From 4267739cabb82da75780c4699fe8208821929944 Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (Microsoft)" Date: Sun, 11 Jan 2026 10:20:58 +0200 Subject: [PATCH] arch, mm: consolidate initialization of SPARSE memory model 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 free_area_init() to ensure that vmemmap and HVO initialization order is always the same. Link: https://lkml.kernel.org/r/20260111082105.290734-25-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) Cc: Alexander Gordeev Cc: Alex Shi Cc: Andreas Larsson Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: David Hildenbrand Cc: David S. Miller Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: Huacai Chen Cc: Ingo Molnar Cc: Johannes Berg Cc: John Paul Adrian Glaubitz Cc: Jonathan Corbet Cc: Klara Modin Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Magnus Lindholm Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Hocko Cc: Michal Simek Cc: Muchun Song Cc: Oscar Salvador Cc: Palmer Dabbelt Cc: Pratyush Yadav Cc: Richard Weinberger Cc: "Ritesh Harjani (IBM)" Cc: Russell King Cc: Stafford Horne Cc: Suren Baghdasaryan Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vineet Gupta Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton --- 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 | 1 + 21 files changed, 11 insertions(+), 59 deletions(-) diff --git a/Documentation/mm/memory-model.rst b/Documentation/mm/memory-model.rst index 7957122039e87..199b11328f4fb 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 77ec149a970ca..c0c5d8ecd880a 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 bebdffafaee82..f0af444a69a40 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 a8f7b40847150..0cc1bf04686d8 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 3641e88ea871e..9d271aff76526 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 4bf3c01ead3a2..45c98dcf7f505 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 708ac025db71d..d6a1ff0e16f19 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 11b9b6b63e19f..d36d89d01fa48 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 ce6f09ab7a90d..6a39e031e5ff7 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 50a92b24628da..6d60ea4868ab8 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 b716c9cd141c9..3789a51bdaaee 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 603a0f652ba61..f4cf3ae036de9 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 79b4792578c46..11ac4041afc0e 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 9ec608b5cbb1c..3c20475cbee22 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 3edee854b7552..464a3a63e2fa5 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 931f872ce84a8..4f7bdb18774b8 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 b55172118c914..0908c44d51e6f 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 4daa40071c9fd..df2261fa4f985 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 fc5d6c88d2f01..eb3815fc94ad4 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -2286,9 +2286,7 @@ 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 9ee336aa03656..ecb6020cf3137 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -852,6 +852,12 @@ 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 6fb4415c0d1c8..31246fe5c3619 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -1825,6 +1825,7 @@ static void __init free_area_init(void) bool descending; arch_zone_limits_init(max_zone_pfn); + sparse_init(); start_pfn = PHYS_PFN(memblock_start_of_DRAM()); descending = arch_has_descending_max_zone_pfns(); -- 2.47.3