Date: Fri, 5 Jan 2018 14:09:43 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Tim Chen <tim.c.chen@linux.intel.com>
cc: Andy Lutomirski <luto@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Greg KH <gregkh@linuxfoundation.org>,
        Dave Hansen <dave.hansen@intel.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Andi Kleen <ak@linux.intel.com>,
        Arjan Van De Ven <arjan.van.de.ven@intel.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/7] x86/feature: Detect the x86 feature to control
 Speculation
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References: <cover.1515086770.git.tim.c.chen@linux.intel.com> <427aa76dea14532dea7e49f0bce4e7cf1dea7c6f.1515086770.git.tim.c.chen@linux.intel.com>
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On Thu, 4 Jan 2018, Tim Chen wrote:
> +#define MSR_IA32_SPEC_CTRL		0x00000048
> +#define SPEC_CTRL_FEATURE_DISABLE_IBRS	(0 << 0)
> +#define SPEC_CTRL_FEATURE_ENABLE_IBRS	(1 << 0)
> +
> +#define MSR_IA32_PRED_CMD		0x00000049
> +
>  #define MSR_IA32_PERFCTR0		0x000000c1
>  #define MSR_IA32_PERFCTR1		0x000000c2
>  #define MSR_FSB_FREQ			0x000000cd
> @@ -439,6 +445,7 @@
>  #define FEATURE_CONTROL_VMXON_ENABLED_INSIDE_SMX	(1<<1)
>  #define FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX	(1<<2)
>  #define FEATURE_CONTROL_LMCE				(1<<20)
> +#define FEATURE_SET_IBPB				(1<<0)

So how is that bit related to the control bits above? This file is
structured in obvious ways ....

Thanks,

	tglx