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Date:   Mon, 27 Jul 2020 17:36:31 -0700
From:   Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
To:     peterz@infradead.org
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>, Borislav Petkov <bp@suse.de>,
        Andy Lutomirski <luto@kernel.org>, x86@kernel.org,
        Dave Hansen <dave.hansen@intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Cathy Zhang <cathy.zhang@intel.com>,
        Fenghua Yu <fenghua.yu@intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Kyung Min Park <kyung.min.park@intel.com>,
        "Ravi V. Shankar" <ravi.v.shankar@intel.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        linux-kernel@vger.kernel.org,
        Ricardo Neri <ricardo.neri@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        linux-edac@vger.kernel.org
Subject: Re: [PATCH 4/4] x86/cpu: Use SERIALIZE in sync_core() when available
Message-ID: <20200728003631.GB23421@ranerica-svr.sc.intel.com>
References: <20200727043132.15082-1-ricardo.neri-calderon@linux.intel.com>
 <20200727043132.15082-5-ricardo.neri-calderon@linux.intel.com>
 <20200727082003.GD119549@hirez.programming.kicks-ass.net>
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On Mon, Jul 27, 2020 at 10:20:03AM +0200, peterz@infradead.org wrote:
> On Sun, Jul 26, 2020 at 09:31:32PM -0700, Ricardo Neri wrote:
> > +static inline void serialize(void)
> > +{
> > +	asm volatile(".byte 0xf, 0x1, 0xe8");
> > +}
> 
> Can we pretty please have a comment with the binutils version that has
> the mnomic? Such that when we increase the required binutils version we
> can grep for this.

This is supported since binutils 2.35[1]. I'll add a comment with the
clarification.

Thanks and BR,
Ricardo

[1]. https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=blob_plain;f=gas/NEWS;;hb=refs/tags/binutils-2_35