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Date: Wed, 9 Oct 2013 11:53:57 +0100
From: Will Deacon <will.deacon@arm.com>
To: "Wang, Yalin" <Yalin.Wang@sonymobile.com>
Cc: "'linux-arm-msm-owner@vger.kernel.org'" 
	<linux-arm-msm-owner@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: SDIV / UDIV  Question
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On Wed, Oct 09, 2013 at 08:08:05AM +0100, Wang, Yalin wrote:
> I have a question about sdiv/ udiv  instructions :
> In  armv7 A/R  TRM, it said sdiv/udiv will cause 
> Divide by zero as undefined exception or just return zero
> (decided by implementation) .
> 
> So  in kernel ,  should we need register a undef hook to 
> Get this undef exception and send SIGFPE to user space
> Process ?  

As far as I can see, this can only happen for R-class cores,
based on SCTLR.DZ.

Will