From d0cdef6e87ebc1241d7e407d5e1b14e6bb836ae9 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Wed, 25 Sep 2013 23:26:24 +0100 Subject: ARM: 7842/1: MCPM: don't explode if invoked without being initialized first Currently mcpm_cpu_power_down() and mcpm_cpu_suspend() trigger BUG() if mcpm_platform_register() is not called beforehand. This may occur for many reasons such as some incomplete device tree passed to the kernel or the like. Let's be nicer to users and avoid killing the kernel if that happens by logging a warning and returning to the caller. The mcpm_cpu_suspend() user is already set to deal with this situation, and so is cpu_die() invoking mcpm_cpu_die(). The problematic case would have been the B.L switcher's usage of mcpm_cpu_power_down(), however it has to call mcpm_cpu_power_up() first which is already set to catch an error resulting from a missing mcpm_platform_register() call. Signed-off-by: Nicolas Pitre Signed-off-by: Russell King --- arch/arm/common/mcpm_entry.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'arch/arm/common/mcpm_entry.c') diff --git a/arch/arm/common/mcpm_entry.c b/arch/arm/common/mcpm_entry.c index 370236dd1a0..990250965f2 100644 --- a/arch/arm/common/mcpm_entry.c +++ b/arch/arm/common/mcpm_entry.c @@ -51,7 +51,8 @@ void mcpm_cpu_power_down(void) { phys_reset_t phys_reset; - BUG_ON(!platform_ops); + if (WARN_ON_ONCE(!platform_ops || !platform_ops->power_down)) + return; BUG_ON(!irqs_disabled()); /* @@ -93,7 +94,8 @@ void mcpm_cpu_suspend(u64 expected_residency) { phys_reset_t phys_reset; - BUG_ON(!platform_ops); + if (WARN_ON_ONCE(!platform_ops || !platform_ops->suspend)) + return; BUG_ON(!irqs_disabled()); /* Very similar to mcpm_cpu_power_down() */ -- cgit v1.2.3