From 430c502c80e542e77bcf97db13ec0e8cdf9addb0 Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Mon, 6 Jul 2026 15:43:22 -0700 Subject: [PATCH] cxl/pci: Honor -EPROBE_DEFER from component register setup cxl_pci_setup_regs() for CXL_REGLOC_RBI_COMPONENT can return -EPROBE_DEFER on a Restricted CXL Host (RCD) when the upstream port has not yet been enumerated and the Component Registers must be extracted from the RCRB. cxl_pci_probe() treats every non-zero return from that call as the benign "component registers not found" case, logs a warning, and continues. The rc is then immediately overwritten by the subsequent cxl_pci_type3_init_mailbox() call, so the deferral is silently swallowed. Return -EPROBE_DEFER instead of continuing so the probe is retried once the upstream port is available. Fixes: 733b57f262b0 ("cxl/pci: Early setup RCH dport component registers from RCRB") Reported-by: sashiko-bot@kernel.org Closes: https://lore.kernel.org/linux-cxl/ajzhsubot_PSYtHQ@MWDK4CY14F/T/#m063bbf76b1c9c293ade52ab311018ae6bba11a44 Assisted-by: Claude:claude-opus-4-8 Reviewed-by: Alison Schofield Link: https://lore.kernel.org/linux-cxl/ajzhsubot_PSYtHQ@MWDK4CY14F/T/#m063bbf76b1c9c293ade52ab311018ae6bba11a44 Link: https://patch.msgid.link/20260706224322.714934-1-dave.jiang@intel.com Signed-off-by: Dave Jiang --- drivers/cxl/pci.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index 0c9d7f8ec9e4..9d9952e391ac 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -823,10 +823,13 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) */ rc = cxl_pci_setup_regs(pdev, CXL_REGLOC_RBI_COMPONENT, &cxlds->reg_map); - if (rc) + if (rc) { + if (rc == -EPROBE_DEFER) + return rc; dev_warn(&pdev->dev, "No component registers (%d)\n", rc); - else if (!cxlds->reg_map.component_map.ras.valid) + } else if (!cxlds->reg_map.component_map.ras.valid) { dev_dbg(&pdev->dev, "RAS registers not found\n"); + } rc = cxl_pci_type3_init_mailbox(cxlds); if (rc)