{"id":2223477,"url":"http://patchwork.ozlabs.org/api/1.2/covers/2223477/?format=json","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=json","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=json","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=json","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 ","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\" ,\n\tVlastimil Babka ,\n\tMike Rapoport ,\n\tSuren Baghdasaryan ,\n\tMichal Hocko ,\n\tNicholas Piggin ,\n\tChristophe Leroy ,\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 ","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":"","List-Help":"","List-Owner":"","List-Post":"","List-Archive":",\n ","List-Subscribe":",\n ,\n ","List-Unsubscribe":"","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(-)"}