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Subject: Re: [PATCH v2 4/8] x86/spec_ctrl: Add sysctl knobs to enable/disable
 SPEC_CTRL feature
To: "Van De Ven, Arjan" <arjan.van.de.ven@intel.com>,
        Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
        Andy Lutomirski <luto@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Greg KH <gregkh@linuxfoundation.org>,
        "Hansen, Dave" <dave.hansen@intel.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Andi Kleen <ak@linux.intel.com>,
        David Woodhouse <dwmw@amazon.co.uk>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
References: <cover.1515204614.git.tim.c.chen@linux.intel.com>
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 <0575AF4FD06DD142AD198903C74E1CC87A56EF1A@ORSMSX103.amr.corp.intel.com>
From: Tim Chen <tim.c.chen@linux.intel.com>
Message-ID: <1273a895-6a8c-dc62-3b8d-a83c37c2c89d@linux.intel.com>
Date: Mon, 8 Jan 2018 09:02:22 -0800
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On 01/08/2018 07:29 AM, Van De Ven, Arjan wrote:
>>> +	if ((!c->cpu_index) && (boot_cpu_has(X86_FEATURE_SPEC_CTRL))) {
>>
>> We should test X86_BUG_SPECTRE_V1 here too before default enabling this,
>> no?
> 
> 
> we shouldn't default enable this.
> 

Patch 7 disables ibrs if retpoline is in use.

Tim