Re: [PATCH v4 2/8] arm64: irqflags: Pass flags as readonly operand to restore instruction

From: Mark Rutland
Date: Tue Jun 11 2019 - 08:51:15 EST


On Tue, Jun 11, 2019 at 10:38:07AM +0100, Julien Thierry wrote:
> Flags are only read by the instructions doing the irqflags restore
> operation. Pass the operand as read only to the asm inline instead of
> read-write.
>
> Signed-off-by: Julien Thierry <julien.thierry@xxxxxxx>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will.deacon@xxxxxxx>

Acked-by: Mark Rutland <mark.rutland@xxxxxx>

Mark.

> ---
> arch/arm64/include/asm/irqflags.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/include/asm/irqflags.h b/arch/arm64/include/asm/irqflags.h
> index 62996318..9c93152 100644
> --- a/arch/arm64/include/asm/irqflags.h
> +++ b/arch/arm64/include/asm/irqflags.h
> @@ -119,8 +119,8 @@ static inline void arch_local_irq_restore(unsigned long flags)
> __msr_s(SYS_ICC_PMR_EL1, "%0")
> "dsb sy",
> ARM64_HAS_IRQ_PRIO_MASKING)
> - : "+r" (flags)
> :
> + : "r" (flags)
> : "memory");
> }
>
> --
> 1.9.1