From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlastimil Babka Subject: Re: [PATCH v1] mm/madvise: pass return code of memory_failure() to userspace Date: Wed, 27 Jan 2016 14:59:11 +0100 Message-ID: <56A8CD2F.5080903@suse.cz> References: <1453451277-20979-1-git-send-email-n-horiguchi@ah.jp.nec.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-2 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1453451277-20979-1-git-send-email-n-horiguchi-PaJj6Psr51x8UrSeD/g0lQ@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Naoya Horiguchi , Andrew Morton Cc: Chen Gong , linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Naoya Horiguchi , Linux API , linux-man-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Michael Kerrisk List-Id: linux-man@vger.kernel.org [CC += linux-api, linux-man] On 01/22/2016 09:27 AM, Naoya Horiguchi wrote: > Currently the return value of memory_failure() is not passed to userspace, which > is inconvenient for test programs that want to know the result of error handling. > So let's return it to the caller as we already do in MADV_SOFT_OFFLINE case. > > Signed-off-by: Naoya Horiguchi > --- > mm/madvise.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git v4.4-mmotm-2016-01-20-16-10/mm/madvise.c v4.4-mmotm-2016-01-20-16-10_patched/mm/madvise.c > index f56825b..6a77114 100644 > --- v4.4-mmotm-2016-01-20-16-10/mm/madvise.c > +++ v4.4-mmotm-2016-01-20-16-10_patched/mm/madvise.c > @@ -555,8 +555,9 @@ static int madvise_hwpoison(int bhv, unsigned long start, unsigned long end) > } > pr_info("Injecting memory failure for page %#lx at %#lx\n", > page_to_pfn(p), start); > - /* Ignore return value for now */ > - memory_failure(page_to_pfn(p), 0, MF_COUNT_INCREASED); > + ret = memory_failure(page_to_pfn(p), 0, MF_COUNT_INCREASED); > + if (ret) > + return ret; Can you explain what madvise can newly return for MADV_HWPOISON in which situations, for the purposes of updated man page? Thanks, Vlastimil > } > return 0; > } >