Commit 89f7e9de authored Dec 12, 2014 by Stephen Boyd Committed by Michael Turquette Dec 15, 2014

clk: Really fix deadlock with mmap_sem



Commit 6314b679 (clk: Don't hold prepare_lock across debugfs
creation, 2014-09-04) forgot to update one place where we hold
the prepare_lock while creating debugfs directories. This means
we still have the chance of a deadlock that the commit was trying
to fix. Actually fix it by moving the debugfs creation outside
the prepare_lock.

Cc: <stable@vger.kernel.org> # 3.18
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fixes: 6314b679 "clk: Don't hold prepare_lock across debugfs creation"
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
[mturquette@linaro.org: removed lockdep_assert]

parent c9b92814

drivers/clk/clk.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -240,7 +240,6 @@ static const struct file_operations clk_dump_fops = {
		.release = single_release,
		};

		/* caller must hold prepare_lock */
		static int clk_debug_create_one(struct clk clk, struct dentry pdentry)
		{
		struct dentry *d;
		@@ -1944,7 +1943,6 @@ int __clk_init(struct device dev, struct clk clk)
		else
		clk->rate = 0;

		clk_debug_register(clk);
		/*
		* walk the list of orphan clocks and reparent any that are children of
		* this clock
		@@ -1979,6 +1977,9 @@ int __clk_init(struct device dev, struct clk clk)
		out:
		clk_prepare_unlock();

		if (!ret)
		clk_debug_register(clk);

		return ret;
		}