[patch 50/50] cpufreq: fix null object access on Transmeta CPU

[Chris Wright]

-stable review patch.  If anyone has any objections, please let us know.
---------------------

From: CHIKAMA masaki <masaki.chikama@xxxxxxxxx>

upstream commit: 879000f94442860e72c934f9e568989bc7fb8ec4

If cpu specific cpufreq driver(i.e.  longrun) has "setpolicy" function,
governor object isn't set into cpufreq_policy object at "__cpufreq_set_policy"
function in driver/cpufreq/cpufreq.c .

This causes a null object access at "store_scaling_setspeed" and
"show_scaling_setspeed" function in driver/cpufreq/cpufreq.c when reading or
writing through /sys interface (ex.  cat
/sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed)

Addresses:
	http://bugzilla.kernel.org/show_bug.cgi?id=10654
	https://bugzilla.redhat.com/show_bug.cgi?id=443354

Signed-off-by: CHIKAMA Masaki <masaki.chikama@xxxxxxxxx>
Cc: Dave Jones <davej@xxxxxxxxxxxxxxxxx>
Cc: Chuck Ebbert <cebbert@xxxxxxxxxx>
Acked-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Chris Wright <chrisw@xxxxxxxxxxxx>
---
 drivers/cpufreq/cpufreq.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -607,7 +607,7 @@ static ssize_t store_scaling_setspeed(st
 	unsigned int freq = 0;
 	unsigned int ret;
 
-	if (!policy->governor->store_setspeed)
+	if (!policy->governor || !policy->governor->store_setspeed)
 		return -EINVAL;
 
 	ret = sscanf(buf, "%u", &freq);
@@ -621,7 +621,7 @@ static ssize_t store_scaling_setspeed(st
 
 static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf)
 {
-	if (!policy->governor->show_setspeed)
+	if (!policy->governor || !policy->governor->show_setspeed)
 		return sprintf(buf, "<unsupported>\n");
 
 	return policy->governor->show_setspeed(policy, buf);

-- 
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