[PATCH 06/14] ARM: spectre-v2: harden branch predictor on context switches

[Vladimir Murzin]

On 16/05/18 12:01, Russell King wrote:
>  __v7_cr7mp_proc_info:
>  	.long	0x410fc170
>  	.long	0xff0ffff0
> -	__v7_proc __v7_cr7mp_proc_info, __v7_cr7mp_setup
> +	__v7_proc __v7_cr7mp_proc_info, __v7_cr7mp_setup, proc_fns = HARDENED_BPIALL_PROCESSOR_FUNCTIONS
>  	.size	__v7_cr7mp_proc_info, . - __v7_cr7mp_proc_info
>  
>  	/*
> @@ -649,7 +700,7 @@ ENDPROC(__v7_setup)
>  __v7_cr8mp_proc_info:
>  	.long	0x410fc180
>  	.long	0xff0ffff0
> -	__v7_proc __v7_cr8mp_proc_info, __v7_cr8mp_setup
> +	__v7_proc __v7_cr8mp_proc_info, __v7_cr8mp_setup, proc_fns = HARDENED_BPIALL_PROCESSOR_FUNCTIONS
>  	.size	__v7_cr8mp_proc_info, . - __v7_cr8mp_proc_info

For R-class cores, the mitigation doesn't make much sense since we do not enforce user/kernel
isolation anyway. I believe the same also applies to A-class cores built with !MMU, so you might
want to guard CPU_SPECTRE with MMU in PATCH 05/14.

Cheers
Vladimir