pci_create_root_bus is called with NULL as parent in ACPI. This ends up calling pci_bus_assign_domain_nr with a NULL parent, which crashes when dereferencing parent. Fix this by providing a way to set the ACPI domain number and ACPI companion in PCI code. We define pci_acpi_set_companion() to set the ACPI companion pointer and acpi_pci_get_segment() and to get the PCI domain number. These functions are stubs for now, the implementation will be done when the ACPI generic PCI controller is added. pci_bus_assign_domain_nr is updated to call acpi_pci_get_segment() to get the domain number to set on the root bus, in case of ACPI. Signed-off-by: Jayachandran C <jchandra@xxxxxxxxxxxx> --- drivers/pci/pci.c | 15 ++++++++++++++- drivers/pci/probe.c | 2 ++ include/linux/pci-acpi.h | 11 ++++++++++- 3 files changed, 26 insertions(+), 2 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 602eb42..5a3222d 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -20,6 +20,7 @@ #include <linux/string.h> #include <linux/log2.h> #include <linux/pci-aspm.h> +#include <linux/pci-acpi.h> #include <linux/pm_wakeup.h> #include <linux/interrupt.h> #include <linux/device.h> @@ -4772,9 +4773,21 @@ int pci_get_new_domain_nr(void) void pci_bus_assign_domain_nr(struct pci_bus *bus, struct device *parent) { static int use_dt_domains = -1; - int domain = of_get_pci_domain_nr(parent->of_node); + int domain; /* + * Handle ACPI early + * + * The companion is not set at this point, and ACPI sets parent to + * NULL, we have to try to get the segment from acpi root info. + */ + if (!parent || !parent->of_node) { + bus->domain_nr = acpi_pci_get_segment(bus->sysdata); + return; + } + + domain = of_get_pci_domain_nr(parent->of_node); + /* * Check DT domain and use_dt_domains values. * * If DT domain property is valid (domain >= 0) and diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 6d7ab9b..f1faede 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -13,6 +13,7 @@ #include <linux/module.h> #include <linux/cpumask.h> #include <linux/pci-aspm.h> +#include <linux/pci-acpi.h> #include <linux/aer.h> #include <linux/acpi.h> #include <asm-generic/pci-bridge.h> @@ -2100,6 +2101,7 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, bridge->dev.parent = parent; bridge->dev.release = pci_release_host_bridge_dev; dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus); + pci_acpi_set_companion(bridge); error = pcibios_root_bridge_prepare(bridge); if (error) { kfree(bridge); diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h index e9450ef..d410885 100644 --- a/include/linux/pci-acpi.h +++ b/include/linux/pci-acpi.h @@ -138,12 +138,21 @@ extern struct list_head pci_mmcfg_list; #define PCI_MMCFG_BUS_OFFSET(bus) ((bus) << 20) #define PCI_MMCFG_OFFSET(bus, devfn) ((bus) << 20 | (devfn) << 12) - #else /* CONFIG_ACPI */ static inline void acpi_pci_add_bus(struct pci_bus *bus) { } static inline void acpi_pci_remove_bus(struct pci_bus *bus) { } #endif /* CONFIG_ACPI */ +static inline void pci_acpi_set_companion(struct pci_host_bridge *bridge) +{ + /* leave it to the platform for now */ +} + +static inline u16 acpi_pci_get_segment(void *sysdata) +{ + return 0; +} + #ifdef CONFIG_ACPI_APEI extern bool aer_acpi_firmware_first(void); #else -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html