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Date:   Tue, 09 Aug 2022 07:08:07 +0100
From:   Marc Zyngier <maz@kernel.org>
To:     Zenghui Yu <yuzenghui@huawei.com>
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        catalin.marinas@arm.com, will@kernel.org,
        wanghaibin.wang@huawei.com, Shreyas K K <quic_shrekk@quicinc.com>
Subject: Re: [PATCH] arm64: Fix match_list for erratum 1286807 on Arm
 Cortex-A76
In-Reply-To: <20220809043848.969-1-yuzenghui@huawei.com>
References: <20220809043848.969-1-yuzenghui@huawei.com>
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On 2022-08-09 05:38, Zenghui Yu wrote:
> Since commit 51f559d66527 ("arm64: Enable repeat tlbi workaround on 
> KRYO4XX
> gold CPUs"), we failed to detect erratum 1286807 on Cortex-A76 because 
> its
> entry in arm64_repeat_tlbi_list[] was accidently corrupted by this 
> commit.
> 
> Fix this issue by creating a separate entry for Kryo4xx Gold.
> 
> Fixes: 51f559d66527 ("arm64: Enable repeat tlbi workaround on KRYO4XX
> gold CPUs")
> Cc: Shreyas K K <quic_shrekk@quicinc.com>
> Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
> ---
>  arch/arm64/kernel/cpu_errata.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm64/kernel/cpu_errata.c 
> b/arch/arm64/kernel/cpu_errata.c
> index 7e6289e709fc..0f7e9087d900 100644
> --- a/arch/arm64/kernel/cpu_errata.c
> +++ b/arch/arm64/kernel/cpu_errata.c
> @@ -208,6 +208,8 @@ static const struct arm64_cpu_capabilities
> arm64_repeat_tlbi_list[] = {
>  #ifdef CONFIG_ARM64_ERRATUM_1286807
>  	{
>  		ERRATA_MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 3, 0),
> +	},
> +	{
>  		/* Kryo4xx Gold (rcpe to rfpe) => (r0p0 to r3p0) */
>  		ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe),
>  	},

Ouch. It isn't the first time we end-up with this sort
of thing, and I wonder whether we should restructure
the ERRATA_MIDR_* macros to prevent this sort of
accidental override...

Anyway, thanks for spotting it!

Cc: stable@vger.kernel.org
Acked-by: Marc Zyngier <maz@kernel.org>

         M.
-- 
Jazz is not dead. It just smells funny...