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 away to set the ACPI domain number, we define
acpi_pci_sysdata_to_root_info() to get the acpi root info from
sysdata. This is a simple cast the generic ACPI PCI implementation.
Similarly, setting up the ACPI companion in case of generic ACPI PCI
implementation is staright forward.
Signed-off-by: Jayachandran C <jchandra@xxxxxxxxxxxx>
---
drivers/pci/pci.c | 19 ++++++++++++++++++-
drivers/pci/probe.c | 2 ++
include/linux/pci-acpi.h | 28 +++++++++++++++++++++++++++-
3 files changed, 47 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 314db8c..f578af4 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 +4773,25 @@ 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) {
+ struct acpi_pci_root_info *ci;
+
+ ci = acpi_pci_sysdata_to_root_info(bus->sysdata);
+ if (ci)
+ bus->domain_nr = ci->root->segment;
+ 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 edb1984..5af66496 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>
@@ -2105,6 +2106,7 @@ 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..79448ce 100644
--- a/include/linux/pci-acpi.h
+++ b/include/linux/pci-acpi.h
@@ -138,12 +138,38 @@ 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 */
+#if defined(CONFIG_ACPI) && defined(CONFIG_ACPI_PCI_HOST_GENERIC)
+static inline struct acpi_pci_root_info *acpi_pci_sysdata_to_root_info(void *sd)
+{
+ return (struct acpi_pci_root_info *)sd;
+}
+
+static inline void pci_acpi_set_companion(struct pci_host_bridge *bridge)
+{
+ struct pci_bus *b = bridge->bus;
+ struct acpi_pci_root_info *ci;
+
+ ci = acpi_pci_sysdata_to_root_info(b->sysdata);
+ if (ci)
+ ACPI_COMPANION_SET(&bridge->dev, ci->bridge);
+}
+#else
+static inline struct acpi_pci_root_info *acpi_pci_sysdata_to_root_info(void *sd)
+{
+ return NULL;
+}
+
+static inline void pci_acpi_set_companion(struct pci_host_bridge *bridge)
+{
+ /* leave it to the platform for now */
+}
+#endif
+
#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-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
