From: Michal Hocko <mhocko@suse.com>
To: David Hildenbrand <david@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org,
"Michael S. Tsirkin" <mst@redhat.com>,
Jason Wang <jasowang@redhat.com>,
Alexey Dobriyan <adobriyan@gmail.com>,
Mike Rapoport <rppt@kernel.org>,
"Matthew Wilcox (Oracle)" <willy@infradead.org>,
Oscar Salvador <osalvador@suse.de>, Roman Gushchin <guro@fb.com>,
Alex Shi <alex.shi@linux.alibaba.com>,
Steven Price <steven.price@arm.com>,
Mike Kravetz <mike.kravetz@oracle.com>,
Aili Yao <yaoaili@kingsoft.com>, Jiri Bohac <jbohac@suse.cz>,
"K. Y. Srinivasan" <kys@microsoft.com>,
Haiyang Zhang <haiyangz@microsoft.com>,
Stephen Hemminger <sthemmin@microsoft.com>,
Wei Liu <wei.liu@kernel.org>,
Naoya Horiguchi <naoya.horiguchi@nec.com>,
linux-hyperv@vger.kernel.org,
virtualization@lists.linux-foundation.org,
linux-fsdevel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH v1 3/7] mm: rename and move page_is_poisoned()
Date: Wed, 5 May 2021 15:45:47 +0200 [thread overview]
Message-ID: <YJKhi6T33UmiZ/kE@dhcp22.suse.cz> (raw)
In-Reply-To: <57ac524c-b49a-99ec-c1e4-ef5027bfb61b@redhat.com>
On Wed 05-05-21 15:39:08, David Hildenbrand wrote:
> > > Long story short, this should be good enough for the cases we actually can
> > > handle? What am I missing?
> >
> > I am not sure I follow. My point is that I fail to see any added value
> > of the check as it doesn't prevent the race (it fundamentally cannot as
> > the page can be poisoned at any time) but the failure path doesn't
> > put_page which is incorrect even for hwpoison pages.
>
> Oh, I think you are right. If we have a page and return NULL we would leak a
> reference.
>
> Actually, we discussed in that thread handling this entirely differently,
> which resulted in a v7 [1]; however Andrew moved forward with this
> (outdated?) patch, maybe that was just a mistake?
>
> Yes, I agree we should revert that patch for now.
OK, Let me send the revert to Andrew.
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2021-05-05 13:45 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-29 12:25 [PATCH v1 0/7] fs/proc/kcore: don't read offline sections, logically offline pages and hwpoisoned pages David Hildenbrand
2021-04-29 12:25 ` [PATCH v1 1/7] fs/proc/kcore: drop KCORE_REMAP and KCORE_OTHER David Hildenbrand
2021-05-02 6:31 ` Mike Rapoport
2021-04-29 12:25 ` [PATCH v1 2/7] fs/proc/kcore: pfn_is_ram check only applies to KCORE_RAM David Hildenbrand
2021-05-02 6:31 ` Mike Rapoport
2021-04-29 12:25 ` [PATCH v1 3/7] mm: rename and move page_is_poisoned() David Hildenbrand
2021-05-02 6:32 ` Mike Rapoport
2021-05-05 13:13 ` Michal Hocko
2021-05-05 13:17 ` David Hildenbrand
2021-05-05 13:27 ` Michal Hocko
2021-05-05 13:39 ` David Hildenbrand
2021-05-05 13:45 ` Michal Hocko [this message]
2021-05-06 1:08 ` Aili Yao
2021-05-06 0:56 ` Aili Yao
2021-05-06 7:06 ` Michal Hocko
2021-05-06 7:28 ` Aili Yao
2021-05-06 7:55 ` Michal Hocko
2021-05-06 8:52 ` Aili Yao
2021-04-29 12:25 ` [PATCH v1 4/7] fs/proc/kcore: don't read offline sections, logically offline pages and hwpoisoned pages David Hildenbrand
2021-05-02 6:32 ` Mike Rapoport
2021-04-29 12:25 ` [PATCH v1 5/7] mm: introduce page_offline_(begin|end|freeze|unfreeze) to synchronize setting PageOffline() David Hildenbrand
2021-05-02 6:33 ` Mike Rapoport
2021-05-03 8:11 ` David Hildenbrand
2021-05-05 13:24 ` Michal Hocko
2021-05-05 15:10 ` David Hildenbrand
2021-05-05 17:41 ` Mike Rapoport
2021-04-29 12:25 ` [PATCH v1 6/7] virtio-mem: use page_offline_(start|end) when " David Hildenbrand
2021-05-02 6:33 ` Mike Rapoport
2021-05-03 8:16 ` David Hildenbrand
2021-05-03 8:23 ` Michael S. Tsirkin
2021-04-29 12:25 ` [PATCH v1 7/7] fs/proc/kcore: use page_offline_(freeze|unfreeze) David Hildenbrand
2021-05-02 6:34 ` Mike Rapoport
2021-05-03 8:28 ` David Hildenbrand
2021-05-03 9:28 ` Mike Rapoport
2021-05-03 10:13 ` David Hildenbrand
2021-05-03 11:33 ` Mike Rapoport
2021-05-03 11:35 ` David Hildenbrand
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=YJKhi6T33UmiZ/kE@dhcp22.suse.cz \
--to=mhocko@suse.com \
--cc=adobriyan@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=alex.shi@linux.alibaba.com \
--cc=david@redhat.com \
--cc=guro@fb.com \
--cc=haiyangz@microsoft.com \
--cc=jasowang@redhat.com \
--cc=jbohac@suse.cz \
--cc=kys@microsoft.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-hyperv@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mike.kravetz@oracle.com \
--cc=mst@redhat.com \
--cc=naoya.horiguchi@nec.com \
--cc=osalvador@suse.de \
--cc=rppt@kernel.org \
--cc=steven.price@arm.com \
--cc=sthemmin@microsoft.com \
--cc=virtualization@lists.linux-foundation.org \
--cc=wei.liu@kernel.org \
--cc=willy@infradead.org \
--cc=yaoaili@kingsoft.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).