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Subject: Re: [PATCH] memory-hotplug: Fix bad area access on
 dissolve_free_huge_pages()
To: Rui Teng <rui.teng@linux.vnet.ibm.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
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Cc: Andrew Morton <akpm@linux-foundation.org>,
        Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
        Michal Hocko <mhocko@suse.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>,
        Paul Gortmaker <paul.gortmaker@windriver.com>,
        Santhosh G <santhog4@in.ibm.com>
From: Dave Hansen <dave.hansen@linux.intel.com>
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Date: Wed, 14 Sep 2016 09:37:03 -0700
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On 09/14/2016 09:33 AM, Rui Teng wrote:
> 
> How about return the size of page freed from dissolve_free_huge_page(),
> and jump such step on pfn?

That would be a nice improvement.

But, as far as describing the initial problem, can you explain how the
tail pages still ended up being PageHuge()?  Seems like dissolving the
huge page should have cleared that.