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Subject: Re: [BUG linux-next] Kernel panic found with linux-next-20160414
To: Hugh Dickins <hughd@google.com>, "Shi, Yang" <yang.shi@linaro.org>
References: <5716C29F.1090205@linaro.org>
 <alpine.LSU.2.11.1604200041460.3009@eggly.anvils>
 <5717AA46.5020905@linaro.org>
 <alpine.LSU.2.11.1604270029350.7066@eggly.anvils>
Cc: Andrew Morton <akpm@linux-foundation.org>, sfr@canb.auug.org.au,
        LKML <linux-kernel@vger.kernel.org>, linux-mm@kvack.org
From: Vlastimil Babka <vbabka@suse.cz>
Message-ID: <57207D88.4000508@suse.cz>
Date: Wed, 27 Apr 2016 10:51:20 +0200
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On 04/27/2016 10:14 AM, Hugh Dickins wrote:
> It's rather horrible that compaction.c uses functions in page_alloc.c
> which skip doing some of the things we expect to be done: the non-debug
> preparation tends to get noticed, but the debug options overlooked.
> We can expect more problems of this kind in future: someone will add
> yet another debug prep line in page_alloc.c, and at first nobody will
> notice that it's also needed in compaction.c.

Point taken, I'll try to come up with more maintainable solution next 
time I attempt the isolate_freepages_direct() approach. Sorry about the 
troubles.