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Date:   Thu, 25 Jan 2018 12:50:16 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     David Woodhouse <dwmw2@infradead.org>
Cc:     arjan@linux.intel.com, tglx@linutronix.de, karahmed@amazon.de,
        x86@kernel.org, linux-kernel@vger.kernel.org,
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        torvalds@linux-foundation.org, gregkh@linux-foundation.org,
        dave.hansen@intel.com, gnomes@lxorguk.ukuu.org.uk,
        ashok.raj@intel.com, mingo@kernel.org
Subject: Re: [PATCH v4 7/7] x86/speculation: Add basic IBPB (Indirect Branch
 Prediction Barrier) support
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On Thu, Jan 25, 2018 at 11:47:35AM +0000, David Woodhouse wrote:
> I did already do the explicit clobbers now you reminded me how to do
> them, but I elected not to use ASM_NO_INPUT_CLOBBER() because on
> balance, losing the MSR_IA32_PRED_CMD / PRED_CMD_IBPB definitions and
> having to hard-code the numbers was not so much of a win.

and I'm thinking exactly the opposite: if an alternative can lose a
bunch of inputs which don't change, then that's a good thing.

-- 
Regards/Gruss,
    Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.