Date: Tue, 11 Aug 2015 14:33:33 +0800
From: Baoquan He <bhe@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: ebiederm@xmission.com, vgoyal@redhat.com, dyoung@redhat.com,
        mhuang@redhat.com, lisa.mitchell@hp.com, tatsu@ab.jp.nec.com,
        seiji.aguchi.tr@hitachi.com, linux-kernel@vger.kernel.org,
        kexec@lists.infradead.org
Subject: Re: [Patch v2] align crash_notes allocation to make it be inside one
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Hi Andrew,

On 08/03/15 at 03:04pm, Andrew Morton wrote:
> On Mon,  3 Aug 2015 20:50:43 +0800 Baoquan He <bhe@redhat.com> wrote:
> And I think the WARN_ON can be replaced with a
> BUILD_BUG_ON(sizeof>PAGE_SIZE)?  That would avoid adding runtime
> overhead.

Rethink about this, you are right. Using BUILD_BUG_ON is better.
Anyone who found this compiling break should check if his/her code
changes increase the crash_notes size. If possible that increase need be
avoidable. Otherwise he should report this to upstream why it's
unavoidable to increase crash_notes size, then let's consider the
redesign the crash_notes data structure. 

So I will use BUILD_BUG_ON and repost.

Thanks
Baoquan
> 
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