Commit bd0fa9bb455d introduced a failure path to cpufreq_update_policy() if
cpufreq_driver->get(cpu) returns NULL. However, it jumps to the 'no_policy'
label, which exits without unlocking any of the locks the function acquired
earlier. This causes later calls into cpufreq to hang.
Fix this by creating a new 'unlock' label and jumping to that instead.
v2: Delete the no_policy label and just return early if policy is NULL.
Fixes: bd0fa9bb455d ("cpufreq: Return error if ->get() failed in
cpufreq_update_policy()")
Link:
https://devtalk.nvidia.com/default/topic/751903/kernel-3-15-and-nv-drivers-337-340-failed-to-initialize-the-nvidia-kernel-module-gtx-550-ti-/
Cc: Viresh Kumar <viresh.ku...@linaro.org>
Cc: Rafael J. Wysocki <rafael.j.wyso...@intel.com>
Signed-off-by: Aaron Plattner <aplatt...@nvidia.com>
---
v1 of this was tested by the user affected by the problem, but I don't have his
email address so I can't add it as a Tested-by line.
drivers/cpufreq/cpufreq.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index aed2b0cb83dc..62259d27f03e 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -2242,10 +2242,8 @@ int cpufreq_update_policy(unsigned int cpu)
struct cpufreq_policy new_policy;
int ret;
- if (!policy) {
- ret = -ENODEV;
- goto no_policy;
- }
+ if (!policy)
+ return -ENODEV;
down_write(&policy->rwsem);
@@ -2264,7 +2262,7 @@ int cpufreq_update_policy(unsigned int cpu)
new_policy.cur = cpufreq_driver->get(cpu);
if (WARN_ON(!new_policy.cur)) {
ret = -EIO;
- goto no_policy;
+ goto unlock;
}
if (!policy->cur) {
@@ -2279,10 +2277,10 @@ int cpufreq_update_policy(unsigned int cpu)
ret = cpufreq_set_policy(policy, &new_policy);
+unlock:
up_write(&policy->rwsem);
cpufreq_cpu_put(policy);
-no_policy:
return ret;
}
EXPORT_SYMBOL(cpufreq_update_policy);
--
2.0.0
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