From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 9B77D3C76AD for ; Thu, 1 Oct 2026 07:48:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790840932; cv=none; b=Fe9oMJGKJZpQ3D43LplX8oiJ0OFqE+qzm5JObCSBPfgnyZw/c2rsqZBjAmVlhpQakshHEFVD16oNmBWUlRTible9v2+jqIYmI76LFHh/p+lveH8b72CcUlGQuhQOwVolamGcQ718edQPSsDpdn1IsbsSqPcdxLfgBZOBPJ3h1eg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790840932; c=relaxed/simple; bh=nr+7QF36vSIUflaxoTuPuB0Fun8v2A6FN6t9an3H6dk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ian+i9UvlcmUeneXo5377cK58oMeShYhr0Ia+oj6cLD6GZPdxZAdssRmHYnFxklOtpYonNYFPKVHyd+pYiMLFGNU6rQzpNDQY4RaJblkOwexIc14CR3dJpmbOmXBrDlF38sCZJq7ANjS8vHxhry/6W9PbtvkbkriCW0eJhz1+SM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Qygm2R6W; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Qygm2R6W" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 579AE1F000FF; Thu, 1 Oct 2026 07:48:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790840931; bh=mNjIuXpUThvFyotQd9GSbJFtJ0698ZsWlEkeLqDq+J0=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=Qygm2R6WcC4oKwDn9p3fd5ZxtzzH5bVE56ZCY4ydjNT+BVGfjf1B1VfA/6LcKKxnD fgLc2Ii0Qk1vYBGKiMS96qmJDfepfm6PRk1ZHAR4tc4j3LGDTnbxZaiq+YJwFjnIfr n/a2pBckpty8tFctrBoQ/Wnzfguno5IwnqdBOVPBx3SAgqgtUnlpSpuzYvsB7o6jDn Ntw53BUZ5DWbC9EVG9R+a6qMFrI01y74S36eh+kibIoXFmN+T/24B694H2MQVfF2Z3 MOHLkbN/ggiH6IuMJqfIYSI7Q9jpQk5kCHodR/m/MUMeXjbsLR+4k9bgqAu8r5KZ55 fxTrgkQDj6igw== Message-ID: <964df3e4-b9a4-4741-b8dc-cb8ef02adeec@kernel.org> Date: Thu, 1 Oct 2026 09:48:44 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 0/6] mm: swap support for hugetlb folios To: Zongkun Lei Cc: linux-mm@kvack.org, Andrew Morton , Muchun Song , Oscar Salvador , Peter Xu , Matthew Wilcox , Kairui Song , Michal Hocko , Johannes Weiner , Hugh Dickins , Naoya Horiguchi , Zi Yan , Lorenzo Stoakes , linux-kernel@vger.kernel.org References: From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/29/26 11:26, Zongkun Lei wrote: > On Tue, 29 Sep 2026 10:02:11 +0200, David Hildenbrand wrote: >> Hugetlb is effectively in a feature freeze. There is no interest in >> maintaining even more of the special hugetlb sauce, sorry. :/ > > Understood -- thank you for the direct answer. > > My mistake was misreading the subsystem's direction. I had read the > earlier list discussions and concluded that the red line was touching > hugetlb's reservation semantics, so I designed the whole series to > keep them intact -- user-driven only, no LRU, no reclaim hooks. I > see now that the actual position is a feature freeze: not "new > features are welcome if reservations stay sacred", but no new > features at all. > > Going forward I will stick to work that reduces hugetlb's divergence > from generic code rather than adding to it, and I will float ideas > on the list before putting serious effort into anything big. Yes, that's usually the best approach: if you intend to do a rather invasive and/or likely controversial work, better reach out to the community+maintainers early. Most of us prefer a well written problem statement + high-level design idea, as it rather focuses on requirements + exploring solution space vs. a concrete solution. -- Cheers, David