cpufreq: fix null object access on Transmeta CPU

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@gmail.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Chuck Ebbert <cebbert@redhat.com>
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
CHIKAMA masaki 2008-06-05 22:46:33 -07:00 committed by Linus Torvalds
parent 10732c35df
commit 879000f944

View File

@ -625,7 +625,7 @@ static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy,
unsigned int freq = 0; unsigned int freq = 0;
unsigned int ret; unsigned int ret;
if (!policy->governor->store_setspeed) if (!policy->governor || !policy->governor->store_setspeed)
return -EINVAL; return -EINVAL;
ret = sscanf(buf, "%u", &freq); ret = sscanf(buf, "%u", &freq);
@ -639,7 +639,7 @@ static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy,
static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) 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 sprintf(buf, "<unsupported>\n");
return policy->governor->show_setspeed(policy, buf); return policy->governor->show_setspeed(policy, buf);