From: Toshiki Fukasawa <t-fukasawa@vx.jp.nec.com>
To: Waiman Long <longman@redhat.com>, Michal Hocko <mhocko@kernel.org>
Cc: Dan Williams <dan.j.williams@gmail.com>,
Alexey Dobriyan <adobriyan@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
Stephen Rothwell <sfr@canb.auug.org.au>,
"Michael S. Tsirkin" <mst@redhat.com>,
Junichi Nomura <j-nomura@ce.jp.nec.com>,
Toshiki Fukasawa <t-fukasawa@vx.jp.nec.com>
Subject: Re: [PATCH v2] fs/proc/page: Skip uninitialized page when iterating page structures
Date: Thu, 29 Aug 2019 01:47:13 +0000 [thread overview]
Message-ID: <9a1395bc-d568-c4d7-2dde-7dde7b48ac0b@vx.jp.nec.com> (raw)
In-Reply-To: <4367f507-97ba-a74e-6bf5-811cdd6ecdf9@redhat.com>
On 2019/08/28 23:18, Waiman Long wrote:
> On 8/28/19 10:09 AM, Michal Hocko wrote:
>> On Wed 28-08-19 09:46:21, Waiman Long wrote:
>>> On 8/28/19 4:00 AM, Michal Hocko wrote:
>>>> On Tue 27-08-19 16:22:38, Michal Hocko wrote:
>>>>> Dan, isn't this something we have discussed recently?
>>>> This was http://lkml.kernel.org/r/20190725023100.31141-3-t-fukasawa@vx.jp.nec.com
>>>> and talked about /proc/kpageflags but this is essentially the same thing
>>>> AFAIU. I hope we get a consistent solution for both issues.
>>>>
>>> Yes, it is the same problem. The uninitialized page structure problem
>>> affects all the 3 /proc/kpage{cgroup,count,flags) files.
>>>
>>> Toshiki's patch seems to fix it just for /proc/kpageflags, though.
>> Yup. I was arguing that whacking a mole kinda fix is far from good. Dan
>> had some arguments on why initializing those struct pages is a problem.
>> The discussion had a half open end though. I hoped that Dan would try
>> out the initialization side but I migh have misunderstood.
>
> If the page structures of the reserved PFNs are always initialized, that
> will fix the problem too. I am not familiar with the zone device code.
> So I didn't attempt to do that.
>
> Cheers,
> Longman
>
>
I also think that the struct pages should be initialized.
I'm preparing to post the patch.
Toshiki Fukasawa
prev parent reply other threads:[~2019-08-29 3:39 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-26 12:43 [PATCH v2] fs/proc/page: Skip uninitialized page when iterating page structures Waiman Long
2019-08-26 13:25 ` Matthew Wilcox
2019-08-26 13:43 ` Waiman Long
2019-08-26 13:49 ` Waiman Long
2019-08-26 14:20 ` Matthew Wilcox
2019-08-27 14:22 ` Michal Hocko
2019-08-28 8:00 ` Michal Hocko
2019-08-28 13:46 ` Waiman Long
2019-08-28 14:09 ` Michal Hocko
2019-08-28 14:18 ` Waiman Long
2019-08-29 1:47 ` Toshiki Fukasawa [this message]
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