On 10/19/2013 12:49 AM, Thierry Reding wrote:
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@xxxxxxxxxx> --- drivers/clocksource/clksrc-of.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/clocksource/clksrc-of.c b/drivers/clocksource/clksrc-of.c index 35639cf4..b9ddd9e 100644 --- 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); } }
Applied to my tree for 3.13 fixes. -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
