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Subject: Re: [Xen-devel] [PATCH v2] xen/x86: Zero out .bss for PV guests
To: Andrew Cooper <andrew.cooper3@citrix.com>, konrad.wilk@oracle.com,
        david.vrabel@citrix.com
References: <1456327186-27354-1-git-send-email-boris.ostrovsky@oracle.com>
 <56CDE7D9.6000209@citrix.com>
Cc: xen-devel@lists.xenproject.org, mcgrof@kernel.org,
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From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Message-ID: <56CDECE3.7020602@oracle.com>
Date: Wed, 24 Feb 2016 12:48:19 -0500
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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