linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Mike Rapoport <rppt@kernel.org>
To: Yajun Deng <yajun.deng@linux.dev>
Cc: David Hildenbrand <david@redhat.com>,
	akpm@linux-foundation.org, mike.kravetz@oracle.com,
	muchun.song@linux.dev, willy@infradead.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4 2/2] mm: Init page count in reserve_bootmem_region when MEMINIT_EARLY
Date: Thu, 12 Oct 2023 12:19:06 +0300	[thread overview]
Message-ID: <20231012091906.GQ3303@kernel.org> (raw)
In-Reply-To: <6545ac4c-1205-6c09-49ea-e00c24d1a2ff@linux.dev>

On Thu, Oct 05, 2023 at 10:04:28PM +0800, Yajun Deng wrote:
> 
> > > > > > > That 'if' breaks the invariant that __free_pages_core is
> > > > > > > always called for pages with initialized page count. Adding
> > > > > > > it may lead to subtle bugs and random memory corruption so we
> > > > > > > don't want to add it at the first place.
> > > > > >
> > > > > > As long as we have to special-case memory hotplug, we know that
> > > > > > we are always coming via generic_online_page() in that case. We
> > > > > > could either move some logic over there, or let
> > > > > > __free_pages_core() know what it should do.
> > > > >
> > > > > Looks like the patch rather special cases MEMINIT_EARLY, although
> > > > > I didn't check throughfully other code paths.  Anyway, relying on
> > > > > page_count() to be correct in different ways for different
> > > > > callers of __free_pages_core() does not sound right to me.
> > > >
> > > > Absolutely agreed.
> > > > 
> > > I already sent v5  a few days ago. Comments, please...
> >
> > Does it address all the feedback from this thread?
> 
> Except hotplug. 

Please reread carefully the last comments from me and from David above.

-- 
Sincerely yours,
Mike.


  reply	other threads:[~2023-10-12  9:20 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-28  8:33 [PATCH v4 0/2] mm: Don't set and reset page count in MEMINIT_EARLY Yajun Deng
2023-09-28  8:33 ` [PATCH v4 1/2] mm: pass page count and reserved to __init_single_page Yajun Deng
2023-09-29  8:19   ` Mike Rapoport
2023-09-29  9:37     ` Yajun Deng
2023-09-28  8:33 ` [PATCH v4 2/2] mm: Init page count in reserve_bootmem_region when MEMINIT_EARLY Yajun Deng
2023-09-29  8:30   ` Mike Rapoport
2023-09-29  9:50     ` Yajun Deng
2023-09-29 10:02       ` Mike Rapoport
2023-09-29 10:27         ` Yajun Deng
2023-10-01 18:59           ` Mike Rapoport
2023-10-02  7:03             ` Yajun Deng
2023-10-02  8:47               ` Mike Rapoport
2023-10-02  8:56                 ` David Hildenbrand
2023-10-02 11:10                   ` Mike Rapoport
2023-10-02 11:25                     ` David Hildenbrand
2023-10-03 14:38                       ` Yajun Deng
2023-10-05  5:06                         ` Mike Rapoport
2023-10-05 14:04                           ` Yajun Deng
2023-10-12  9:19                             ` Mike Rapoport [this message]
2023-10-12  9:36                               ` Yajun Deng
2023-10-02  8:30     ` David Hildenbrand
2023-10-08  8:57       ` Yajun Deng
2023-10-10  2:31         ` Yajun Deng
2023-10-12  9:23           ` David Hildenbrand
2023-10-12  9:53             ` Yajun Deng
2023-10-13  8:48               ` Mike Rapoport
2023-10-13  9:29                 ` Yajun Deng
2023-10-16  6:33                   ` Mike Rapoport
2023-10-16  8:10                     ` Yajun Deng
2023-10-16  8:16                       ` David Hildenbrand
2023-10-16  8:32                         ` Yajun Deng
2023-10-16  8:36                           ` David Hildenbrand
2023-10-16 10:17                             ` Yajun Deng
2023-10-17  9:58                               ` Yajun Deng

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=20231012091906.GQ3303@kernel.org \
    --to=rppt@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=david@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mike.kravetz@oracle.com \
    --cc=muchun.song@linux.dev \
    --cc=willy@infradead.org \
    --cc=yajun.deng@linux.dev \
    /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