Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935486Ab3FTBcU (ORCPT ); Wed, 19 Jun 2013 21:32:20 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:48291 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935297Ab3FTBcS (ORCPT ); Wed, 19 Jun 2013 21:32:18 -0400 Message-ID: <51C25B81.4000502@huawei.com> Date: Thu, 20 Jun 2013 09:31:45 +0800 From: Jianguo Wu User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: =?UTF-8?B?SsO2cm4gRW5nZWw=?= CC: , , Andrew Morton Subject: Re: [PATCH] mmap: allow MAP_HUGETLB for hugetlbfs files v2 References: <1371581225-27535-1-git-send-email-joern@logfs.org> <1371581225-27535-3-git-send-email-joern@logfs.org> <51C107E9.9050900@huawei.com> <20130619162506.GA7511@logfs.org> In-Reply-To: <20130619162506.GA7511@logfs.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.135.74.216] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1713 Lines: 56 Hi Joern, I cannot apply this patch to Linus tree, as the code has been modified since commit af73e4d9506d ("hugetlbfs: fix mmap failure in unaligned size request"). Thanks, Jianguo Wu On 2013/6/20 0:25, Jörn Engel wrote: > It is counterintuitive at best that mmap'ing a hugetlbfs file with > MAP_HUGETLB fails, while mmap'ing it without will a) succeed and b) > return huge pages. > v2: use is_file_hugepages(), as suggested by Jianguo > > Signed-off-by: Joern Engel > Cc: Jianguo Wu > --- > mm/mmap.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/mm/mmap.c b/mm/mmap.c > index 2a594246..cdc8e7a 100644 > --- a/mm/mmap.c > +++ b/mm/mmap.c > @@ -1322,11 +1322,12 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, > > if (!(flags & MAP_ANONYMOUS)) { > audit_mmap_fd(fd, flags); > - if (unlikely(flags & MAP_HUGETLB)) > - return -EINVAL; > file = fget(fd); > if (!file) > goto out; > + retval = -EINVAL; > + if (unlikely(flags & MAP_HUGETLB && !is_file_hugepages(file))) > + goto out_fput; > } else if (flags & MAP_HUGETLB) { > struct user_struct *user = NULL; > /* > @@ -1346,6 +1347,7 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, > flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE); > > retval = vm_mmap_pgoff(file, addr, len, prot, flags, pgoff); > +out_fput: > if (file) > fput(file); > out: -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/