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Date:   Sun, 4 Jun 2023 15:13:53 -0700
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Subject: Re: [PATCH v8 09/12] x86/cpu: Add a configuration and command line
 option for Key Locker
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To:     Borislav Petkov <bp@alien8.de>
CC:     <linux-kernel@vger.kernel.org>, <linux-crypto@vger.kernel.org>,
        <dm-devel@redhat.com>, <ebiggers@kernel.org>, <elliott@hpe.com>,
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        <lalithambika.krishnakumar@intel.com>, <nhuck@google.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, <linux-doc@vger.kernel.org>
References: <20230524165717.14062-1-chang.seok.bae@intel.com>
 <20230603152227.12335-1-chang.seok.bae@intel.com>
 <20230603152227.12335-10-chang.seok.bae@intel.com>
 <20230603163751.GBZHtsXwW5UUnsSbKX@fat_crate.local>
From:   "Chang S. Bae" <chang.seok.bae@intel.com>
In-Reply-To: <20230603163751.GBZHtsXwW5UUnsSbKX@fat_crate.local>
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On 6/3/2023 9:37 AM, Borislav Petkov wrote:
> On Sat, Jun 03, 2023 at 08:22:24AM -0700, Chang S. Bae wrote:
>> +static __init int x86_nokeylocker_setup(char *arg)
>> +{
>> +	/* Expect an exact match without trailing characters. */
>> +	if (strlen(arg))
>> +		return 0;
>> +
>> +	if (!cpu_feature_enabled(X86_FEATURE_KEYLOCKER))
>> +		return 1;
>> +
>> +	setup_clear_cpu_cap(X86_FEATURE_KEYLOCKER);
>> +	pr_info("x86/keylocker: Disabled by kernel command line.\n");
>> +	return 1;
>> +}
>> +__setup("nokeylocker", x86_nokeylocker_setup);
> 
> Can we stop adding those just to remove them at some point later but
> simply do:
> 
> clearcpuid=keylocker
> 
> ?

Oh, I was not sure about this policy. Thanks, now I'm glad that I have 
confidence in removing this.

Chang