powerpc/pmac: replace current->state by set_current_state()

Use helper functions to access current->state.
Direct assignments are prone to races and therefore buggy.

current->state = TASK_RUNNING can be replaced by __set_current_state()

Thanks to Peter Zijlstra for the exact definition of the problem.

Suggested-By: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/macintosh/via-pmu.c b/drivers/macintosh/via-pmu.c
index aed3cb07a6fa..f9512bfa6c3c 100644
--- a/drivers/macintosh/via-pmu.c
+++ b/drivers/macintosh/via-pmu.c
@@ -2112,7 +2112,7 @@ pmu_read(struct file *file, char __user *buf,
 
         spin_lock_irqsave(&pp->lock, flags);
         add_wait_queue(&pp->wait, &wait);
-        current->state = TASK_INTERRUPTIBLE;
+        set_current_state(TASK_INTERRUPTIBLE);
 
         for (;;) {
                 ret = -EAGAIN;
@@ -2141,7 +2141,7 @@ pmu_read(struct file *file, char __user *buf,
                 schedule();
                 spin_lock_irqsave(&pp->lock, flags);
         }
-        current->state = TASK_RUNNING;
+        __set_current_state(TASK_RUNNING);
         remove_wait_queue(&pp->wait, &wait);
         spin_unlock_irqrestore(&pp->lock, flags);