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From: Peter Grehan <grehan@freebsd.org>
Subject: Re: svn commit: r247871 - head/usr.sbin/bhyve
To: "Colin Percival" <cperciva@freebsd.org>,
 "David Malone" <dwmalone@maths.tcd.ie>
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Date: Thu,  7 Mar 2013 09:33:00 +1000 (EST)
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>On 03/06/13 15:16, David Malone wrote:
>>> +	/*
>>> +	 * We're just computing (a-b) in GF(216).
>> 
>>> +	ndesc = (unsigned)*hq->hq_avail_idx - (unsigned)hq->hq_cur_aidx;
>> 
>> I think the comment here is wrong? Subtraction (and addition) in
>> GF(2^16) is just xor of 16 bit numbers. You seem to actually be
>> working in Z(2^16), where subtraction is normal subtraction mod
>> 65536.
>
>Given that there's no such thing as GF(216) due to 216 = 2^3 * 3^3 not
>being a prime power, the comment is definitely wrong. ;-)

 Any suggestions for better wording ? I submitted the comment block unchanged from the patch.

later,

Peter.

later,

Peter.