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 0C380D3B7E5 for ; Sun, 28 Dec 2025 12:46:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6E9496B00BB; Sun, 28 Dec 2025 07:46:00 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 69D2A6B00BD; Sun, 28 Dec 2025 07:46:00 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 57F0F6B00BE; Sun, 28 Dec 2025 07:46:00 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 420BB6B00BB for ; Sun, 28 Dec 2025 07:46:00 -0500 (EST) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id E430C189AEF for ; Sun, 28 Dec 2025 12:45:48 +0000 (UTC) X-FDA: 84268851576.01.B2C87C9 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf23.hostedemail.com (Postfix) with ESMTP id 4FE8E14000B for ; Sun, 28 Dec 2025 12:45:47 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=W8ovXZyK; spf=pass (imf23.hostedemail.com: domain of rppt@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1766925947; 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=R6E2XbBp7qoGv40BCObW0l1XGnLz9yIeSTt2/+/Pmew=; b=OkY3stXH0O2cFsLF74pLYCywUz7vQTex9BJUI1Ky6VQzyfQtUIQH5PP8aoazz8wDgMfDsb +lSFII5k1UxDqamhF+XRVau0okZTYcJienZnzdzJ4c0zcljDzzP5vB1GWIT+S9BO4Dluvb lnOp0u/tJqjvY6l/gLQiQak7gt/G9b0= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=W8ovXZyK; spf=pass (imf23.hostedemail.com: domain of rppt@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1766925947; a=rsa-sha256; cv=none; b=71qH+CcSnlFE5m4NLMm6m6zJZ4YEk1MM1DUC3XHNOoZQy/QRIC+yPUaEbHbh4TXDra/AvT UibjI3ajD+wiOzcHTQKZ/I4WcrnEo/6tTv1MxRgzjKfCV/+2SAimq6FnQ/PSjB+TpsJDq7 0HgxQNy1mW5rWsCfp1T09BR/04voTSw= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 87B87600AA; Sun, 28 Dec 2025 12:45:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6FB5C19421; Sun, 28 Dec 2025 12:45:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1766925946; bh=7OrsGKiYWf1/5FuSOQP615xNlPjZShIySrgunFegnEo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=W8ovXZyKrhZDx7hwiPJnBkkwmA3MbpIk8QA7gZPyPCnNvLGBP7YLM49+jgBdef82B D7yNoTQ8GvyrPUE3BR9VxrkmnZq/iWNYHfZ8mEo6hrdoYsQhl2wOYHRrXkQ1baFs3b XHzSAh8/+CPv5bV6W8IibueanbvC/OwsIT7uExxzMwm2X+87JWXupgI6LqJ5Qa7hMA HBLuLOOwoDfuy+mLrax6bbv+z4BGYQZTHUnFW3saKUNenmYy93a4OB6RkU6WsP0EnN T/Dw6dFK49+vp3VWFCwjaRvI6MiQqDmGuUXj9BhV2X79NImRlBvwjXRTMnkKLWVJd3 MM/E3dlY7rTQg== From: Mike Rapoport To: Andrew Morton Cc: Alex Shi , Alexander Gordeev , Andreas Larsson , Borislav Petkov , Brian Cain , "Christophe Leroy (CS GROUP)" , Catalin Marinas , "David S. Miller" , Dave Hansen , David Hildenbrand , Dinh Nguyen , Geert Uytterhoeven , Guo Ren , Heiko Carstens , Helge Deller , Huacai Chen , Ingo Molnar , Johannes Berg , John Paul Adrian Glaubitz , Jonathan Corbet , "Liam R. Howlett" , Lorenzo Stoakes , Magnus Lindholm , Matt Turner , Max Filippov , Michael Ellerman , Michal Hocko , Michal Simek , Mike Rapoport , Muchun Song , Oscar Salvador , Palmer Dabbelt , Pratyush Yadav , Richard Weinberger , Russell King , Stafford Horne , Suren Baghdasaryan , Thomas Bogendoerfer , Thomas Gleixner , Vasily Gorbik , Vineet Gupta , Vlastimil Babka , Will Deacon , x86@kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-cxl@vger.kernel.org, linux-doc@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-openrisc@vger.kernel.org, linux-parisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-um@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, loongarch@lists.linux.dev, sparclinux@vger.kernel.org Subject: [PATCH 23/28] arch, mm: consolidate initialization of SPARSE memory model Date: Sun, 28 Dec 2025 14:39:53 +0200 Message-ID: <20251228124001.3624742-24-rppt@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251228124001.3624742-1-rppt@kernel.org> References: <20251228124001.3624742-1-rppt@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Stat-Signature: g9zob57jjeehn86rczowf4sg9ofy5akh X-Rspam-User: X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 4FE8E14000B X-HE-Tag: 1766925947-204696 X-HE-Meta: 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 7WpR9WV1 wbnjOgdpDPTGNdyIW3uLwv4v3jmHUg76U5oXyJcbRdbYlOUD4bvazXpmIXE7K9iSaascBN7Qi4W0+n00J1ajOL+f0fGWLlhY6hp23HfI+aE+EZV8eV7WtVOJ1bFNa/TFlQgtLU/kB4+RHpKVDp9KCnnkJ+clsaTliGU18N0aorffDsz6KPLlLgWE0NWH3Sx9sA7o9M2fOxBQkU79DdaGX75JYAha2lle9M8ZUJADAZ+PCqlJd8TSyvhthxiXpeNWci4qUKvjjxIqXxiE= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: "Mike Rapoport (Microsoft)" Every architecture calls sparse_init() during setup_arch() although the data structures created by sparse_init() are not used until the initialization of the core MM. Beside the code duplication, calling sparse_init() from architecture specific code causes ordering differences of vmemmap and HVO initialization on different architectures. Move the call to sparse_init() from architecture specific code to mm_core_init() to ensure that vmemmap and HVO initialization order is always the same. Signed-off-by: Mike Rapoport (Microsoft) --- Documentation/mm/memory-model.rst | 3 --- Documentation/translations/zh_CN/mm/memory-model.rst | 2 -- arch/alpha/kernel/setup.c | 1 - arch/arm/mm/init.c | 6 ------ arch/arm64/mm/init.c | 6 ------ arch/csky/kernel/setup.c | 2 -- arch/loongarch/kernel/setup.c | 8 -------- arch/mips/kernel/setup.c | 11 ----------- arch/parisc/mm/init.c | 2 -- arch/powerpc/include/asm/setup.h | 4 ++++ arch/powerpc/mm/mem.c | 5 ----- arch/powerpc/mm/numa.c | 2 -- arch/riscv/mm/init.c | 1 - arch/s390/mm/init.c | 1 - arch/sh/mm/init.c | 2 -- arch/sparc/mm/init_64.c | 2 -- arch/x86/mm/init_32.c | 1 - arch/x86/mm/init_64.c | 2 -- include/linux/mmzone.h | 2 -- mm/internal.h | 6 ++++++ mm/mm_init.c | 2 ++ 21 files changed, 12 insertions(+), 59 deletions(-) diff --git a/Documentation/mm/memory-model.rst b/Documentation/mm/memory-model.rst index 7957122039e8..199b11328f4f 100644 --- a/Documentation/mm/memory-model.rst +++ b/Documentation/mm/memory-model.rst @@ -97,9 +97,6 @@ sections: `mem_section` objects and the number of rows is calculated to fit all the memory sections. -The architecture setup code should call sparse_init() to -initialize the memory sections and the memory maps. - With SPARSEMEM there are two possible ways to convert a PFN to the corresponding `struct page` - a "classic sparse" and "sparse vmemmap". The selection is made at build time and it is determined by diff --git a/Documentation/translations/zh_CN/mm/memory-model.rst b/Documentation/translations/zh_CN/mm/memory-model.rst index 77ec149a970c..c0c5d8ecd880 100644 --- a/Documentation/translations/zh_CN/mm/memory-model.rst +++ b/Documentation/translations/zh_CN/mm/memory-model.rst @@ -83,8 +83,6 @@ SPARSEMEM模型将物理内存显示为一个部分的集合。一个区段用me 每一行包含价值 `PAGE_SIZE` 的 `mem_section` 对象，行数的计算是为了适应所有的 内存区。 -架构设置代码应该调用sparse_init()来初始化内存区和内存映射。 - 通过SPARSEMEM，有两种可能的方式将PFN转换为相应的 `struct page` --"classic sparse"和 "sparse vmemmap"。选择是在构建时进行的，它由 `CONFIG_SPARSEMEM_VMEMMAP` 的 值决定。 diff --git a/arch/alpha/kernel/setup.c b/arch/alpha/kernel/setup.c index bebdffafaee8..f0af444a69a4 100644 --- a/arch/alpha/kernel/setup.c +++ b/arch/alpha/kernel/setup.c @@ -607,7 +607,6 @@ setup_arch(char **cmdline_p) /* Find our memory. */ setup_memory(kernel_end); memblock_set_bottom_up(true); - sparse_init(); /* First guess at cpu cache sizes. Do this before init_arch. */ determine_cpu_caches(cpu->type); diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index a8f7b4084715..0cc1bf04686d 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -207,12 +207,6 @@ void __init bootmem_init(void) early_memtest((phys_addr_t)min_low_pfn << PAGE_SHIFT, (phys_addr_t)max_low_pfn << PAGE_SHIFT); - - /* - * sparse_init() tries to allocate memory from memblock, so must be - * done after the fixed reservations - */ - sparse_init(); } /* diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 3641e88ea871..9d271aff7652 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -321,12 +321,6 @@ void __init bootmem_init(void) #endif kvm_hyp_reserve(); - - /* - * sparse_init() tries to allocate memory from memblock, so must be - * done after the fixed reservations - */ - sparse_init(); dma_limits_init(); /* diff --git a/arch/csky/kernel/setup.c b/arch/csky/kernel/setup.c index 4bf3c01ead3a..45c98dcf7f50 100644 --- a/arch/csky/kernel/setup.c +++ b/arch/csky/kernel/setup.c @@ -123,8 +123,6 @@ void __init setup_arch(char **cmdline_p) setup_smp(); #endif - sparse_init(); - fixaddr_init(); #ifdef CONFIG_HIGHMEM diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c index 708ac025db71..d6a1ff0e16f1 100644 --- a/arch/loongarch/kernel/setup.c +++ b/arch/loongarch/kernel/setup.c @@ -402,14 +402,6 @@ static void __init arch_mem_init(char **cmdline_p) check_kernel_sections_mem(); - /* - * In order to reduce the possibility of kernel panic when failed to - * get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate - * low memory as small as possible before swiotlb_init(), so make - * sparse_init() using top-down allocation. - */ - memblock_set_bottom_up(false); - sparse_init(); memblock_set_bottom_up(true); swiotlb_init(true, SWIOTLB_VERBOSE); diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index 11b9b6b63e19..d36d89d01fa4 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -614,7 +614,6 @@ static void __init bootcmdline_init(void) * kernel but generic memory management system is still entirely uninitialized. * * o bootmem_init() - * o sparse_init() * o paging_init() * o dma_contiguous_reserve() * @@ -665,16 +664,6 @@ static void __init arch_mem_init(char **cmdline_p) mips_parse_crashkernel(); device_tree_init(); - /* - * In order to reduce the possibility of kernel panic when failed to - * get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate - * low memory as small as possible before plat_swiotlb_setup(), so - * make sparse_init() using top-down allocation. - */ - memblock_set_bottom_up(false); - sparse_init(); - memblock_set_bottom_up(true); - plat_swiotlb_setup(); dma_contiguous_reserve(PFN_PHYS(max_low_pfn)); diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c index ce6f09ab7a90..6a39e031e5ff 100644 --- a/arch/parisc/mm/init.c +++ b/arch/parisc/mm/init.c @@ -706,8 +706,6 @@ void __init paging_init(void) fixmap_init(); flush_cache_all_local(); /* start with known state */ flush_tlb_all_local(NULL); - - sparse_init(); } static void alloc_btlb(unsigned long start, unsigned long end, int *slot, diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h index 50a92b24628d..6d60ea4868ab 100644 --- a/arch/powerpc/include/asm/setup.h +++ b/arch/powerpc/include/asm/setup.h @@ -20,7 +20,11 @@ extern void reloc_got2(unsigned long); void check_for_initrd(void); void mem_topology_setup(void); +#ifdef CONFIG_NUMA void initmem_init(void); +#else +static inline void initmem_init(void) {} +#endif void setup_panic(void); #define ARCH_PANIC_TIMEOUT 180 diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 72d4993192a6..30f56d601e56 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -182,11 +182,6 @@ void __init mem_topology_setup(void) memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); } -void __init initmem_init(void) -{ - sparse_init(); -} - /* mark pages that don't exist as nosave */ static int __init mark_nonram_nosave(void) { diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 603a0f652ba6..f4cf3ae036de 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1213,8 +1213,6 @@ void __init initmem_init(void) setup_node_data(nid, start_pfn, end_pfn); } - sparse_init(); - /* * We need the numa_cpu_lookup_table to be accurate for all CPUs, * even before we online them, so that we can use cpu_to_{node,mem} diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 79b4792578c4..11ac4041afc0 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -1430,7 +1430,6 @@ void __init misc_mem_init(void) { early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); arch_numa_init(); - sparse_init(); #ifdef CONFIG_SPARSEMEM_VMEMMAP /* The entire VMEMMAP region has been populated. Flush TLB for this region */ local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END); diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 9ec608b5cbb1..3c20475cbee2 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -98,7 +98,6 @@ void __init arch_zone_limits_init(unsigned long *max_zone_pfns) void __init paging_init(void) { vmem_map_init(); - sparse_init(); zone_dma_limit = DMA_BIT_MASK(31); } diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c index 3edee854b755..464a3a63e2fa 100644 --- a/arch/sh/mm/init.c +++ b/arch/sh/mm/init.c @@ -227,8 +227,6 @@ static void __init do_init_bootmem(void) node_set_online(0); plat_mem_setup(); - - sparse_init(); } static void __init early_reserve_mem(void) diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c index 931f872ce84a..4f7bdb18774b 100644 --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -1615,8 +1615,6 @@ static unsigned long __init bootmem_init(unsigned long phys_base) /* XXX cpu notifier XXX */ - sparse_init(); - return end_pfn; } diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index b55172118c91..0908c44d51e6 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -654,7 +654,6 @@ void __init paging_init(void) * NOTE: at this point the bootmem allocator is fully available. */ olpc_dt_build_devicetree(); - sparse_init(); } /* diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 4daa40071c9f..df2261fa4f98 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -833,8 +833,6 @@ void __init initmem_init(void) void __init paging_init(void) { - sparse_init(); - /* * clear the default setting with node 0 * note: don't use nodes_clear here, that is really clearing when diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 75ef7c9f9307..6a7db0fee54a 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -2285,9 +2285,7 @@ static inline unsigned long next_present_section_nr(unsigned long section_nr) #define pfn_to_nid(pfn) (0) #endif -void sparse_init(void); #else -#define sparse_init() do {} while (0) #define sparse_index_init(_sec, _nid) do {} while (0) #define sparse_vmemmap_init_nid_early(_nid) do {} while (0) #define sparse_vmemmap_init_nid_late(_nid) do {} while (0) diff --git a/mm/internal.h b/mm/internal.h index e430da900430..dc5316c68664 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -860,6 +860,12 @@ void memmap_init_range(unsigned long, int, unsigned long, unsigned long, unsigned long, enum meminit_context, struct vmem_altmap *, int, bool); +#ifdef CONFIG_SPARSEMEM +void sparse_init(void); +#else +static inline void sparse_init(void) {} +#endif /* CONFIG_SPARSEMEM */ + #if defined CONFIG_COMPACTION || defined CONFIG_CMA /* diff --git a/mm/mm_init.c b/mm/mm_init.c index 43ef7a3501b9..027d53073393 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -1900,6 +1900,8 @@ static void __init free_area_init(void) unsigned long start_pfn, end_pfn; int i, nid; + sparse_init(); + /* * Initialize the subsection-map relative to active online memory * ranges to enable future "sub-section" extensions of the memory map. -- 2.51.0