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From: Rasmus Villemoes <linux@rasmusvillemoes.dk>
To: Mike Snitzer <snitzer@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
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        "Martin K. Petersen" <martin.petersen@oracle.com>,
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        Jens Axboe <axboe@kernel.dk>
Subject: Re: [PATCH 2/2] lib/lcm.c: lcm(n,0)=lcm(0,n) is 0, not n
Organization: D03
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Date: Mon, 30 Mar 2015 21:38:27 +0200
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	(Mike Snitzer's message of "Sat, 28 Mar 2015 22:44:28 -0400")
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On Sun, Mar 29 2015, Mike Snitzer <snitzer@redhat.com> wrote:

> On Tue, Dec 9, 2014 at 4:03 PM, Rasmus Villemoes
> <linux@rasmusvillemoes.dk> wrote:
>> Return the mathematically correct answer when an argument is 0.
>>
>> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
>
> This change is the source of 3.19 regression for stacking device
> limits, via commit 69c953c ("lib/lcm.c: lcm(n,0)=lcm(0,n) is 0, not
> n").
>
>
> Rasmus, mathematical purity of lcm() aside, it'd have been nice if you
> looked at the lcm() callers to determine whether you'd be breaking
> them.

I'm sorry about this. I thought I did check the callers, but evidently
not well enough.

Rasmus