From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-186.mta0.migadu.com (out-186.mta0.migadu.com [91.218.175.186]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6C2C23F2106 for ; Mon, 20 Jul 2026 11:10:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.186 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784545858; cv=none; b=Gy1NX8XexlEJCgQu+T5PeX+Ua6RcDTWcPHWjAsPCEbyhlgjvVj7JHKebpCq0uQ+969y5AKLwvMW0zzumqD6u+xAhY47g9KOYx7kzBNwV8tDJktRteM24uIqR4IVmVKu2Gu5YudvhuAQi2gpae32sKf4WNoqVsZLB5w/qtCF8b+0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784545858; c=relaxed/simple; bh=CY3D2G8Mcf8naJ39Kb2qNt3PpH1v79jSaiicxK5PMgk=; h=Content-Type:Mime-Version:Subject:From:In-Reply-To:Date:Cc: Message-Id:References:To; b=BJKQDWBJkKHaz6by1h5jXRbO5L+Drpe5yq/Khuz8omU26+yI2xIGiKO59b9qcULEw1qHLrsTkkNDgNR70L5dcHQlleiYrNDl8M1MqL9sB57uXecqflx4UBbxFDttqHVclf+jkWXrgX1y44LoqS4X4A3594hPlBhEktAyu6LzvNo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=lgnctbmE; arc=none smtp.client-ip=91.218.175.186 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="lgnctbmE" Content-Type: text/plain; charset=us-ascii DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1784545853; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CY3D2G8Mcf8naJ39Kb2qNt3PpH1v79jSaiicxK5PMgk=; b=lgnctbmEgU7E4T16WW5A1XlyEAVa/GZA6Cp+b53JNdazm4iMZJZUiRMZNvAUGTH/ONEVGA Xt4rE6RLGfpO/JbaU+UoaMO45oe8wJc+vq4Ys5KPcCbHN0LkMAbdfwNSy10onMJFFp3GfH O9kTSia+Lxwbn90azwujpxqyDHYNvY4= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3864.600.51.1.1\)) Subject: Re: [PATCH v2 08/17] mm/sparse-vmemmap: support section-based vmemmap optimization X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Muchun Song In-Reply-To: <20260720093127.540540-9-songmuchun@bytedance.com> Date: Mon, 20 Jul 2026 19:10:23 +0800 Cc: Andrew Morton , Oscar Salvador , David Hildenbrand , Mike Rapoport , Vlastimil Babka , Lorenzo Stoakes , Michal Hocko , David Laight , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: References: <20260720093127.540540-1-songmuchun@bytedance.com> <20260720093127.540540-9-songmuchun@bytedance.com> To: Muchun Song X-Migadu-Flow: FLOW_OUT > On Jul 20, 2026, at 17:31, Muchun Song = wrote: >=20 > Teach sparse-vmemmap population code to use the compound page order > when deciding whether a vmemmap page can be optimized. >=20 > With this information, the common sparse-vmemmap population path can > allocate or reuse shared tail vmemmap pages directly instead of = relying > on HugeTLB-specific handling. >=20 > This centralizes vmemmap optimization logic in the sparse-vmemmap = code, > based on section metadata, and prepares for sharing the same mechanism > across different users of vmemmap optimization, including HugeTLB and > DAX. >=20 > Signed-off-by: Muchun Song Sashiko reported four issues [1] regarding memory hotplug, but the = entire series doesn't actually support applying HVO via memory hotplug. = Therefore, all four of these issues are false positives. [1] = https://sashiko.dev/#/patchset/20260720093127.540540-1-songmuchun%40byteda= nce.com?part=3D8=