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 9E530CD37AC for ; Wed, 13 May 2026 18:27:02 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 8BE976B009B; Wed, 13 May 2026 14:27:01 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 896586B009D; Wed, 13 May 2026 14:27:01 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7ABFE6B009E; Wed, 13 May 2026 14:27:01 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 69B446B009B for ; Wed, 13 May 2026 14:27:01 -0400 (EDT) Received: from smtpin16.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 1B0891A020B for ; Wed, 13 May 2026 18:27:01 +0000 (UTC) X-FDA: 84763228242.16.C2A9994 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.223.131]) by imf06.hostedemail.com (Postfix) with ESMTP id C7D4E18000F for ; Wed, 13 May 2026 18:26:58 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=FhMJJ1Xk; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=UWfRRZTE; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=FhMJJ1Xk; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=UWfRRZTE; spf=pass (imf06.hostedemail.com: domain of osalvador@suse.de designates 195.135.223.131 as permitted sender) smtp.mailfrom=osalvador@suse.de; dmarc=pass (policy=none) header.from=suse.de ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1778696819; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=CMY3vjl7HirudEIlBL9RQXThipPsv2YSmm9hm08krqM=; b=jmjF/gnGn4eMsmtUP05yOwmGxu5jgWJghSroLRtAgkGE9m0KDSDVytTyadcoxmAdUri0/b 2HRHXfZOWJ/4d9HGIaZz161Gp1NjJTXH8HW8qqWUoy5S3TjD6I2EfX85U2kV39Dw5DnMXB +CeEn17FK69FpJLFitfoX/ihbPt9aLg= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=FhMJJ1Xk; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=UWfRRZTE; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=FhMJJ1Xk; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=UWfRRZTE; spf=pass (imf06.hostedemail.com: domain of osalvador@suse.de designates 195.135.223.131 as permitted sender) smtp.mailfrom=osalvador@suse.de; dmarc=pass (policy=none) header.from=suse.de ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1778696819; a=rsa-sha256; cv=none; b=EhRTUvusc0JOpfoWpUilSPDEENkDpPMMl+xUKxetjGWnRcM8qhJQBeQhS5pLkeKClF2F3g ODYLjruV6qdLpeWk2pzUF8tIzfcBl1dAAsHI3yqQn69eYXS0/ZeTlIX8Wuxct8mhSN0Kqg jOxQdHa/HSJPSiwwuR4kZ2UAKyrjjsI= Received: from imap1.dmz-prg2.suse.org (unknown [10.150.64.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 2A4E1685BE; Wed, 13 May 2026 18:26:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1778696817; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=CMY3vjl7HirudEIlBL9RQXThipPsv2YSmm9hm08krqM=; b=FhMJJ1Xk2ZqhzR8+BOHNu26g3TctsKnhgOuylmu2zcMuQ9ewQgmJSWlsfYsCiplTR3qmed 8HXR8BmdcN2BnUs04wQUFnkyXxeh27JKHAbSnHLYxMXAxJs/KT6r4t4eqlGtp/DeAf+1OB d610aUqO/vVb7CB2bXQFdREMX9YB43U= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1778696817; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=CMY3vjl7HirudEIlBL9RQXThipPsv2YSmm9hm08krqM=; b=UWfRRZTEAe5DK2MG9+vW7LYL4ie/9230tpzuWeR8U+Se0O0iSLkfpegh/KmTfRzPRONU27 sCnPCB7pFBrJLHAw== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1778696817; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=CMY3vjl7HirudEIlBL9RQXThipPsv2YSmm9hm08krqM=; b=FhMJJ1Xk2ZqhzR8+BOHNu26g3TctsKnhgOuylmu2zcMuQ9ewQgmJSWlsfYsCiplTR3qmed 8HXR8BmdcN2BnUs04wQUFnkyXxeh27JKHAbSnHLYxMXAxJs/KT6r4t4eqlGtp/DeAf+1OB d610aUqO/vVb7CB2bXQFdREMX9YB43U= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1778696817; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=CMY3vjl7HirudEIlBL9RQXThipPsv2YSmm9hm08krqM=; b=UWfRRZTEAe5DK2MG9+vW7LYL4ie/9230tpzuWeR8U+Se0O0iSLkfpegh/KmTfRzPRONU27 sCnPCB7pFBrJLHAw== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 4A108593A9; Wed, 13 May 2026 18:26:56 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id WgTxD3DCBGqKCAAAD6G6ig (envelope-from ); Wed, 13 May 2026 18:26:56 +0000 Date: Wed, 13 May 2026 20:26:54 +0200 From: Oscar Salvador To: Andrew Morton Cc: Muchun Song , David Hildenbrand , Muchun Song , 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 Subject: Re: [PATCH v2 00/69] mm: Generalize HVO for HugeTLB and device DAX Message-ID: References: <20260513130542.35604-1-songmuchun@bytedance.com> <20260513104640.b0f02b844c57f92bc954878e@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260513104640.b0f02b844c57f92bc954878e@linux-foundation.org> X-Stat-Signature: zf7obmwcb45581ykwtf6yyygynzy5mp7 X-Rspamd-Queue-Id: C7D4E18000F X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1778696818-625922 X-HE-Meta: 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 dgVohX7p YMJ+MeEpSfLbsimINPtCuM3VgmHIbT5EjjQV5cuU/JQEQE74QORWERVt/ybANF5g0s6AGfRmJj050w8qGXZU8nQEMCGFjGqh+Gvyw8K8wDSDGJnZzNZqY/QE0988Y88Nzm6tltI/JRRT35/HwGo55u5cOWSJeEtclO6N6GzIeErVd2FizRLuS6HQLcPbWNatSl3b1A21IN9tdoGar9Gy7oUq8LqN4Q9Tk6lkOGlxWPATAFc6jq156k3U2/Ij0+aN7hb3KkRC4kGhTFmu6dPUfeysKA60jvqugXwJy Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, May 13, 2026 at 10:46:40AM -0700, Andrew Morton wrote: > On Wed, 13 May 2026 21:04:28 +0800 Muchun Song wrote: > > > 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. > > > > 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. > > > > This series generalizes that optimization into a common framework used > > by both HugeTLB and device DAX. > > > > 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. > > > > 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. > > > > ... > > > > 46 files changed, 743 insertions(+), 1812 deletions(-) > > Gulp. > > I think the first 15ish patches (little fixes and cleanups and > refactorings) are ready to go in immediately? I plan to have a (partial ) look at this tomorrow/Friday, but splitting this series in fixes-that-can-go-straight-away and the feature itself would make more sense and help ease the review. Head tends to spin a bit when the patchset grows beyond certain number of patches :-D. Would that be possible Munchun? -- Oscar Salvador SUSE Labs