cpufreq: fix missing unlocks in cpufreq_add_dev error paths.

Ingo hit some BUG_ONs that were probably caused by these missing unlocks
causing an unbalance.  He couldn't reproduce the bug reliably, so it's
unknown that it's definitly fixing the problem he hit, but it's a fairly
good chance, and this fixes an obvious bug.

[ Dave: "Ingo followed up that he hit some lockdep related output with
         this applied, so it may not be right.  I'll look at it after
         xmas if no-one has it figured out before then."
  Akpm: "It looks pretty correct to me though." ]

Signed-off-by: Dave Jones <davej@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 5e626b12b97eb758b12a652d4fd8e5967ee76307..79581fab82d69464a77cf6c51363cec85fede91f 100644 (file)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -841,19 +841,25 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
        drv_attr = cpufreq_driver->attr;
        while ((drv_attr) && (*drv_attr)) {
                ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr));
-               if (ret)
+               if (ret) {
+                       unlock_policy_rwsem_write(cpu);
                        goto err_out_driver_exit;
+               }
                drv_attr++;
        }
        if (cpufreq_driver->get){
                ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr);
-               if (ret)
+               if (ret) {
+                       unlock_policy_rwsem_write(cpu);
                        goto err_out_driver_exit;
+               }
        }
        if (cpufreq_driver->target){
                ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr);
-               if (ret)
+               if (ret) {
+                       unlock_policy_rwsem_write(cpu);
                        goto err_out_driver_exit;
+               }
        }
 
        spin_lock_irqsave(&cpufreq_driver_lock, flags);