clk: Don't try to use a struct clk* after it could have been freed

As __clk_release could call kfree on clk and then we wouldn't have a safe way
of getting the module that owns the clock.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Fixes: fcb0ee6a3d33 ("clk: Implement clk_unregister")
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 42f940ff5edf..609e9db1a69a 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2268,14 +2268,17 @@ int __clk_get(struct clk *clk)
 
 void __clk_put(struct clk *clk)
 {
+        struct module *owner;
+
         if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
                 return;
 
         clk_prepare_lock();
+        owner = clk->owner;
         kref_put(&clk->ref, __clk_release);
         clk_prepare_unlock();
 
-        module_put(clk->owner);
+        module_put(owner);
 }
 
 /***        clk rate change notifiers        ***/