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Date: Tue, 3 Oct 2017 19:44:48 +0300
From: "Kirill A. Shutemov" <kirill@shutemov.name>
To: Zi Yan <zi.yan@sent.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
 "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
 Abdul Haleem <abdhalee@linux.vnet.ibm.com>,
 Anshuman Khandual <khandual@linux.vnet.ibm.com>,
 Zi Yan <zi.yan@cs.rutgers.edu>, Andrew Morton <akpm@linux-foundation.org>,
 linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH] mm: remove unnecessary WARN_ONCE in
 page_vma_mapped_walk().
Message-ID: <20171003164448.gasvu5iu3xaoscgo@node.shutemov.name>
References: <20171003142606.12324-1-zi.yan@sent.com>
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On Tue, Oct 03, 2017 at 10:26:06AM -0400, Zi Yan wrote:
> From: Zi Yan <zi.yan@cs.rutgers.edu>
> 
> A non present pmd entry can appear after pmd_lock is taken in
> page_vma_mapped_walk(), even if THP migration is not enabled.
> The WARN_ONCE is unnecessary.
> 
> Fixes: 616b8371539a ("mm: thp: enable thp migration in generic path")
> Reported-and-tested-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
> Signed-off-by: Zi Yan <zi.yan@cs.rutgers.edu>
> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>

Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>

-- 
 Kirill A. Shutemov