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Date:   Tue, 10 Oct 2023 21:42:52 -0700
From:   Josh Poimboeuf <jpoimboe@kernel.org>
To:     Breno Leitao <leitao@debian.org>
Cc:     tglx@linutronix.de, bp@alien8.de, Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Pawan Gupta <pawan.kumar.gupta@linux.intel.com>, leit@meta.com,
        "open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)" 
        <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v4] x86/bugs: Add a separate config for each mitigation
Message-ID: <20231011044252.42bplzjsam3qsasz@treble>
References: <20231010103028.4192223-1-leitao@debian.org>
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On Tue, Oct 10, 2023 at 03:30:27AM -0700, Breno Leitao wrote:
> +config MITIGATE_MDS
> +	bool "Mitigate Microarchitectural Data Sampling (MDS) hardware bug"
> +	depends on CPU_SUP_INTEL
> +	default y
> +	help
> +	  Enable mitigation for Microarchitectural Data Sampling (MDS). MDS is
> +	  a hardware vulnerability which allows unprivileged speculative access
> +	  to data which is available in various CPU internal buffer. Deeper
> +	  technical information is available in the MDS specific x86 architecture
> +	  section: Documentation/arch/x86/mds.rst.

MITIGATE_GDS seems to be missing?

For consistency I'm thinking it would be better to call them
MITIGATION_* rather than MITIGATE_* since they're under the
SPECULATION_MITIGATIONS menuentry, and the bugs code almost exclusively
uses the noun "mitigation" rather than the verb "mitigate".

While we're at it should we go ahead and rename the existing options?

e.g.:

  MITIGATION_PAGE_TABLE_ISOLATION
  MITIGATION_RETPOLINE
  MITIGATION_UNRET_ENTRY
  MITIGATION_CALL_DEPTH_TRACKING
  MITIGATION_IBPB_ENTRY
  MITIGATION_IBRS_ENTRY
  MITIGATION_SRSO
  MITIGATION_SLS

-- 
Josh