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Date: Tue, 25 Jun 2013 14:18:16 +0530
From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
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To: Michael Neuling <mikey@neuling.org>
Subject: Re: [PATCH 1/2] powerpc/hw_brk: Fix setting of length for exact mode
 breakpoints
References: <1372052843-19109-1-git-send-email-mikey@neuling.org>
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Cc: linuxppc-dev@lists.ozlabs.org,
 Edjunior Barbosa Machado <emachado@linux.vnet.ibm.com>
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On 06/24/2013 11:17 AM, Michael Neuling wrote:
> The smallest match region for both the DABR and DAWR is 8 bytes, so the
> kernel needs to filter matches when users want to look at regions smaller than
> this.
> 
> Currently we set the length of PPC_BREAKPOINT_MODE_EXACT breakpoints to 8.
> This is wrong as in exact mode we should only match on 1 address, hence the
> length should be 1.
> 
> This ensures that the kernel will filter out any exact mode hardware breakpoint
> matches on any addresses other than the requested one.
> 
> Signed-off-by: Michael Neuling <mikey@neuling.org>

Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>