From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Tue, 20 Aug 2013 22:52:21 +0100 Subject: [PATCH v2 4/4] clkdev: Fix race condition in clock lookup from device tree In-Reply-To: <1377020063-30213-5-git-send-email-s.nawrocki@samsung.com> References: <1377020063-30213-1-git-send-email-s.nawrocki@samsung.com> <1377020063-30213-5-git-send-email-s.nawrocki@samsung.com> Message-ID: <20130820215221.GH17845@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Aug 20, 2013 at 07:34:23PM +0200, Sylwester Nawrocki wrote: > There is currently a race condition in the device tree part of clk_get() > function, since the pointer returned from of_clk_get_by_name() may become > invalid before __clk_get() call. I.e. due to the clock provider driver > remove() callback being called in between of_clk_get_by_name() and > __clk_get(). > > Fix this by doing both the look up and __clk_get() operations with the > clock providers list mutex held. This ensures that the clock pointer > returned from __of_clk_get_from_provider() call and passed to __clk_get() > is valid, as long as the clock supplier module first removes its clock > provider instance and then does clk_unregister() on the corresponding > clocks. > > Signed-off-by: Sylwester Nawrocki > Signed-off-by: Kyungmin Park > Reviewed-by: Mike Turquette Thanks. Acked-by: Russell King