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Message-ID: <4EC61DB1.3090608@mvista.com>
Date:   Fri, 18 Nov 2011 12:56:17 +0400
From:   Sergei Shtylyov <sshtylyov@mvista.com>
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To:     David Daney <ddaney.cavm@gmail.com>
CC:     linux-mips@linux-mips.org, ralf@linux-mips.org,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, David Daney <david.daney@cavium.com>,
        David Rientjes <rientjes@google.com>
Subject: Re: [PATCH v2 2/2] hugetlb: Provide safer dummy values for HPAGE_MASK
 and HPAGE_SIZE
References: <1321567050-13197-1-git-send-email-ddaney.cavm@gmail.com> <1321567050-13197-3-git-send-email-ddaney.cavm@gmail.com>
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Hello.

On 18-11-2011 1:57, David Daney wrote:

> From: David Daney<david.daney@cavium.com>

> It was pointed out by David Rientjes that the dummy values for
> HPAGE_MASK and HPAGE_SIZE are quite unsafe.  It they are inadvertently
> used with !CONFIG_HUGETLB_PAGE, compilation would succeed, but the
> resulting code would surly not do anything sensible.
>
> Place BUG() in the these dummy definitions, as we do in similar
> circumstances in other places, so any abuse can be easily detected.
>
> Since the only sane place to use these symbols when
> !CONFIG_HUGETLB_PAGE is on dead code paths, the BUG() cause any actual
> code to be emitted by the compiler.

    You mean "doesn't cause"?

> Cc: David Rientjes<rientjes@google.com>
> Signed-off-by: David Daney<david.daney@cavium.com>

WBR, Sergei