From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932536Ab2C1LgC (ORCPT ); Wed, 28 Mar 2012 07:36:02 -0400 Received: from e23smtp04.au.ibm.com ([202.81.31.146]:46746 "EHLO e23smtp04.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932365Ab2C1LgA (ORCPT ); Wed, 28 Mar 2012 07:36:00 -0400 From: "Aneesh Kumar K.V" To: Michal Hocko Cc: linux-mm@kvack.org, mgorman@suse.de, kamezawa.hiroyu@jp.fujitsu.com, dhillf@gmail.com, aarcange@redhat.com, akpm@linux-foundation.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Subject: Re: [PATCH -V4 02/10] hugetlbfs: don't use ERR_PTR with VM_FAULT* values In-Reply-To: <20120328092547.GC20949@tiehlicka.suse.cz> References: <1331919570-2264-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1331919570-2264-3-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <20120328092547.GC20949@tiehlicka.suse.cz>User-Agent: Notmuch/0.11.1+346~g13d19c3 (http://notmuchmail.org) Emacs/23.3.1 (x86_64-pc-linux-gnu) Date: Wed, 28 Mar 2012 17:05:49 +0530 Message-ID: <87vclpyn3e.fsf@skywalker.in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii x-cbid: 12032801-9264-0000-0000-0000012461BA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Michal Hocko writes: > On Fri 16-03-12 23:09:22, Aneesh Kumar K.V wrote: >> From: "Aneesh Kumar K.V" >> >> Using VM_FAULT_* codes with ERR_PTR will require us to make sure >> VM_FAULT_* values will not exceed MAX_ERRNO value. >> >> Signed-off-by: Aneesh Kumar K.V >> --- >> mm/hugetlb.c | 18 +++++++++++++----- >> 1 files changed, 13 insertions(+), 5 deletions(-) >> >> diff --git a/mm/hugetlb.c b/mm/hugetlb.c >> index d623e71..3782da8 100644 >> --- a/mm/hugetlb.c >> +++ b/mm/hugetlb.c > [...] >> @@ -1047,7 +1047,7 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma, >> page = alloc_buddy_huge_page(h, NUMA_NO_NODE); >> if (!page) { >> hugetlb_put_quota(inode->i_mapping, chg); >> - return ERR_PTR(-VM_FAULT_SIGBUS); >> + return ERR_PTR(-ENOSPC); > > Hmm, so one error code abuse replaced by another? > I know that ENOMEM would revert 4a6018f7 which would be unfortunate but > ENOSPC doesn't feel right as well. > File systems do map ENOSPC to SIGBUS. block_page_mkwrite_return() does that. -aneesh