Date: Tue, 11 Nov 2014 20:46:21 +0100
From: Borislav Petkov <bp@alien8.de>
To: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: linux-kernel@vger.kernel.org, H Peter Anvin <h.peter.anvin@intel.com>,
        Ingo Molnar <mingo@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
        David Airlie <airlied@linux.ie>, dri-devel@lists.freedesktop.org,
        x86@kernel.org
Subject: Re: [PATCH 3/6] x86: Add support for the clwb instruction
Message-ID: <20141111194621.GB12555@pd.tnic>
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On Tue, Nov 11, 2014 at 12:40:00PM -0700, Ross Zwisler wrote:
> Yep, it's weird, I know.  :)

But sure, saving opcode space, makes sense to me.

Btw, I'd still be interested about this:

> +static inline void clwb(volatile void *__p)
> +{
> +     alternative_io_2(".byte " __stringify(NOP_DS_PREFIX) "; clflush %P0",

Any particular reason for using 0x3e as a prefix to have the insns be
the same size or is it simply because CLFLUSH can stomach it?

Thanks.

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
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