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Subject: Re: [PATCH RFC v2 1/6] x86: Skip PTI when disable indication is set
To: Nadav Amit <namit@vmware.com>, Ingo Molnar <mingo@redhat.com>
References: <20180215163602.61162-1-namit@vmware.com>
 <20180215163602.61162-2-namit@vmware.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
        Andy Lutomirski <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, Willy Tarreau <w@1wt.eu>,
        Nadav Amit <nadav.amit@gmail.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org
From: Dave Hansen <dave.hansen@linux.intel.com>
Message-ID: <7057a6cc-f3ea-8826-5440-61e0154950da@linux.intel.com>
Date: Thu, 15 Feb 2018 10:10:19 -0800
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On 02/15/2018 08:35 AM, Nadav Amit wrote:
> +.Lno_spec_\@:
> +	lfence
> +	jmp	.Lend_\@
> +
>  .Lnoflush_\@:
>  	SET_NOFLUSH_BIT \save_reg
>  

How expensive is this?