From a1eff92bc890b4c8697527bb05bd72f2428c3ce7 Mon Sep 17 00:00:00 2001 From: John Baldwin Date: Tue, 6 Dec 2016 00:36:02 +0000 Subject: [PATCH] Don't attach to Host-PCI bridges with a bad bus number. If the bus number assigned to a Host-PCI bridge doesn't match the first bus number in the associated producer range from _CRS, print a warning and fail to attach rather than panicking due to an assertion failure. At least one single-socket Dell machine leaves a "ghost" Host-PCI bridge device in the ACPI namespace that seems to correspond to the I/O hub in the second socket of a two-socket machine. However, the BIOS doesn't configure the settings for this "ghost" bridge correctly, nor does it have any PCI devices behind it. Tested by: royger MFC after: 2 weeks --- sys/dev/acpica/acpi_pcib_acpi.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/sys/dev/acpica/acpi_pcib_acpi.c b/sys/dev/acpica/acpi_pcib_acpi.c index dfd95bc2538..190674a7462 100644 --- a/sys/dev/acpica/acpi_pcib_acpi.c +++ b/sys/dev/acpica/acpi_pcib_acpi.c @@ -488,10 +488,17 @@ acpi_pcib_acpi_attach(device_t dev) pci_domain_release_bus(sc->ap_segment, dev, rid, bus_res); } } else { -#ifdef INVARIANTS - if (first_decoded_bus(sc, &start) == 0) - KASSERT(start == sc->ap_bus, ("bus number mismatch")); -#endif + /* + * Require the bus number from _BBN to match the start of any + * decoded range. + */ + if (first_decoded_bus(sc, &start) == 0 && sc->ap_bus != start) { + device_printf(dev, + "bus number %d does not match start of decoded range %ju\n", + sc->ap_bus, (uintmax_t)start); + pcib_host_res_free(dev, &sc->ap_host_res); + return (ENXIO); + } } #else /* @@ -514,6 +521,9 @@ acpi_pcib_acpi_attach(device_t dev) if (device_add_child(dev, "pci", -1) == NULL) { device_printf(device_get_parent(dev), "couldn't attach pci bus\n"); +#if defined(NEW_PCIB) && defined(PCI_RES_BUS) + pcib_host_res_free(dev, &sc->ap_host_res); +#endif return (ENXIO); } return (bus_generic_attach(dev));