From: Muchun Song <muchun.song@linux.dev>
To: Kaitao Cheng <kaitao.cheng@linux.dev>
Cc: Andy Lutomirski <luto@kernel.org>,
Thomas Gleixner <tglx@kernel.org>, Ingo Molnar <mingo@redhat.com>,
Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
x86@kernel.org, "H . Peter Anvin" <hpa@zytor.com>,
Andrew Morton <akpm@linux-foundation.org>,
David Hildenbrand <david@kernel.org>,
Lorenzo Stoakes <ljs@kernel.org>,
"Liam R . Howlett" <liam@infradead.org>,
Vlastimil Babka <vbabka@kernel.org>,
Mike Rapoport <rppt@kernel.org>,
Suren Baghdasaryan <surenb@google.com>,
Michal Hocko <mhocko@suse.com>, Kairui Song <kasong@tencent.com>,
Qi Zheng <qi.zheng@linux.dev>,
Shakeel Butt <shakeel.butt@linux.dev>,
Barry Song <baohua@kernel.org>,
Axel Rasmussen <axelrasmussen@google.com>,
Yuanchu Xie <yuanchu@google.com>, Wei Xu <weixugc@google.com>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
Kaitao Cheng <chengkaitao@kylinos.cn>
Subject: Re: [PATCH] mm: Add CONFIG_SPARSEMEM_CLASSIC
Date: Sun, 20 Sep 2026 17:59:22 +0800 [thread overview]
Message-ID: <85F48B20-68C5-45D7-A8E7-27E601283743@linux.dev> (raw)
In-Reply-To: <20260920070406.95354-1-kaitao.cheng@linux.dev>
> On Sep 20, 2026, at 15:04, Kaitao Cheng <kaitao.cheng@linux.dev> wrote:
>
> From: Kaitao Cheng <chengkaitao@kylinos.cn>
>
> Several MM paths identify classic sparse memory by testing
> CONFIG_SPARSEMEM while also testing that CONFIG_SPARSEMEM_VMEMMAP is
> disabled. Repeating the compound condition obscures the memory model being
> selected and requires the local SECTION_IN_PAGE_FLAGS alias for the same
> state.
>
> Add CONFIG_SPARSEMEM_CLASSIC as a hidden derived option and use it at the
> conditional sites. Remove SECTION_IN_PAGE_FLAGS and test the new option
> directly.
>
> The x86 32-bit vDSO build starts with the x86_64 configuration and then
> undefines CONFIG_SPARSEMEM_VMEMMAP to emulate a 32-bit configuration.
> Kconfig-derived symbols are not recomputed by the C preprocessor, so define
> CONFIG_SPARSEMEM_CLASSIC there when CONFIG_SPARSEMEM is enabled. This
> preserves the existing behavior.
>
> Signed-off-by: Kaitao Cheng <chengkaitao@kylinos.cn>
Acked-by: Muchun Song <muchun.song@linux.dev>
Thanks.
next prev parent reply other threads:[~2026-09-20 9:59 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-20 7:04 Kaitao Cheng
2026-09-20 9:59 ` Muchun Song [this message]
2026-09-21 10:34 ` David Hildenbrand (Arm)
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=85F48B20-68C5-45D7-A8E7-27E601283743@linux.dev \
--to=muchun.song@linux.dev \
--cc=akpm@linux-foundation.org \
--cc=axelrasmussen@google.com \
--cc=baohua@kernel.org \
--cc=bp@alien8.de \
--cc=chengkaitao@kylinos.cn \
--cc=dave.hansen@linux.intel.com \
--cc=david@kernel.org \
--cc=hpa@zytor.com \
--cc=kaitao.cheng@linux.dev \
--cc=kasong@tencent.com \
--cc=liam@infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=ljs@kernel.org \
--cc=luto@kernel.org \
--cc=mhocko@suse.com \
--cc=mingo@redhat.com \
--cc=qi.zheng@linux.dev \
--cc=rppt@kernel.org \
--cc=shakeel.butt@linux.dev \
--cc=surenb@google.com \
--cc=tglx@kernel.org \
--cc=vbabka@kernel.org \
--cc=weixugc@google.com \
--cc=x86@kernel.org \
--cc=yuanchu@google.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
all inboxes | Powered by JetHome®