Linux-mm Archive on
 help / color / Atom feed
From: Oscar Salvador <>
To: Dan Williams <>
Cc: "Aneesh Kumar K.V" <>,
	Andrew Morton <>,
	David Hildenbrand <>,
	Pavel Tatashin <>,
	Michal Hocko <>, Linux MM <>,
	Linux Kernel Mailing List <>
Subject: Re: [PATCH 2/2] mm,memory_hotplug: Fix shrink_{zone,node}_span
Date: Wed, 17 Jul 2019 09:38:58 +0200
Message-ID: <20190717073853.GA22253@linux> (raw)
In-Reply-To: <>

On Tue, Jul 16, 2019 at 07:28:54PM -0700, Dan Williams wrote:
> This makes it more clear that the problem is with the "start_pfn ==
> pfn" check relative to subsections, but it does not clarify why it
> needs to clear pfn_valid() before calling shrink_zone_span().
> Sections were not invalidated prior to shrink_zone_span() in the
> pre-subsection implementation and it seems all we need is to keep the
> same semantic. I.e. skip the range that is currently being removed:

Yes, as I said in my reply to Aneesh, that is the other way I thought
when fixing it.
The reason I went this way is because it seemed more reasonable and
natural to me that pfn_valid() would just return the next active

I just though that we could leverage the fact that we can deactivate
a sub-section before scanning for the next one.

On a second thought, the changes do not outweight the case, being the first
fix enough and less intrusive, so I will send a v2 with that instead.

Oscar Salvador

  reply index

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-15  8:15 [PATCH 0/2] Fixes for sub-section hotplug Oscar Salvador
2019-07-15  8:15 ` [PATCH 1/2] mm,sparse: Fix deactivate_section for early sections Oscar Salvador
2019-07-15 16:02   ` Aneesh Kumar K.V
2019-07-16  4:33   ` Dan Williams
2019-07-18 12:07   ` David Hildenbrand
2019-07-15  8:15 ` [PATCH 2/2] mm,memory_hotplug: Fix shrink_{zone,node}_span Oscar Salvador
2019-07-15 16:11   ` Aneesh Kumar K.V
2019-07-15 21:24     ` Oscar Salvador
2019-07-17  2:28       ` Dan Williams
2019-07-17  7:38         ` Oscar Salvador [this message]
2019-07-17  8:01           ` David Hildenbrand
2019-07-17  8:08             ` Oscar Salvador
2019-07-17  5:38       ` Aneesh Kumar K.V
2019-07-17  7:42         ` Oscar Salvador
2019-07-18 12:05   ` Oscar Salvador

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:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190717073853.GA22253@linux \ \ \ \ \ \ \ \ \ \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-mm Archive on

Archives are clonable:
	git clone --mirror linux-mm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-mm linux-mm/ \
	public-inbox-index linux-mm

Example config snippet for mirrors

Newsgroup available over NNTP:

AGPL code for this site: git clone