Re: [PATCH 22/35] arm64: mte: Enable in-kernel MTE

[Catalin Marinas]

On Fri, Aug 14, 2020 at 07:27:04PM +0200, Andrey Konovalov wrote:
> diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
> index 4d3abb51f7d4..4d94af19d8f6 100644
> --- a/arch/arm64/kernel/cpufeature.c
> +++ b/arch/arm64/kernel/cpufeature.c
> @@ -1670,6 +1670,9 @@ static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
>  	write_sysreg_s(0, SYS_TFSR_EL1);
>  	write_sysreg_s(0, SYS_TFSRE0_EL1);
>  
> +	/* Enable Match-All at EL1 */
> +	sysreg_clear_set(tcr_el1, 0, SYS_TCR_EL1_TCMA1);
> +
>  	/*
>  	 * CnP must be enabled only after the MAIR_EL1 register has been set
>  	 * up. Inconsistent MAIR_EL1 between CPUs sharing the same TLB may
> @@ -1687,6 +1690,9 @@ static void cpu_enable_mte(struct arm64_cpu_capabilities const *cap)
>  	mair &= ~MAIR_ATTRIDX(MAIR_ATTR_MASK, MT_NORMAL_TAGGED);
>  	mair |= MAIR_ATTRIDX(MAIR_ATTR_NORMAL_TAGGED, MT_NORMAL_TAGGED);
>  	write_sysreg_s(mair, SYS_MAIR_EL1);
> +
> +	/* Enable MTE Sync Mode for EL1 */
> +	sysreg_clear_set(sctlr_el1, SCTLR_ELx_TCF_MASK, SCTLR_ELx_TCF_SYNC);

In the 8th incarnation of the user MTE patches, this initialisation
moved to proc.S before the MMU is initialised. When rebasing, please
take this into account.

-- 
Catalin