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Date: Tue, 13 Sep 2016 12:32:58 +0300
From: "Kirill A. Shutemov" <kirill@shutemov.name>
To: Rui Teng <rui.teng@linux.vnet.ibm.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Michal Hocko <mhocko@suse.com>,
        Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
        Chen Gang <chengang@emindsoft.com.cn>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>,
        hejianet@linux.vnet.ibm.com
Subject: Re: [RFC] mm: Change the data type of huge page size from unsigned
 long to u64
Message-ID: <20160913093257.GA31186@node>
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On Tue, Sep 13, 2016 at 05:26:05PM +0800, Rui Teng wrote:
> The huge page size could be 16G(0x400000000) on ppc64 architecture, and it will
> cause an overflow on unsigned long data type(0xFFFFFFFF).

Huh? ppc64 is 64-bit system and sizeof(void *) is equal to
sizeof(unsigned long) on Linux (LP64 model).

So where your 0xFFFFFFFF comes from?

-- 
 Kirill A. Shutemov