From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E93BECD4F21 for ; Thu, 14 May 2026 02:35:52 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5F42D6B008A; Wed, 13 May 2026 22:35:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5CACC6B008C; Wed, 13 May 2026 22:35:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 508BF6B0092; Wed, 13 May 2026 22:35:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 41A566B008A for ; Wed, 13 May 2026 22:35:52 -0400 (EDT) Received: from smtpin08.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay04.hostedemail.com (Postfix) with ESMTP id E47AA1A0221 for ; Thu, 14 May 2026 02:35:51 +0000 (UTC) X-FDA: 84764460102.08.05EEBC2 Received: from out-171.mta0.migadu.com (out-171.mta0.migadu.com [91.218.175.171]) by imf10.hostedemail.com (Postfix) with ESMTP id ED2DAC0004 for ; Thu, 14 May 2026 02:35:49 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=G+ZKSnnC; spf=pass (imf10.hostedemail.com: domain of muchun.song@linux.dev designates 91.218.175.171 as permitted sender) smtp.mailfrom=muchun.song@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1778726150; h=from:from:sender: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:dkim-signature; bh=L4R4J3RwmjA53m4R5RtoEscHz/YnvUKFxIVx8Fa4X0Y=; b=nW0TcUItA/Cge11nxpL49S15OfY/4L5urgrE2kAZheYBFM6pqjs0GWJCZpYFZxl7xaPtLe JhoLQWeN+2dp89SAZ6KorHHeuN2tZkoxAItk6zTikZDxVhGCMaO/mV2G69Gp1rlAPSwTKv PcYjWSS5Y96fmXhE35t8AAQC16liF/k= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=G+ZKSnnC; spf=pass (imf10.hostedemail.com: domain of muchun.song@linux.dev designates 91.218.175.171 as permitted sender) smtp.mailfrom=muchun.song@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1778726150; a=rsa-sha256; cv=none; b=WbaJ0b6zB39XY1KfbTCC9146B+yR/0Omr+EBww7U1C29ac84fuGAuP5Qgrji0r5qLL4+Xj lIhuyVwgBMThO39ZkuFGHw4wDti30h53x5+76dkzcESogSEmv5f8BY/NogWJJOq+FRRX2E q0ceVYrjrxjzEYQmr9IPZsk9Sw5ALtk= Content-Type: text/plain; charset=us-ascii DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1778726147; 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=L4R4J3RwmjA53m4R5RtoEscHz/YnvUKFxIVx8Fa4X0Y=; b=G+ZKSnnCixAkusAvNx6AviFC3l0Yw71F5NKxYrgFc01CFGNA8UCorUPtvcKSg93EZexN6o LY/S4mSvSVORzskYnSqY3BqBXcs53W74fBdTaaxkCqDTFWUT87NxnO7gEnFac81DF2uyN/ sbLMEsPwxcBoPKg6XFBJX2woeDspPkc= Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3864.500.181\)) Subject: Re: [PATCH v2 00/69] mm: Generalize HVO for HugeTLB and device DAX X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Muchun Song In-Reply-To: <20260513104640.b0f02b844c57f92bc954878e@linux-foundation.org> Date: Thu, 14 May 2026 10:34:56 +0800 Cc: Muchun Song , David Hildenbrand , Oscar Salvador , Michael Ellerman , Madhavan Srinivasan , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Nicholas Piggin , Christophe Leroy , Ackerley Tng , Frank van der Linden , aneesh.kumar@linux.ibm.com, joao.m.martins@oracle.com, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: <72F6690C-D94B-4398-87C7-4611A96C50AC@linux.dev> References: <20260513130542.35604-1-songmuchun@bytedance.com> <20260513104640.b0f02b844c57f92bc954878e@linux-foundation.org> To: Andrew Morton X-Migadu-Flow: FLOW_OUT X-Rspam-User: X-Rspamd-Queue-Id: ED2DAC0004 X-Rspamd-Server: rspam06 X-Stat-Signature: d39x3q5qbj5hp4g3rapzuum3no5s5eoa X-HE-Tag: 1778726149-186218 X-HE-Meta: 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 7fbYe3CE VTRUVcRsjvvashRikFEanBJvSUslucLlGSzeERFNZoeyTitLsxvz7CGlllC2FEz/HIjCI1knLcMwv2Y1LaI9xRO+wGhl+f/deP38U+u1vOC/JtCwuujSKIrKPhA1F5c/WHRDOM+nGfFiLbMZCY43ziMiQux4339v4EqeOBfmFeZc5ajMsdyVxphdMIzbb+lRAT/QRA/Sppu9kM4GUoYbIu9PQigHg+SbXIDLLLvhBwZ3HqxRO8sfZo8LdtzP9Tnc7gecUq3QQqLqHHEzvDXco2Uh/cwEAZuMhkj/02C89B3HH9K9a2vbTsX2a2+uN+IzuukV6 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > On May 14, 2026, at 01:46, Andrew Morton = wrote: >=20 > On Wed, 13 May 2026 21:04:28 +0800 Muchun Song = wrote: >=20 >> In this series, HVO is redefined as Hugepage Vmemmap Optimization: a >> general vmemmap optimization model for large hugepage-backed = mappings, >> rather than a HugeTLB-only implementation detail. >>=20 >> The existing code grew around the original HugeTLB-specific HVO path, >> while device DAX developed similar but separate vmemmap optimization >> handling. As a result, the current implementation carries duplicated >> logic, boot-time special cases, and subsystem-specific interfaces = around >> what is fundamentally the same sparse-vmemmap optimization. >>=20 >> This series generalizes that optimization into a common framework = used >> by both HugeTLB and device DAX. >>=20 >> The first few patches include some minor bug fixes found during = AI-aided >> review of the current code. These fixes are not the main goal of the >> series, but the later refactoring and unification work depends on = them, >> so they are included here as preparatory changes. >>=20 >> The series then reworks the relevant early boot and sparse >> initialization paths, introduces a generic section-based = sparse-vmemmap >> optimization infrastructure, switches HugeTLB and device DAX over to = the >> shared implementation, and removes the old special-case code. >>=20 >> ... >>=20 >> 46 files changed, 743 insertions(+), 1812 deletions(-) >=20 > Gulp. Sorry for a so big series to refactor lots of things. >=20 > I think the first 15ish patches (little fixes and cleanups and > refactorings) are ready to go in immediately? Overall, I believe the first 12 patches (excluding the bugfixes) have already been reviewed by Mike and are theoretically ready to be merged. >=20 > Perhaps you could prepare such things as a separate series. Or tell = me > which ones are suitable and I'll fudge up a [0/N]? I'd prefer to group the first 19 patches into a single series (titled "Refactor bootmem gigantic hugepage allocation"). Therefore, I suggest waiting for feedback from other maintainers/reviewers; once patches 13-19 pass review, I will send them out as a standalone series. Muchun, Thanks.