diff options
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/include/asm/irqflags.h | 34 | ||||
| -rw-r--r-- | arch/arm64/kernel/debug-monitors.c | 5 |
2 files changed, 16 insertions, 23 deletions
diff --git a/arch/arm64/include/asm/irqflags.h b/arch/arm64/include/asm/irqflags.h index 8c581281fa12..9ecdca7011f0 100644 --- a/arch/arm64/include/asm/irqflags.h +++ b/arch/arm64/include/asm/irqflags.h @@ -21,6 +21,19 @@ #include <asm/ptrace.h> /* + * Aarch64 has flags for masking: Debug, Asynchronous (serror), Interrupts and + * FIQ exceptions, in the 'daif' register. We mask and unmask them in 'dai' + * order: + * Masking debug exceptions causes all other exceptions to be masked too/ + * Masking SError masks irq, but not debug exceptions. Masking irqs has no + * side effects for other flags. Keeping to this order makes it easier for + * entry.S to know which exceptions should be unmasked. + * + * FIQ is never expected, but we mask it when we disable debug exceptions, and + * unmask it at all other times. + */ + +/* * CPU interrupt mask handling. */ static inline unsigned long arch_local_irq_save(void) @@ -89,26 +102,5 @@ static inline int arch_irqs_disabled_flags(unsigned long flags) { return flags & PSR_I_BIT; } - -/* - * save and restore debug state - */ -#define local_dbg_save(flags) \ - do { \ - typecheck(unsigned long, flags); \ - asm volatile( \ - "mrs %0, daif // local_dbg_save\n" \ - "msr daifset, #8" \ - : "=r" (flags) : : "memory"); \ - } while (0) - -#define local_dbg_restore(flags) \ - do { \ - typecheck(unsigned long, flags); \ - asm volatile( \ - "msr daif, %0 // local_dbg_restore\n" \ - : : "r" (flags) : "memory"); \ - } while (0) - #endif #endif diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c index c7ef99904934..a88b6ccebbb4 100644 --- a/arch/arm64/kernel/debug-monitors.c +++ b/arch/arm64/kernel/debug-monitors.c @@ -30,6 +30,7 @@ #include <asm/cpufeature.h> #include <asm/cputype.h> +#include <asm/daifflags.h> #include <asm/debug-monitors.h> #include <asm/system_misc.h> @@ -46,9 +47,9 @@ u8 debug_monitors_arch(void) static void mdscr_write(u32 mdscr) { unsigned long flags; - local_dbg_save(flags); + flags = local_daif_save(); write_sysreg(mdscr, mdscr_el1); - local_dbg_restore(flags); + local_daif_restore(flags); } NOKPROBE_SYMBOL(mdscr_write); |