed component > registers should not prevent mailbox initialization. cxl_pci_probe() > already reflects this: the CXL_REGLOC_RBI_COMPONENT setup path only > emits a dev_warn() and continues when component registers are absent, > rather than returning an error. > > The check 'if (!cxlds->reg_map.device_map.mbox.valid)' violates this > intent and is also technically incorrect for two reasons: > > 1. Wrong struct: the MEMDEV register block is enumerated into a local > variable 'map', not into 'cxlds->reg_map'. The device_map.mbox.valid > field inside cxlds->reg_map is never written by the MEMDEV probe and > will always read as zero regardless of actual hardware capability. > > 2. Already validated: cxl_pci_setup_regs(CXL_REGLOC_RBI_MEMDEV) calls > cxl_probe_regs() which explicitly checks mbox.valid and returns > -ENXIO if the mailbox is absent. If that check passes, the mailbox is > guaranteed to be present by the time cxl_pci_type3_init_mailbox() is > called. > > The value that the check actually reads is component_map.ras.valid, > which aliases device_map.mbox.valid in the union. This is populated by > the COMPONENT probe, not the MEMDEV probe. On devices where the > component register BAR does not implement a CXL Component Capability > Array (e.g. certain DCD devices), cxl_probe_component_regs() returns > early leaving ras.valid=false. Through the union, this makes mbox.valid > read as false, causing cxl_pci_type3_init_mailbox() to return -ENODEV > (-19) even though the mailbox hardware is fully functional. > > Remove the check. Mailbox presence has already been validated by > cxl_pci_setup_regs(CXL_REGLOC_RBI_MEMDEV). The presence or absence of > component registers is irrelevant to mailbox initialization. > > Signed-off-by: Wei Hou > --- > drivers/cxl/pci.c | 6 ------ > 1 file changed, 6 deletions(-) > > diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c > index bace662dc988..e44e5d209900 100644 > --- a/drivers/cxl/pci.c > +++ b/drivers/cxl/pci.c > @@ -691,12 +691,6 @@ static int cxl_pci_type3_init_mailbox(struct cxl_dev_state *cxlds) > { > int rc; > > - /* > - * Fail the init if there's no mailbox. For a type3 this is out of spec. > - */ > - if (!cxlds->reg_map.device_map.mbox.valid) > - return -ENODEV; > - > rc = cxl_mailbox_init(&cxlds->cxl_mbox, cxlds->dev); > if (rc) > return rc; > -- > 2.24.1 > > Btw, You missed to sent this one to many people, I'll add them this time for you --Richard