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{ "id": 2223477, "url": "http://patchwork.ozlabs.org/api/1.2/covers/2223477/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linuxppc-dev/cover/20260415111412.1003526-1-songmuchun@bytedance.com/", "project": { "id": 2, "url": "http://patchwork.ozlabs.org/api/1.2/projects/2/?format=api", "name": "Linux PPC development", "link_name": "linuxppc-dev", "list_id": "linuxppc-dev.lists.ozlabs.org", "list_email": "linuxppc-dev@lists.ozlabs.org", "web_url": "https://github.com/linuxppc/wiki/wiki", "scm_url": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git", "webscm_url": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/", "list_archive_url": "https://lore.kernel.org/linuxppc-dev/", "list_archive_url_format": "https://lore.kernel.org/linuxppc-dev/{}/", "commit_url_format": "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id={}" }, "msgid": "<20260415111412.1003526-1-songmuchun@bytedance.com>", "list_archive_url": "https://lore.kernel.org/linuxppc-dev/20260415111412.1003526-1-songmuchun@bytedance.com/", "date": "2026-04-15T11:14:06", "name": "[v2,0/6] mm: Fix vmemmap optimization accounting and initialization", "submitter": { "id": 78930, "url": "http://patchwork.ozlabs.org/api/1.2/people/78930/?format=api", "name": "Muchun Song", "email": "songmuchun@bytedance.com" }, "mbox": "http://patchwork.ozlabs.org/project/linuxppc-dev/cover/20260415111412.1003526-1-songmuchun@bytedance.com/mbox/", "series": [ { "id": 499970, "url": "http://patchwork.ozlabs.org/api/1.2/series/499970/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=499970", "date": "2026-04-15T11:14:06", "name": "mm: Fix vmemmap optimization accounting and initialization", "version": 2, "mbox": "http://patchwork.ozlabs.org/series/499970/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/covers/2223477/comments/", "headers": { "Return-Path": "\n <linuxppc-dev+bounces-19763-incoming=patchwork.ozlabs.org@lists.ozlabs.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "linuxppc-dev@lists.ozlabs.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=bytedance.com header.i=@bytedance.com\n header.a=rsa-sha256 header.s=google header.b=Rvlt1HxE;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org\n (client-ip=112.213.38.117; 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Howlett\" <Liam.Howlett@oracle.com>,\n\tVlastimil Babka <vbabka@kernel.org>,\n\tMike Rapoport <rppt@kernel.org>,\n\tSuren Baghdasaryan <surenb@google.com>,\n\tMichal Hocko <mhocko@suse.com>,\n\tNicholas Piggin <npiggin@gmail.com>,\n\tChristophe Leroy <chleroy@kernel.org>,\n\taneesh.kumar@linux.ibm.com,\n\tjoao.m.martins@oracle.com,\n\tlinux-mm@kvack.org,\n\tlinuxppc-dev@lists.ozlabs.org,\n\tlinux-kernel@vger.kernel.org,\n\tMuchun Song <songmuchun@bytedance.com>", "Subject": "[PATCH v2 0/6] mm: Fix vmemmap optimization accounting and\n initialization", "Date": "Wed, 15 Apr 2026 19:14:06 +0800", "Message-Id": "<20260415111412.1003526-1-songmuchun@bytedance.com>", "X-Mailer": "git-send-email 2.20.1", "X-Mailing-List": "linuxppc-dev@lists.ozlabs.org", "List-Id": "<linuxppc-dev.lists.ozlabs.org>", "List-Help": "<mailto:linuxppc-dev+help@lists.ozlabs.org>", "List-Owner": "<mailto:linuxppc-dev+owner@lists.ozlabs.org>", "List-Post": "<mailto:linuxppc-dev@lists.ozlabs.org>", "List-Archive": "<https://lore.kernel.org/linuxppc-dev/>,\n <https://lists.ozlabs.org/pipermail/linuxppc-dev/>", "List-Subscribe": "<mailto:linuxppc-dev+subscribe@lists.ozlabs.org>,\n <mailto:linuxppc-dev+subscribe-digest@lists.ozlabs.org>,\n <mailto:linuxppc-dev+subscribe-nomail@lists.ozlabs.org>", "List-Unsubscribe": "<mailto:linuxppc-dev+unsubscribe@lists.ozlabs.org>", "Precedence": "list", "MIME-Version": "1.0", "Content-Transfer-Encoding": "8bit", "X-Spam-Status": "No, score=-0.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID,\n\tDKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS\n\tautolearn=disabled version=4.0.1 OzLabs 8", "X-Spam-Checker-Version": "SpamAssassin 4.0.1 (2024-03-25) on lists.ozlabs.org" }, "content": "This patch series fixes a number of issues related to vmemmap optimization\nfor compound pages (e.g., DAX), including incorrect page accounting and\nmissing architecture-specific initialization steps.\n\nThe series addresses these issues through the following steps:\n- Patch 1: Fixes a vmemmap accounting underflow in error paths.\n- Patch 2-3: Fixes DAX vmemmap accounting by plumbing the pgmap\n argument through memory deactivation paths.\n- Patch 4-5: Fixes missing architecture-specific page table syncs by\n plumbing the pgmap argument through vmemmap_populate APIs.\n- Patch 6: Fixes pageblock migratetype initialization for large\n compound ZONE_DEVICE pages.\n\nChangelog:\nv1 -> v2:\n- Moved vmemmap accounting to populate_section_memmap() /\n depopulate_section_memmap() to fix accounting underflow,\n suggested by Mike.\n- Replaced VM_BUG_ON with VM_WARN_ON_ONCE as requested by David.\n- Reduced frequency of calling cond_resched() in pageblock_migratetype_init_range()\n based on feedback from David and Mike.\n- Extracted all bugfix patches from a larger patchset\n (https://lore.kernel.org/linux-mm/20260405125240.2558577-1-songmuchun@bytedance.com/)\n into this separate patchset, suggested by David.\n\nMuchun Song (6):\n mm/sparse-vmemmap: Fix vmemmap accounting underflow\n mm/sparse-vmemmap: Pass @pgmap argument to memory deactivation paths\n mm/sparse-vmemmap: Fix DAX vmemmap accounting with optimization\n mm/sparse-vmemmap: Pass @pgmap argument to arch vmemmap_populate()\n mm/sparse-vmemmap: Fix missing architecture-specific page table sync\n mm/mm_init: Fix pageblock migratetype for ZONE_DEVICE compound pages\n\n arch/arm64/mm/mmu.c | 11 +--\n arch/loongarch/mm/init.c | 12 +--\n arch/powerpc/include/asm/book3s/64/radix.h | 9 +--\n arch/powerpc/mm/book3s64/radix_pgtable.c | 18 +++--\n arch/powerpc/mm/init_64.c | 4 +-\n arch/powerpc/mm/mem.c | 5 +-\n arch/riscv/mm/init.c | 9 ++-\n arch/s390/mm/init.c | 5 +-\n arch/s390/mm/vmem.c | 2 +-\n arch/sparc/mm/init_64.c | 5 +-\n arch/x86/mm/init_64.c | 13 +--\n include/linux/memory_hotplug.h | 8 +-\n include/linux/mm.h | 8 +-\n mm/hugetlb_vmemmap.c | 4 +-\n mm/memory_hotplug.c | 12 +--\n mm/memremap.c | 4 +-\n mm/mm_init.c | 42 ++++++----\n mm/sparse-vmemmap.c | 93 ++++++++++++++--------\n 18 files changed, 160 insertions(+), 104 deletions(-)" }