svn commit: r331988 - in stable/11/sys/arm: arm include

[Alexey Dokuchaev]

On Wed, Apr 04, 2018 at 06:11:06AM +0000, Michal Meloun wrote:
> New Revision: 331988
> URL: https://svnweb.freebsd.org/changeset/base/331988
> 
> Log:
>   MFC r328467:
>   
>     Implement mitigation for Spectre version 2 attacks on ARMv7.
> 
> +		case CPU_ARCH_CORTEX_A8:
> +			/*
> +			 * For Cortex-A8, IBE bit must be set otherwise
> +			 * BPIALL is effectively NOP.
> +			 * Unfortunately, Cortex-A is also affected by
> +			 * ARM erratum 687067 which causes non-working
> +			 * BPIALL if IBE bit is set and 'Instruction L1 System
> +			 * Array Debug Register 0' is not 0.
> +			 * This register is not reset on power-up and is
> +			 * accessible only from secure world, so we cannot do
> +			 * nothing (nor detect) to fix this issue.
> +			 * I afraid that on chip ROM based secure monitor on

"I'm afraid", perhaps?

> +		printf("!!!WARNING!!! CPU(%d) is vulnerable to speculative "
> +		    "branch attacks. !!!\n"
> +		    "Qualcomm Krait cores are known (or believed) to be "
> +		    "vulnerable to \n"
> +		    "speculative branch attacks, no mitigation exists yet.\n",
> +		    PCPU_GET(cpuid));
> +		goto unkonown_mitigation;
> +	}  else {
> +		goto unkonown_mitigation;

unkonown? :-)

./danfe