Merge tag 'pm+acpi-3.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from Rafael Wysocki:

 - Revert of a recent cpuidle change that caused Nehalem machines to
   hang on boot from Alex Shi.

 - USB power management fix addressing a crash in the port device
   object's release routine from Rafael J Wysocki.

 - Device PM QoS fix for a potential deadlock related to sysfs interface
   from Rafael J Wysocki.

 - Fix for a cpufreq crash when the /cpus Device Tree node is missing
   from Paolo Pisati.

 - Fix for a build issue on ia64 related to the Boot Graphics Resource
   Table (BGRT) from Tony Luck.

 - Two fixes for ACPI handles being set incorrectly for device objects
   that don't correspond to any ACPI namespace nodes in the I2C and SPI
   subsystems from Rafael J Wysocki.

 - Fix for compiler warnings related to CONFIG_PM_DEVFREQ being unset
   from Rajagopal Venkat.

 - Fix for a symbol definition typo in cpufreq_governor.h from Borislav
   Petkov.

* tag 'pm+acpi-3.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / BGRT: Don't let users configure BGRT on non X86 systems
  cpuidle / ACPI: recover percpu ACPI processor cstate
  ACPI / I2C: Use parent's ACPI_HANDLE() in acpi_i2c_register_devices()
  cpufreq: Correct header guards typo
  ACPI / SPI: Use parent's ACPI_HANDLE() in acpi_register_spi_devices()
  cpufreq: check OF node /cpus presence before dereferencing it
  PM / devfreq: Fix compiler warnings for CONFIG_PM_DEVFREQ unset
  PM / QoS: Avoid possible deadlock related to sysfs access
  USB / PM: Don't try to hide PM QoS flags from usb_port_device_release()

1 files changed, 8 insertions, 2 deletions

diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c
index 4e5b7fb8927c..37d23a0f8c56 100644
--- a/drivers/cpufreq/cpufreq-cpu0.c
+++ b/drivers/cpufreq/cpufreq-cpu0.c
@@ -178,10 +178,16 @@ static struct cpufreq_driver cpu0_cpufreq_driver = {
 
 static int cpu0_cpufreq_probe(struct platform_device *pdev)
 {
-	struct device_node *np;
+	struct device_node *np, *parent;
 	int ret;
 
-	for_each_child_of_node(of_find_node_by_path("/cpus"), np) {
+	parent = of_find_node_by_path("/cpus");
+	if (!parent) {
+		pr_err("failed to find OF /cpus\n");
+		return -ENOENT;
+	}
+
+	for_each_child_of_node(parent, np) {
 		if (of_get_property(np, "operating-points", NULL))
 			break;
 	}