Executing loops such as: while (1) cpu_relax(); with interrupts disabled results in a livelock of the entire system, as other CPUs are prevented making progress. This is most noticable as a failure of crashdump kexec, which stops just after issuing: Loading crashdump kernel... to the system console. Two other locations of these loops within the ARM code have been identified and fixed up. Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx> --- arch/arm/kernel/machine_kexec.c | 3 ++- arch/arm/kernel/smp.c | 2 +- arch/arm/mach-omap2/prm_common.c | 2 +- 3 files changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c index 6b38d7a634c1..75d4f5ce6cfd 100644 --- a/arch/arm/kernel/machine_kexec.c +++ b/arch/arm/kernel/machine_kexec.c @@ -91,8 +91,9 @@ void machine_crash_nonpanic_core(void *unused) set_cpu_online(smp_processor_id(), false); atomic_dec(&waiting_for_crash_ipi); + while (1) - cpu_relax(); + cpu_do_idle(); } static void machine_kexec_mask_interrupts(void) diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 5c7ec00a500e..cbaba4a15a3a 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -568,7 +568,7 @@ static void ipi_cpu_stop(unsigned int cpu) local_irq_disable(); while (1) - cpu_relax(); + cpu_do_idle(); } static DEFINE_PER_CPU(struct completion *, cpu_completion); diff --git a/arch/arm/mach-omap2/prm_common.c b/arch/arm/mach-omap2/prm_common.c index 021b5a8b9c0a..d4ddc78b2a0b 100644 --- a/arch/arm/mach-omap2/prm_common.c +++ b/arch/arm/mach-omap2/prm_common.c @@ -523,7 +523,7 @@ void omap_prm_reset_system(void) prm_ll_data->reset_system(); while (1) - cpu_relax(); + cpu_do_idle(); } /** -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
