[PATCH] ARM: kprobes: Eliminate test code's use of BX instruction on ARMv4 CPUs

[Russell King - ARM Linux]

On Mon, Jan 19, 2015 at 05:18:50PM +0000, Jon Medhurst (Tixy) wrote:
> diff --git a/arch/arm/probes/kprobes/test-arm.c b/arch/arm/probes/kprobes/test-arm.c
> index e72b07e..5c6e37e 100644
> --- a/arch/arm/probes/kprobes/test-arm.c
> +++ b/arch/arm/probes/kprobes/test-arm.c
> @@ -215,9 +215,11 @@ void kprobe_arm_test_cases(void)
>  	TEST_UNSUPPORTED("msr	cpsr_f, lr")
>  	TEST_UNSUPPORTED("msr	spsr, r0")
>  
> +#if (__LINUX_ARM_ARCH__ >= 5) || defined(CONFIG_CPU_32v4T)
>  	TEST_BF_R("bx	r",0,2f,"")
>  	TEST_BB_R("bx	r",7,2f,"")
>  	TEST_BF_R("bxeq	r",14,2f,"")
> +#endif

Unnecessary ()... and this isn't correct.  With a multi-platform kernel, we
can end up with CONFIG_CPU_32v4 and CONFIG_CPU_32v4T both set.

I think:

#if __LINUX_ARM_ARCH__ >= 5 || \
    (__LINUX_ARM_ARCH__ == 4 && !defined(CONFIG_CPU_32v4))

would cover it.

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