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From:   Thomas Gleixner <tglx@linutronix.de>
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To:     Breno Leitao <leitao@debian.org>, bp@alien8.de,
        pawan.kumar.gupta@linux.intel.com, paul@paul-moore.com
Cc:     leit@meta.com, x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] cpu/bugs: Disable CPU mitigations at compilation time
In-Reply-To: <20230203120615.1121272-1-leitao@debian.org>
References: <20230203120615.1121272-1-leitao@debian.org>
Date:   Sun, 11 Jun 2023 00:37:34 +0200
Message-ID: <87352z7xld.ffs@tglx>
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On Fri, Feb 03 2023 at 04:06, Breno Leitao wrote:
> Right now it is not possible to disable CPU vulnerabilities mitigations
> at build time. Mitigation needs to be disabled passing kernel
> parameters, such as 'mitigations=off'.
>
> Create a new config option (CONFIG_CPU_MITIGATIONS_DEFAULT_OFF) that
> sets the global variable `cpu_mitigations` to OFF, instead of AUTO. This
> allows the creation of kernel binaries that boots with the CPU
> mitigations turned off by default, and does not require dealing kernel
> parameters.

Why? What's the justification

Just because we do not have not enough kernel config items yet, does not
count.

Thanks,

        tglx