From: Guenter Roeck <linux@xxxxxxxxxxxx> commit 12ead77432f2ce32dea797742316d15c5800cb32 upstream. The following traceback is seen if a critical clock fails to prepare. bcm2835-clk 3f101000.cprman: plld: couldn't lock PLL ------------[ cut here ]------------ Enabling unprepared plld_per WARNING: CPU: 1 PID: 1 at drivers/clk/clk.c:1014 clk_core_enable+0xcc/0x2c0 ... Call trace: clk_core_enable+0xcc/0x2c0 __clk_register+0x5c4/0x788 devm_clk_hw_register+0x4c/0xb0 bcm2835_register_pll_divider+0xc0/0x150 bcm2835_clk_probe+0x134/0x1e8 platform_drv_probe+0x50/0xa0 really_probe+0xd4/0x308 driver_probe_device+0x54/0xe8 device_driver_attach+0x6c/0x78 __driver_attach+0x54/0xd8 ... Check return values from clk_core_prepare() and clk_core_enable() and bail out if any of those functions returns an error. Cc: Jerome Brunet <jbrunet@xxxxxxxxxxxx> Fixes: 99652a469df1 ("clk: migrate the count of orphaned clocks at init") Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> Link: https://lkml.kernel.org/r/20191225163429.29694-1-linux@xxxxxxxxxxxx Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/clk/clk.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -3066,11 +3066,17 @@ static int __clk_core_init(struct clk_co if (core->flags & CLK_IS_CRITICAL) { unsigned long flags; - clk_core_prepare(core); + ret = clk_core_prepare(core); + if (ret) + goto out; flags = clk_enable_lock(); - clk_core_enable(core); + ret = clk_core_enable(core); clk_enable_unlock(flags); + if (ret) { + clk_core_unprepare(core); + goto out; + } } /*