diff options
Diffstat (limited to 'arch/arm/kernel/traps.c')
| -rw-r--r-- | arch/arm/kernel/traps.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index c8e4bb714944..58348631671d 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -25,6 +25,7 @@ #include <linux/delay.h> #include <linux/init.h> #include <linux/sched.h> +#include <linux/irq.h> #include <linux/atomic.h> #include <asm/cacheflush.h> @@ -467,6 +468,31 @@ asmlinkage void do_unexp_fiq (struct pt_regs *regs) } /* + * Handle FIQ similarly to NMI on x86 systems. + * + * The runtime environment for NMIs is extremely restrictive + * (NMIs can pre-empt critical sections meaning almost all locking is + * forbidden) meaning this default FIQ handling must only be used in + * circumstances where non-maskability improves robustness, such as + * watchdog or debug logic. + * + * This handler is not appropriate for general purpose use in drivers + * platform code and can be overrideen using set_fiq_handler. + */ +asmlinkage void __exception_irq_entry handle_fiq_as_nmi(struct pt_regs *regs) +{ + struct pt_regs *old_regs = set_irq_regs(regs); + + nmi_enter(); + + /* nop. FIQ handlers for special arch/arm features can be added here. */ + + nmi_exit(); + + set_irq_regs(old_regs); +} + +/* * bad_mode handles the impossible case in the vectors. If you see one of * these, then it's extremely serious, and could mean you have buggy hardware. * It never returns, and never tries to sync. We hope that we can at least |