From: Mike Kravetz <mike.kravetz@oracle.com>
To: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
Andrew Morton <akpm@linux-foundation.org>
Cc: "linux-mm@kvack.org" <linux-mm@kvack.org>,
Michal Hocko <mhocko@kernel.org>,
"xishi.qiuxishi@alibaba-inc.com" <xishi.qiuxishi@alibaba-inc.com>,
"zy.zhengyi@alibaba-inc.com" <zy.zhengyi@alibaba-inc.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 0/2] mm: soft-offline: fix race against page allocation
Date: Tue, 21 Aug 2018 19:25:12 -0700 [thread overview]
Message-ID: <c692fd0b-d282-f2e7-b42f-b3204ad35938@oracle.com> (raw)
In-Reply-To: <20180822013748.GA10343@hori1.linux.bs1.fc.nec.co.jp>
On 08/21/2018 06:37 PM, Naoya Horiguchi wrote:
> On Wed, Aug 15, 2018 at 03:43:34PM -0700, Andrew Morton wrote:
>> On Tue, 17 Jul 2018 14:32:30 +0900 Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> wrote:
>>
>>> I've updated the patchset based on feedbacks:
>>>
>>> - updated comments (from Andrew),
>>> - moved calling set_hwpoison_free_buddy_page() from mm/migrate.c to mm/memory-failure.c,
>>> which is necessary to check the return code of set_hwpoison_free_buddy_page(),
>>> - lkp bot reported a build error when only 1/2 is applied.
>>>
>>> > mm/memory-failure.c: In function 'soft_offline_huge_page':
>>> > >> mm/memory-failure.c:1610:8: error: implicit declaration of function
>>> > 'set_hwpoison_free_buddy_page'; did you mean 'is_free_buddy_page'?
>>> > [-Werror=implicit-function-declaration]
>>> > if (set_hwpoison_free_buddy_page(page))
>>> > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>> > is_free_buddy_page
>>> > cc1: some warnings being treated as errors
>>>
>>> set_hwpoison_free_buddy_page() is defined in 2/2, so we can't use it
>>> in 1/2. Simply doing s/set_hwpoison_free_buddy_page/!TestSetPageHWPoison/
>>> will fix this.
>>>
>>> v1: https://lkml.org/lkml/2018/7/12/968
>>>
>>
>> Quite a bit of discussion on these two, but no actual acks or
>> review-by's?
>
> Really sorry for late response.
> Xishi provided feedback on previous version, but no final ack/reviewed-by.
> This fix should work on the reported issue, but rewriting soft-offlining
> without PageHWPoison flag would be the better fix (no actual patch yet.)
> I'm not sure this patch should go to mainline immediately.
FWIW - The 'migration of huge PMD shared pages' issue I am working was
originally triggered via soft-offline. While working the issue, I tried
to exercise huge page soft-offline really hard to recreate the issue and
validate a fix. However, I was more likely to hit the soft-offline race(s)
your patches address. Therefore, I applied your patches to focus my testing
and validation on the migration of huge PMD shared pages issue. That is sort
of a Tested-by :).
Just wanted to point out that it was pretty easy to hit this issue. It
was easier than the issue I am working. And, the issue I am trying to
address was seen in a real customer environment. So, I would not be
surprised to see this issue in real customer environments as well.
If you (or others) think we should go forward with these patches, I can
spend some time doing a review. Already did a 'quick look' some time back.
--
Mike Kravetz
next prev parent reply other threads:[~2018-08-22 2:25 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-17 5:32 [PATCH v2 0/2] mm: soft-offline: fix race against page allocation Naoya Horiguchi
2018-07-17 5:32 ` [PATCH v2 1/2] mm: fix race on soft-offlining free huge pages Naoya Horiguchi
2018-07-17 14:27 ` Michal Hocko
2018-07-17 20:10 ` Mike Kravetz
2018-07-18 1:28 ` Naoya Horiguchi
2018-07-18 2:36 ` Mike Kravetz
2018-07-18 0:55 ` Naoya Horiguchi
2018-07-18 1:41 ` Naoya Horiguchi
2018-07-18 8:50 ` Michal Hocko
2018-07-19 6:19 ` Naoya Horiguchi
2018-07-19 7:15 ` Michal Hocko
2018-07-19 8:08 ` Naoya Horiguchi
2018-07-19 8:27 ` Michal Hocko
2018-07-19 9:22 ` Naoya Horiguchi
2018-07-19 10:32 ` Michal Hocko
2018-07-17 5:32 ` [PATCH v2 2/2] mm: soft-offline: close the race against page allocation Naoya Horiguchi
2018-08-15 22:43 ` [PATCH v2 0/2] mm: soft-offline: fix " Andrew Morton
2018-08-22 1:37 ` Naoya Horiguchi
2018-08-22 2:25 ` Mike Kravetz [this message]
2018-08-22 8:00 ` Michal Hocko
2018-10-26 8:46 ` Michal Hocko
2018-10-30 6:54 ` Naoya Horiguchi
2018-10-30 8:16 ` Michal Hocko
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=c692fd0b-d282-f2e7-b42f-b3204ad35938@oracle.com \
--to=mike.kravetz@oracle.com \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mhocko@kernel.org \
--cc=n-horiguchi@ah.jp.nec.com \
--cc=xishi.qiuxishi@alibaba-inc.com \
--cc=zy.zhengyi@alibaba-inc.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).