On Sat, Sep 21, 2013 at 12:00:06PM +0200, Jean-Francois Moine wrote:
diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index 442a313..f8b28d9 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -157,8 +157,13 @@ struct clk *clk_get(struct device *dev, const char *con_id)
if (dev) { clk = of_clk_get_by_name(dev->of_node, con_id);
if (!IS_ERR(clk) && __clk_get(clk))return clk;
if (!IS_ERR(clk)) {if (__clk_get(clk))return clk;} else {if (PTR_ERR(clk) == -EPROBE_DEFER)return clk;}
Thanks for patching this file and bringing this code to my attention. The original is fscked. Calling __clk_get() outside of any lock is a serious bug and leads to races.
Also, a failing __clk_get() probably should not drop through to clk_get_sys(), but should instead do this:
if (!IS_ERR(clk)) { if (!__clk_get(clk)) clk = ERR_PTR(-ENOENT); return clk; }
since a _found_ clock but one which can't be used (due to the module going away) is not a reason to drop through to clk_get_sys().
Which means your change should look like this:
if (!IS_ERR(clk)) { if (!__clk_get(clk)) clk = ERR_PTR(-ENOENT); return clk; } if (PTR_ERR(clk) == -EPROBE_DEFER) return clk;