linux-kernel - Re: [Xen-devel] [PATCH v2] xen/x86: Zero out .bss for PV guests

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Message-ID: <56CDECE3.7020602@oracle.com>
Date:	Wed, 24 Feb 2016 12:48:19 -0500
From:	Boris Ostrovsky <boris.ostrovsky@...cle.com>
To:	Andrew Cooper <andrew.cooper3@...rix.com>, konrad.wilk@...cle.com,
	david.vrabel@...rix.com
Cc:	xen-devel@...ts.xenproject.org, mcgrof@...nel.org,
	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Subject: Re: [Xen-devel] [PATCH v2] xen/x86: Zero out .bss for PV guests

On 02/24/2016 12:26 PM, Andrew Cooper wrote:
> On 24/02/16 15:19, Boris Ostrovsky wrote:
>> +	/* Clear .bss */
>> +	xor REG(ax),REG(ax)
> If we are nitpicking,
>
> This should be xor %eax, %eax even in 64bit.  Functionally identical,
> and shorter to encode.

Right, Brian Gerst pointed this out too in another message.

-boris