Re: [PATCH v13 3/6] clk: Make clk API return per-user struct clk instances

From: Sylwester Nawrocki
Date: Thu Feb 05 2015 - 15:06:59 EST


On 05/02/15 20:44, Sylwester Nawrocki wrote:
>> +void __clk_put(struct clk *clk)
>> > +{
>> > + if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
>> > + return;
>> > +
>> > + clk_core_put(clk->core);
>> > + kfree(clk);
>
> Why do we have kfree() here? clk_get() doesn't allocate the data structure
> being freed here. What happens if we do clk_get(), clk_put(), clk_get()
> on same clock?
>
> I suspect __clk_free_clk() should be called in __clk_release() callback
> instead, but then there is an issue of safely getting reference to
> struct clk from struct clk_core pointer.

Please ignore this comment, I missed __clk_create_clk() calls in clkdev.c
Anyway, in current -next I'm seeing random pointer dereferences while
booting Odroid U3, I'll get back to debugging this tomorrow morning.

--
Regards,
Sylwester
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