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 5CBFD79CD for ; Thu, 17 Sep 2026 01:36:19 +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=1789608980; cv=none; b=dCMmR8ZfR3c9Q2uD3F/7iaQ8GFOfR189J6H6VRhHEr/pe3jiImdoxzb0Ysp3vPZAFODZiFQF6N8cVVDDkTEWjx8926MJakxGqhEs9gtjEVE9IDIz9LXxP8wXMsMFJkw20g65KkKrei1xQbEVcJ0rGY9zc9oemTF3rBf9a498oLw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789608980; c=relaxed/simple; bh=/C2zFd1nbuDiGKpyIgOjEmbSY1BUCGrPPSFHFMueLb8=; h=Date:To:From:Subject:Message-Id; b=RH9RUskQKSzOqPaFI3jM5yXP0AUwRZDzuWluYcboIlZuuysmVEoUr2prUoCa1RlE60nbmVxXXtDncXrqcIY3e08ktc90QQprOlOx9If6lzjbOm85Aj67bKMnOq4VkPnI7TObVuVv8JsdmBJItPMM/rb12Ei0SWoGqmV+8ntSFII= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=TE03KFZd; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="TE03KFZd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E959C1F000FF; Thu, 17 Sep 2026 01:36:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1789608979; bh=R4l21DLK5CYB8akxa9DyUVoYj1RFx88rXZ5hE4vwKKg=; h=Date:To:From:Subject; b=TE03KFZdUMgcrYPyj15zGtGeBSGnLHe/BFx3qANI0o52fDMjWQphIv1HusNAV/huq MPhEBqHvN7XfrGD+nQOYom9tkSV8QRkVVYHFEWSmQeEIBE5fEtdYEkno8UPTUmhh3R N5Q8wNMu3MpVxGmVTuCCYubof9rmq4S06wA33x2k= Date: Wed, 16 Sep 2026 18:36:18 -0700 To: mm-commits@vger.kernel.org,songmuchun@bytedance.com,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-sparse-vmemmap-introduce-config_vmemmap_optimization-fix.patch added to mm-unstable branch Message-Id: <20260917013618.E959C1F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm-sparse-vmemmap-introduce-config_vmemmap_optimization-fix has been added to the -mm mm-unstable branch. Its filename is mm-sparse-vmemmap-introduce-config_vmemmap_optimization-fix.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-sparse-vmemmap-introduce-config_vmemmap_optimization-fix.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: Muchun Song Subject: mm-sparse-vmemmap-introduce-config_vmemmap_optimization-fix Date: Wed, 16 Sep 2026 16:36:27 +0800 The section-based vmemmap optimization infrastructure is guarded by CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP, but it can also be used by ZONE_DEVICE users that set dev_pagemap::vmemmap_shift. Introduce CONFIG_VMEMMAP_OPTIMIZATION as a common config for the shared infrastructure. Select the new option from HUGETLB_PAGE_OPTIMIZE_VMEMMAP and from ZONE_DEVICE when the architecture opts in to DAX vmemmap optimization, and use it to guard the generic sparse-vmemmap state and helpers. Link: https://lore.kernel.org/20260916083627.2145779-1-songmuchun@bytedance.com Signed-off-by: Muchun Song Signed-off-by: Andrew Morton Acked-by: Qi Zheng Acked-by: Mike Rapoport (Microsoft) Cc: David Hildenbrand (Arm) Cc: Jonathan Corbet Cc: Lorenzo Stoakes Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Oscar Salvador Cc: Randy Dunlap --- drivers/dax/Kconfig | 2 -- mm/Kconfig | 1 + 2 files changed, 1 insertion(+), 2 deletions(-) --- a/drivers/dax/Kconfig~mm-sparse-vmemmap-introduce-config_vmemmap_optimization-fix +++ a/drivers/dax/Kconfig @@ -8,8 +8,6 @@ if DAX config DEV_DAX tristate "Device DAX: direct access mapping device" depends on TRANSPARENT_HUGEPAGE - depends on ZONE_DEVICE - select VMEMMAP_OPTIMIZATION if ARCH_WANT_OPTIMIZE_DAX_VMEMMAP help Support raw access to differentiated (persistence, bandwidth, latency...) memory via an mmap(2) capable character --- a/mm/Kconfig~mm-sparse-vmemmap-introduce-config_vmemmap_optimization-fix +++ a/mm/Kconfig @@ -1224,6 +1224,7 @@ config ZONE_DMA32 config ZONE_DEVICE bool "Device memory (pmem, HMM, etc...) hotplug support" depends on MEMORY_HOTREMOVE + select VMEMMAP_OPTIMIZATION if ARCH_WANT_OPTIMIZE_DAX_VMEMMAP select XARRAY_MULTI help _ Patches currently in -mm which might be from songmuchun@bytedance.com are mm-sparse-relax-struct-mem_section-size-constraints.patch mm-sparse-vmemmap-rename-hvo-order-macros.patch mm-mm_init-skip-initializing-shared-vmemmap-tail-pages.patch mm-sparse-vmemmap-initialize-shared-tail-vmemmap-pages-on-allocation.patch mm-sparse-vmemmap-support-section-based-vmemmap-accounting.patch mm-mm_init-factor-out-pfn_to_zone.patch mm-sparse-vmemmap-move-helpers-ahead-of-future-callers.patch mm-sparse-vmemmap-support-section-based-vmemmap-optimization.patch mm-sparse-initialize-memory-sections-earlier.patch mm-hugetlb-switch-hugetlb-to-section-based-vmemmap-optimization.patch mm-sparse-vmemmap-remove-sparsemem_vmemmap_preinit-support.patch mm-sparse-inline-usemap-allocation-into-sparse_init_nid.patch mm-sparse-remove-section_map_size.patch mm-hugetlb-remove-huge_bootmem_hvo.patch mm-hugetlb-remove-huge_bootmem_cma.patch mm-hugetlb-localize-struct-huge_bootmem_page.patch mm-hugetlb-localize-huge_bootmem_zones_valid.patch mm-sparse-vmemmap-introduce-config_vmemmap_optimization.patch mm-sparse-vmemmap-introduce-config_vmemmap_optimization-fix.patch mm-sparse-vmemmap-factor-out-shared-vmemmap-tail-page-allocation.patch mm-sparse-vmemmap-open-code-init_compound_tail.patch mm-sparse-vmemmap-prepare-dax-vmemmap-population-for-compound-page-orders.patch mm-sparse-vmemmap-set-compound-page-order-for-device-dax.patch mm-sparse-vmemmap-switch-device-dax-to-shared-tail-vmemmap-pages.patch mm-sparse-vmemmap-move-vmemmap-optimization-helpers-to-a-public-header.patch powerpc-mm-switch-device-dax-to-shared-tail-vmemmap-pages.patch mm-sparse-vmemmap-drop-the-extra-tail-page-from-device-dax-reservation.patch mm-sparse-vmemmap-drop-unused-section_nr_vmemmap_pages-arguments.patch documentation-mm-update-dax-vmemmap-deduplication-docs.patch