From 508d392ae0bb3729d4c18628e021968a1b11b32c Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Tue, 2 Jun 2020 16:42:33 -0500 Subject: [PATCH] PCI/ACPI: Clarify message about _OSC failure This message: acpi PNP0A08:02: _OSC failed (AE_NOT_FOUND); disabling ASPM is alarming and slightly misleading. Per the PCI Firmware Spec, r3.2, sec 4.5.1, _OSC is required for PCIe hierarchies. If _OSC is absent or fails, the OS must not attempt to use any of the features defined for _OSC. That includes native hotplug, native PME, AER, and other things as well as ASPM. Rephrase the message to: acpi PNP0A08:02: _OSC: platform retains control of PCIe features (AE_NOT_FOUND) Previous discussion at https://lore.kernel.org/r/20200602223618.GA845676@bjorn-Precision-5520/ Signed-off-by: Bjorn Helgaas Reviewed-by: Sinan Kaya Acked-by: Rafael J. Wysocki Cc: Yicong Yang --- drivers/acpi/pci_root.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index ea08b3298e73..dcd593766a64 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -441,9 +441,8 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm, if ((status == AE_NOT_FOUND) && !is_pcie) return; - dev_info(&device->dev, "_OSC failed (%s)%s\n", - acpi_format_exception(status), - pcie_aspm_support_enabled() ? "; disabling ASPM" : ""); + dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n", + acpi_format_exception(status)); return; } @@ -499,7 +498,7 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm, } else { decode_osc_control(root, "OS requested", requested); decode_osc_control(root, "platform willing to grant", control); - dev_info(&device->dev, "_OSC failed (%s); disabling ASPM\n", + dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n", acpi_format_exception(status)); /* -- 2.11.0