clocksource: clksrc-of: Do not drop unheld reference on device node

When booting a recent kernel on ARM with OF_DYNAMIC enabled, the kernel
warns about the following:

	[    0.000000] ERROR: Bad of_node_put() on /timer@50004600
	[    0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.12.0-rc5-next-20131017-00077-gedfd827-dirty #406
	[    0.000000] [<c0015b68>] (unwind_backtrace+0x0/0xf4) from [<c00117e4>] (show_stack+0x10/0x14)
	[    0.000000] [<c00117e4>] (show_stack+0x10/0x14) from [<c055f734>] (dump_stack+0x9c/0xc8)
	[    0.000000] [<c055f734>] (dump_stack+0x9c/0xc8) from [<c03b47d4>] (of_node_release+0x90/0x9c)
	[    0.000000] [<c03b47d4>] (of_node_release+0x90/0x9c) from [<c03b5084>] (of_find_matching_node_and_match+0x78/0xb4)
	[    0.000000] [<c03b5084>] (of_find_matching_node_and_match+0x78/0xb4) from [<c07887c8>] (clocksource_of_init+0x60/0x70)
	[    0.000000] [<c07887c8>] (clocksource_of_init+0x60/0x70) from [<c076e99c>] (start_kernel+0x1f4/0x33c)
	[    0.000000] [<c076e99c>] (start_kernel+0x1f4/0x33c) from [<80008074>] (0x80008074)

This is caused by clocksource_of_init() dropping a reference on the
device node that it never took. The reference taken by the loop is
implicitly dropped on subsequent iterations. See the implementation of
and the comment on top of the of_find_matching_node_and_match()
function for reference (no pun intended).

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

diff --git a/drivers/clocksource/clksrc-of.c b/drivers/clocksource/clksrc-of.c
index 35639cf4e5a208af89c9b692eae32227bcefc5d3..b9ddd9e3a2f599e2cc7424c1eac18d4280b2f850 100644 (file)
--- a/drivers/clocksource/clksrc-of.c
+++ b/drivers/clocksource/clksrc-of.c
@@ -35,6 +35,5 @@ void __init clocksource_of_init(void)
 
                init_func = match->data;
                init_func(np);
-               of_node_put(np);
        }
 }