From b3bf6aa7e79117419f7eddccf0b7af4382d823c3 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Thu, 21 Nov 2013 14:46:17 +0000 Subject: [PATCH] arm64: Unmask asynchronous aborts when in kernel mode The asynchronous aborts are generally fatal for the kernel but they can be masked via the pstate A bit. If a system error happens while in kernel mode, it won't be visible until returning to user space. This patch enables this kind of abort early to help identifying the cause. Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/irqflags.h | 3 +++ arch/arm64/kernel/setup.c | 5 +++++ arch/arm64/kernel/smp.c | 1 + 3 files changed, 9 insertions(+) diff --git a/arch/arm64/include/asm/irqflags.h b/arch/arm64/include/asm/irqflags.h index aa11943b8502..b2fcfbc51ecc 100644 --- a/arch/arm64/include/asm/irqflags.h +++ b/arch/arm64/include/asm/irqflags.h @@ -56,6 +56,9 @@ static inline void arch_local_irq_disable(void) #define local_fiq_enable() asm("msr daifclr, #1" : : : "memory") #define local_fiq_disable() asm("msr daifset, #1" : : : "memory") +#define local_async_enable() asm("msr daifclr, #4" : : : "memory") +#define local_async_disable() asm("msr daifset, #4" : : : "memory") + /* * Save the current interrupt enable state. */ diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 0bc5e4cbc017..bd9bbd0e44ed 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -205,6 +205,11 @@ u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID }; void __init setup_arch(char **cmdline_p) { + /* + * Unmask asynchronous aborts early to catch possible system errors. + */ + local_async_enable(); + setup_processor(); setup_machine_fdt(__fdt_pointer); diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index a5aeefab03c3..a0c2ca602cf8 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -160,6 +160,7 @@ asmlinkage void secondary_start_kernel(void) local_irq_enable(); local_fiq_enable(); + local_async_enable(); /* * OK, it's off to the idle thread for us -- 2.39.5