Re: [PATCH v3 3/4] arch, mm: consolidate empty_zero_page

Liam R. Howlett
2026-02-12T18:39:19Z

* Mike Rapoport <rppt@kernel.org> [260211 05:32]:
> From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
>
> Reduce 22 declarations of empty_zero_page to 3 and 23 declarations of
> ZERO_PAGE() to 4.
>
> Every architecture defines empty_zero_page that way or another, but for the
> most of them it is always a page aligned page in BSS and most definitions
> of ZERO_PAGE do virt_to_page(empty_zero_page).
>
> Move Linus vetted x86 definition of empty_zero_page and ZERO_PAGE() to the
> core MM and drop these definitions in architectures that do not implement
> colored zero page (MIPS and s390).
>
> ZERO_PAGE() remains a macro because turning it to a wrapper for a static
> inline causes severe pain in header dependencies.
>
> For the most part the change is mechanical, with these being noteworthy:
>
> * alpha: aliased empty_zero_page with ZERO_PGE that was also used for boot
> parameters. Switching to a generic empty_zero_page removes the aliasing
> and keeps ZERO_PGE for boot parameters only
> * arm64: uses __pa_symbol() in ZERO_PAGE() so that definition of
> ZERO_PAGE() is kept intact.
> * m68k/parisc/um: allocated empty_zero_page from memblock,
> although they do not support zero page coloring and having it in BSS
> will work fine.
> * sparc64 can have empty_zero_page in BSS rather allocate it, but it
> can't use virt_to_page() for BSS. Keep it's definition of ZERO_PAGE()
> but instead of allocating it, make mem_map_zero point to
> empty_zero_page.
> * sh: used empty_zero_page for boot parameters at the very early boot.
> Rename the parameters page to boot_params_page and let sh use the generic
> empty_zero_page.
> * hexagon: had an amusing comment about empty_zero_page
>
> /* A handy thing to have if one has the RAM. Declared in head.S */
>
> that unfortunately had to go :)
>
> Acked-by: Helge Deller <deller@gmx.de> # parisc
> Tested-by: Helge Deller <deller@gmx.de> # parisc
> Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
> Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com>

> ---
> arch/alpha/include/asm/pgtable.h | 6 ------
> arch/arc/include/asm/pgtable.h | 3 ---
> arch/arc/mm/init.c | 2 --
> arch/arm/include/asm/pgtable.h | 9 ---------
> arch/arm/mm/mmu.c | 7 -------
> arch/arm/mm/nommu.c | 7 -------
> arch/arm64/include/asm/pgtable.h | 1 -
> arch/arm64/mm/mmu.c | 7 -------
> arch/csky/include/asm/pgtable.h | 3 ---
> arch/csky/mm/init.c | 3 ---
> arch/hexagon/include/asm/pgtable.h | 6 ------
> arch/hexagon/kernel/head.S | 5 -----
> arch/hexagon/kernel/hexagon_ksyms.c | 1 -
> arch/loongarch/include/asm/pgtable.h | 9 ---------
> arch/loongarch/mm/init.c | 3 ---
> arch/m68k/include/asm/pgtable_mm.h | 9 ---------
> arch/m68k/include/asm/pgtable_no.h | 7 -------
> arch/m68k/mm/init.c | 9 ---------
> arch/m68k/mm/mcfmmu.c | 2 --
> arch/m68k/mm/motorola.c | 6 ------
> arch/m68k/mm/sun3mmu.c | 2 --
> arch/microblaze/include/asm/pgtable.h | 10 ----------
> arch/microblaze/kernel/head.S | 4 ----
> arch/microblaze/kernel/microblaze_ksyms.c | 2 --
> arch/nios2/include/asm/pgtable.h | 7 -------
> arch/nios2/kernel/head.S | 10 ----------
> arch/nios2/kernel/nios2_ksyms.c | 1 -
> arch/openrisc/include/asm/pgtable.h | 4 ----
> arch/openrisc/kernel/head.S | 3 ---
> arch/openrisc/kernel/or32_ksyms.c | 1 -
> arch/openrisc/mm/init.c | 3 ---
> arch/parisc/include/asm/pgtable.h | 11 -----------
> arch/parisc/mm/init.c | 6 ------
> arch/powerpc/include/asm/pgtable.h | 6 ------
> arch/powerpc/mm/mem.c | 3 ---
> arch/riscv/include/asm/pgtable.h | 7 -------
> arch/riscv/mm/init.c | 4 ----
> arch/sh/include/asm/pgtable.h | 8 --------
> arch/sh/include/asm/setup.h | 3 ++-
> arch/sh/kernel/head_32.S | 4 ++--
> arch/sh/kernel/sh_ksyms_32.c | 1 -
> arch/sh/mm/init.c | 1 -
> arch/sparc/include/asm/pgtable_32.h | 8 --------
> arch/sparc/include/asm/setup.h | 2 --
> arch/sparc/kernel/head_32.S | 7 -------
> arch/sparc/mm/init_32.c | 4 ----
> arch/sparc/mm/init_64.c | 11 ++++-------
> arch/um/include/asm/pgtable.h | 9 ---------
> arch/um/include/shared/kern_util.h | 1 -
> arch/um/kernel/mem.c | 16 ----------------
> arch/um/kernel/um_arch.c | 1 -
> arch/x86/include/asm/pgtable.h | 8 --------
> arch/x86/kernel/head_32.S | 4 ----
> arch/x86/kernel/head_64.S | 7 -------
> arch/xtensa/include/asm/pgtable.h | 4 ----
> arch/xtensa/kernel/head.S | 3 ---
> arch/xtensa/kernel/xtensa_ksyms.c | 2 --
> include/linux/pgtable.h | 10 ++++++++++
> mm/mm_init.c | 5 +++++
> 59 files changed, 23 insertions(+), 285 deletions(-)
>
> diff --git a/arch/alpha/include/asm/pgtable.h b/arch/alpha/include/asm/pgtable.h
> index 90e7a9539102..12a3c5f8ece8 100644
> --- a/arch/alpha/include/asm/pgtable.h
> +++ b/arch/alpha/include/asm/pgtable.h
> @@ -125,12 +125,6 @@ struct vm_area_struct;
> */
> #define pgprot_noncached(prot) (prot)
>
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -#define ZERO_PAGE(vaddr) (virt_to_page(ZERO_PGE))
> -
> /*
> * On certain platforms whose physical address space can overlap KSEG,
> * namely EV6 and above, we must re-twiddle the physaddr to restore the
> diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h
> index bd580e2b62d7..0fdaea81b5fa 100644
> --- a/arch/arc/include/asm/pgtable.h
> +++ b/arch/arc/include/asm/pgtable.h
> @@ -21,9 +21,6 @@
>
> #ifndef __ASSEMBLER__
>
> -extern char empty_zero_page[PAGE_SIZE];
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> extern pgd_t swapper_pg_dir[] __aligned(PAGE_SIZE);
>
> /* to cope with aliasing VIPT cache */
> diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
> index a5e92f46e5d1..d6b5c27a0098 100644
> --- a/arch/arc/mm/init.c
> +++ b/arch/arc/mm/init.c
> @@ -19,8 +19,6 @@
> #include <asm/arcregs.h>
>
> pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE);
> -char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE);
> -EXPORT_SYMBOL(empty_zero_page);
>
> static const unsigned long low_mem_start = CONFIG_LINUX_RAM_BASE;
> static unsigned long low_mem_sz;
> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
> index 6fa9acd6a7f5..982795cf4563 100644
> --- a/arch/arm/include/asm/pgtable.h
> +++ b/arch/arm/include/asm/pgtable.h
> @@ -10,15 +10,6 @@
> #include <linux/const.h>
> #include <asm/proc-fns.h>
>
> -#ifndef __ASSEMBLY__
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -#endif
> -
> #include <asm-generic/pgtable-nopud.h>
>
> #ifndef CONFIG_MMU
> diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
> index 518def8314e7..23b87b5ef7f1 100644
> --- a/arch/arm/mm/mmu.c
> +++ b/arch/arm/mm/mmu.c
> @@ -41,13 +41,6 @@
>
> extern unsigned long __atags_pointer;
>
> -/*
> - * empty_zero_page is a special page that is used for
> - * zero-initialized data and COW.
> - */
> -unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
> -EXPORT_SYMBOL(empty_zero_page);
> -
> /*
> * The pmd table for the upper-most set of pages.
> */
> diff --git a/arch/arm/mm/nommu.c b/arch/arm/mm/nommu.c
> index 7e42d8accec6..040ea43cce32 100644
> --- a/arch/arm/mm/nommu.c
> +++ b/arch/arm/mm/nommu.c
> @@ -27,13 +27,6 @@
>
> unsigned long vectors_base;
>
> -/*
> - * empty_zero_page is a special page that is used for
> - * zero-initialized data and COW.
> - */
> -unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
> -EXPORT_SYMBOL(empty_zero_page);
> -
> #ifdef CONFIG_ARM_MPU
> struct mpu_rgn_info mpu_rgn_info;
> #endif
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index d94445b4f3df..63da07398a30 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -110,7 +110,6 @@ static inline void arch_leave_lazy_mmu_mode(void)
> * ZERO_PAGE is a global shared page that is always zero: used
> * for zero-mapped memory areas etc..
> */
> -extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
> #define ZERO_PAGE(vaddr) phys_to_page(__pa_symbol(empty_zero_page))
>
> #define pte_ERROR(e) \
> diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
> index a6a00accf4f9..0f6a171faf1f 100644
> --- a/arch/arm64/mm/mmu.c
> +++ b/arch/arm64/mm/mmu.c
> @@ -64,13 +64,6 @@ static bool rodata_is_rw __ro_after_init = true;
> */
> long __section(".mmuoff.data.write") __early_cpu_boot_status;
>
> -/*
> - * Empty_zero_page is a special page that is used for zero-initialized data
> - * and COW.
> - */
> -unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
> -EXPORT_SYMBOL(empty_zero_page);
> -
> static DEFINE_SPINLOCK(swapper_pgdir_lock);
> static DEFINE_MUTEX(fixmap_lock);
>
> diff --git a/arch/csky/include/asm/pgtable.h b/arch/csky/include/asm/pgtable.h
> index d606afbabce1..bafcd5823531 100644
> --- a/arch/csky/include/asm/pgtable.h
> +++ b/arch/csky/include/asm/pgtable.h
> @@ -76,9 +76,6 @@
> #define MAX_SWAPFILES_CHECK() \
> BUILD_BUG_ON(MAX_SWAPFILES_SHIFT != 5)
>
> -extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> extern void load_pgd(unsigned long pg_dir);
> extern pte_t invalid_pte_table[PTRS_PER_PTE];
>
> diff --git a/arch/csky/mm/init.c b/arch/csky/mm/init.c
> index 573da66b2543..fa16015ea1c0 100644
> --- a/arch/csky/mm/init.c
> +++ b/arch/csky/mm/init.c
> @@ -38,9 +38,6 @@ pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
> pte_t kernel_pte_tables[PTRS_KERN_TABLE] __page_aligned_bss;
>
> EXPORT_SYMBOL(invalid_pte_table);
> -unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
> - __page_aligned_bss;
> -EXPORT_SYMBOL(empty_zero_page);
>
> void free_initmem(void)
> {
> diff --git a/arch/hexagon/include/asm/pgtable.h b/arch/hexagon/include/asm/pgtable.h
> index fbf24d1d1ca6..27b269e2870d 100644
> --- a/arch/hexagon/include/asm/pgtable.h
> +++ b/arch/hexagon/include/asm/pgtable.h
> @@ -14,9 +14,6 @@
> #include <asm/page.h>
> #include <asm-generic/pgtable-nopmd.h>
>
> -/* A handy thing to have if one has the RAM. Declared in head.S */
> -extern unsigned long empty_zero_page;
> -
> /*
> * The PTE model described here is that of the Hexagon Virtual Machine,
> * which autonomously walks 2-level page tables. At a lower level, we
> @@ -348,9 +345,6 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd)
> return (unsigned long)__va(pmd_val(pmd) & PAGE_MASK);
> }
>
> -/* ZERO_PAGE - returns the globally shared zero page */
> -#define ZERO_PAGE(vaddr) (virt_to_page(&empty_zero_page))
> -
> /*
> * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
> * are !pte_none() && !pte_present().
> diff --git a/arch/hexagon/kernel/head.S b/arch/hexagon/kernel/head.S
> index 0b016308cc79..908ffece9132 100644
> --- a/arch/hexagon/kernel/head.S
> +++ b/arch/hexagon/kernel/head.S
> @@ -216,8 +216,3 @@ __head_s_vaddr_target:
> .p2align PAGE_SHIFT
> ENTRY(external_cmdline_buffer)
> .fill _PAGE_SIZE,1,0
> -
> -.data
> -.p2align PAGE_SHIFT
> -ENTRY(empty_zero_page)
> - .fill _PAGE_SIZE,1,0
> diff --git a/arch/hexagon/kernel/hexagon_ksyms.c b/arch/hexagon/kernel/hexagon_ksyms.c
> index 36a80e31d187..81bc6f81e200 100644
> --- a/arch/hexagon/kernel/hexagon_ksyms.c
> +++ b/arch/hexagon/kernel/hexagon_ksyms.c
> @@ -17,7 +17,6 @@ EXPORT_SYMBOL(raw_copy_to_user);
> EXPORT_SYMBOL(__vmgetie);
> EXPORT_SYMBOL(__vmsetie);
> EXPORT_SYMBOL(__vmyield);
> -EXPORT_SYMBOL(empty_zero_page);
> EXPORT_SYMBOL(memcpy);
> EXPORT_SYMBOL(memset);
>
> diff --git a/arch/loongarch/include/asm/pgtable.h b/arch/loongarch/include/asm/pgtable.h
> index c33b3bcb733e..a244de27a03e 100644
> --- a/arch/loongarch/include/asm/pgtable.h
> +++ b/arch/loongarch/include/asm/pgtable.h
> @@ -74,15 +74,6 @@
> struct mm_struct;
> struct vm_area_struct;
>
> -/*
> - * ZERO_PAGE is a global shared page that is always zero; used
> - * for zero-mapped memory areas etc..
> - */
> -
> -extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
> -
> -#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
> -
> #ifdef CONFIG_32BIT
>
> #define VMALLOC_START (vm_map_base + PCI_IOSIZE + (2 * PAGE_SIZE))
> diff --git a/arch/loongarch/mm/init.c b/arch/loongarch/mm/init.c
> index c331bf69d2ec..00f3822b6e47 100644
> --- a/arch/loongarch/mm/init.c
> +++ b/arch/loongarch/mm/init.c
> @@ -36,9 +36,6 @@
> #include <asm/pgalloc.h>
> #include <asm/tlb.h>
>
> -unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
> -EXPORT_SYMBOL(empty_zero_page);
> -
> void copy_user_highpage(struct page *to, struct page *from,
> unsigned long vaddr, struct vm_area_struct *vma)
> {
> diff --git a/arch/m68k/include/asm/pgtable_mm.h b/arch/m68k/include/asm/pgtable_mm.h
> index bba64a9c49ac..7501ff030c63 100644
> --- a/arch/m68k/include/asm/pgtable_mm.h
> +++ b/arch/m68k/include/asm/pgtable_mm.h
> @@ -110,15 +110,6 @@ extern unsigned long m68k_vmalloc_end;
> #define VMALLOC_END KMAP_START
> #endif
>
> -/* zero page used for uninitialized stuff */
> -extern void *empty_zero_page;
> -
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> extern void kernel_set_cachemode(void *addr, unsigned long size, int cmode);
>
> /*
> diff --git a/arch/m68k/include/asm/pgtable_no.h b/arch/m68k/include/asm/pgtable_no.h
> index 1a86c15b9008..11751807a3f3 100644
> --- a/arch/m68k/include/asm/pgtable_no.h
> +++ b/arch/m68k/include/asm/pgtable_no.h
> @@ -30,13 +30,6 @@
>
> #define swapper_pg_dir ((pgd_t *) 0)
>
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -extern void *empty_zero_page;
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> /*
> * All 32bit addresses are effectively valid for vmalloc...
> * Sort of meaningless for non-VM targets.
> diff --git a/arch/m68k/mm/init.c b/arch/m68k/mm/init.c
> index 53b71f786c27..3b88c0dd1616 100644
> --- a/arch/m68k/mm/init.c
> +++ b/arch/m68k/mm/init.c
> @@ -33,13 +33,6 @@
> #include <asm/sections.h>
> #include <asm/tlb.h>
>
> -/*
> - * ZERO_PAGE is a special page that is used for zero-initialized
> - * data and COW.
> - */
> -void *empty_zero_page;
> -EXPORT_SYMBOL(empty_zero_page);
> -
> void __init arch_zone_limits_init(unsigned long *max_zone_pfns)
> {
> max_zone_pfns[ZONE_DMA] = PFN_DOWN(memblock_end_of_DRAM());
> @@ -71,8 +64,6 @@ void __init paging_init(void)
> unsigned long end_mem = memory_end & PAGE_MASK;
>
> high_memory = (void *) end_mem;
> -
> - empty_zero_page = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
> }
>
> #endif /* CONFIG_MMU */
> diff --git a/arch/m68k/mm/mcfmmu.c b/arch/m68k/mm/mcfmmu.c
> index 3418fd864237..4924f2ff8ef8 100644
> --- a/arch/m68k/mm/mcfmmu.c
> +++ b/arch/m68k/mm/mcfmmu.c
> @@ -41,8 +41,6 @@ void __init paging_init(void)
> unsigned long next_pgtable;
> int i;
>
> - empty_zero_page = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
> -
> pg_dir = swapper_pg_dir;
> memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
>
> diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c
> index 127a3fa69f4c..b30aa69a73a6 100644
> --- a/arch/m68k/mm/motorola.c
> +++ b/arch/m68k/mm/motorola.c
> @@ -498,12 +498,6 @@ void __init paging_init(void)
>
> early_memtest(min_addr, max_addr);
>
> - /*
> - * initialize the bad page table and bad page to point
> - * to a couple of allocated pages
> - */
> - empty_zero_page = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
> -
> /*
> * Set up SFC/DFC registers
> */
> diff --git a/arch/m68k/mm/sun3mmu.c b/arch/m68k/mm/sun3mmu.c
> index c801677f7df8..f139cc15753a 100644
> --- a/arch/m68k/mm/sun3mmu.c
> +++ b/arch/m68k/mm/sun3mmu.c
> @@ -43,8 +43,6 @@ void __init paging_init(void)
> unsigned long bootmem_end;
> unsigned long size;
>
> - empty_zero_page = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
> -
> address = PAGE_OFFSET;
> pg_dir = swapper_pg_dir;
> memset (swapper_pg_dir, 0, sizeof (swapper_pg_dir));
> diff --git a/arch/microblaze/include/asm/pgtable.h b/arch/microblaze/include/asm/pgtable.h
> index 4eb76de6be4a..ea72291de553 100644
> --- a/arch/microblaze/include/asm/pgtable.h
> +++ b/arch/microblaze/include/asm/pgtable.h
> @@ -207,16 +207,6 @@ extern pte_t *va_to_pte(unsigned long address);
> * Also, write permissions imply read permissions.
> */
>
> -#ifndef __ASSEMBLER__
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -extern unsigned long empty_zero_page[1024];
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> -#endif /* __ASSEMBLER__ */
> -
> #define pte_none(pte) ((pte_val(pte) & ~_PTE_NONE_MASK) == 0)
> #define pte_present(pte) (pte_val(pte) & _PAGE_PRESENT)
> #define pte_clear(mm, addr, ptep) \
> diff --git a/arch/microblaze/kernel/head.S b/arch/microblaze/kernel/head.S
> index ec2fcb545e64..808019c3b7ac 100644
> --- a/arch/microblaze/kernel/head.S
> +++ b/arch/microblaze/kernel/head.S
> @@ -39,10 +39,6 @@
> #include <asm/processor.h>
>
> .section .data
> -.global empty_zero_page
> -.align 12
> -empty_zero_page:
> - .space PAGE_SIZE
> .global swapper_pg_dir
> swapper_pg_dir:
> .space PAGE_SIZE
> diff --git a/arch/microblaze/kernel/microblaze_ksyms.c b/arch/microblaze/kernel/microblaze_ksyms.c
> index a8553f54152b..ad7596d7ba07 100644
> --- a/arch/microblaze/kernel/microblaze_ksyms.c
> +++ b/arch/microblaze/kernel/microblaze_ksyms.c
> @@ -33,8 +33,6 @@ EXPORT_SYMBOL(memcpy);
> EXPORT_SYMBOL(memmove);
> #endif
>
> -EXPORT_SYMBOL(empty_zero_page);
> -
> EXPORT_SYMBOL(mbc);
>
> extern void __divsi3(void);
> diff --git a/arch/nios2/include/asm/pgtable.h b/arch/nios2/include/asm/pgtable.h
> index 844dce55569f..d389aa9ca57c 100644
> --- a/arch/nios2/include/asm/pgtable.h
> +++ b/arch/nios2/include/asm/pgtable.h
> @@ -65,13 +65,6 @@ struct mm_struct;
> #define PGDIR_SIZE (1UL << PGDIR_SHIFT)
> #define PGDIR_MASK (~(PGDIR_SIZE-1))
>
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
> extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)];
>
> diff --git a/arch/nios2/kernel/head.S b/arch/nios2/kernel/head.S
> index 372ce4a33018..613212e1a63a 100644
> --- a/arch/nios2/kernel/head.S
> +++ b/arch/nios2/kernel/head.S
> @@ -23,16 +23,6 @@
> #include <asm/asm-offsets.h>
> #include <asm/asm-macros.h>
>
> -/*
> - * ZERO_PAGE is a special page that is used for zero-initialized
> - * data and COW.
> - */
> -.data
> -.global empty_zero_page
> -.align 12
> -empty_zero_page:
> - .space PAGE_SIZE
> -
> /*
> * This global variable is used as an extension to the nios'
> * STATUS register to emulate a user/supervisor mode.
> diff --git a/arch/nios2/kernel/nios2_ksyms.c b/arch/nios2/kernel/nios2_ksyms.c
> index 54f7b23df1bf..c40aa39e8658 100644
> --- a/arch/nios2/kernel/nios2_ksyms.c
> +++ b/arch/nios2/kernel/nios2_ksyms.c
> @@ -20,7 +20,6 @@ EXPORT_SYMBOL(memmove);
>
> /* memory management */
>
> -EXPORT_SYMBOL(empty_zero_page);
> EXPORT_SYMBOL(flush_icache_range);
>
> /*
> diff --git a/arch/openrisc/include/asm/pgtable.h b/arch/openrisc/include/asm/pgtable.h
> index b218050e2f6d..6b89996d0b62 100644
> --- a/arch/openrisc/include/asm/pgtable.h
> +++ b/arch/openrisc/include/asm/pgtable.h
> @@ -179,10 +179,6 @@ extern void paging_init(void);
> __pgprot(_PAGE_ALL | _PAGE_SRE | _PAGE_SWE \
> | _PAGE_SHARED | _PAGE_DIRTY | _PAGE_EXEC | _PAGE_CI)
>
> -/* zero page used for uninitialized stuff */
> -extern unsigned long empty_zero_page[2048];
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> #define pte_none(x) (!pte_val(x))
> #define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
> #define pte_clear(mm, addr, xp) do { pte_val(*(xp)) = 0; } while (0)
> diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
> index bd760066f1cd..45890393947d 100644
> --- a/arch/openrisc/kernel/head.S
> +++ b/arch/openrisc/kernel/head.S
> @@ -1563,9 +1563,6 @@ _string_nl:
> */
> .section .data,"aw"
> .align 8192
> - .global empty_zero_page
> -empty_zero_page:
> - .space 8192
>
> .global swapper_pg_dir
> swapper_pg_dir:
> diff --git a/arch/openrisc/kernel/or32_ksyms.c b/arch/openrisc/kernel/or32_ksyms.c
> index 212e5f85004c..84a937a64e2a 100644
> --- a/arch/openrisc/kernel/or32_ksyms.c
> +++ b/arch/openrisc/kernel/or32_ksyms.c
> @@ -40,7 +40,6 @@ DECLARE_EXPORT(__ashldi3);
> DECLARE_EXPORT(__lshrdi3);
> DECLARE_EXPORT(__ucmpdi2);
>
> -EXPORT_SYMBOL(empty_zero_page);
> EXPORT_SYMBOL(__copy_tofrom_user);
> EXPORT_SYMBOL(__clear_user);
> EXPORT_SYMBOL(memset);
> diff --git a/arch/openrisc/mm/init.c b/arch/openrisc/mm/init.c
> index 78fb0734cdbc..89d8c6df8855 100644
> --- a/arch/openrisc/mm/init.c
> +++ b/arch/openrisc/mm/init.c
> @@ -188,9 +188,6 @@ void __init mem_init(void)
> {
> BUG_ON(!mem_map);
>
> - /* clear the zero-page */
> - memset((void *)empty_zero_page, 0, PAGE_SIZE);
> -
> printk("mem_init_done ...........................................\n");
> mem_init_done = 1;
> return;
> diff --git a/arch/parisc/include/asm/pgtable.h b/arch/parisc/include/asm/pgtable.h
> index 2c139a4dbf4b..cbdc01a26ea0 100644
> --- a/arch/parisc/include/asm/pgtable.h
> +++ b/arch/parisc/include/asm/pgtable.h
> @@ -262,17 +262,6 @@ extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
>
> extern pte_t pg0[];
>
> -/* zero page used for uninitialized stuff */
> -
> -extern unsigned long *empty_zero_page;
> -
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> #define pte_none(x) (pte_val(x) == 0)
> #define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
> #define pte_user(x) (pte_val(x) & _PAGE_USER)
> diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
> index 6a39e031e5ff..be3380c9bcda 100644
> --- a/arch/parisc/mm/init.c
> +++ b/arch/parisc/mm/init.c
> @@ -604,9 +604,6 @@ void __init mem_init(void)
> #endif
> }
>
> -unsigned long *empty_zero_page __ro_after_init;
> -EXPORT_SYMBOL(empty_zero_page);
> -
> /*
> * pagetable_init() sets up the page tables
> *
> @@ -639,9 +636,6 @@ static void __init pagetable_init(void)
> initrd_end - initrd_start, PAGE_KERNEL, 0);
> }
> #endif
> -
> - empty_zero_page = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
> -
> }
>
> static void __init gateway_init(void)
> diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h
> index dcd3a88caaf6..b27d94c06d0e 100644
> --- a/arch/powerpc/include/asm/pgtable.h
> +++ b/arch/powerpc/include/asm/pgtable.h
> @@ -76,12 +76,6 @@ static inline const void *pmd_page_vaddr(pmd_t pmd)
> }
> #define pmd_page_vaddr pmd_page_vaddr
> #endif
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -extern unsigned long empty_zero_page[];
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
>
> extern pgd_t swapper_pg_dir[];
>
> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
> index 3789a51bdaae..85508392a6b6 100644
> --- a/arch/powerpc/mm/mem.c
> +++ b/arch/powerpc/mm/mem.c
> @@ -34,9 +34,6 @@
>
> unsigned long long memory_limit __initdata;
>
> -unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
> -EXPORT_SYMBOL(empty_zero_page);
> -
> pgprot_t __phys_mem_access_prot(unsigned long pfn, unsigned long size,
> pgprot_t vma_prot)
> {
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index 9ecbf0366719..a6b496f4944f 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -1258,13 +1258,6 @@ extern u64 satp_mode;
> void paging_init(void);
> void misc_mem_init(void);
>
> -/*
> - * ZERO_PAGE is a global shared page that is always zero,
> - * used for zero-mapped memory areas, etc.
> - */
> -extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> /*
> * Use set_p*_safe(), and elide TLB flushing, when confident that *no*
> * TLB flush will be required as a result of the "set". For example, use
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 848efeb9e163..95ac79c62067 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -69,10 +69,6 @@ unsigned long vmemmap_start_pfn __ro_after_init;
> EXPORT_SYMBOL(vmemmap_start_pfn);
> #endif
>
> -unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
> - __page_aligned_bss;
> -EXPORT_SYMBOL(empty_zero_page);
> -
> extern char _start[];
> void *_dtb_early_va __initdata;
> uintptr_t _dtb_early_pa __initdata;
> diff --git a/arch/sh/include/asm/pgtable.h b/arch/sh/include/asm/pgtable.h
> index 10fa8f2bb8d1..d5ce0950a323 100644
> --- a/arch/sh/include/asm/pgtable.h
> +++ b/arch/sh/include/asm/pgtable.h
> @@ -20,14 +20,6 @@
> #ifndef __ASSEMBLER__
> #include <asm/addrspace.h>
> #include <asm/fixmap.h>
> -
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> #endif /* !__ASSEMBLER__ */
>
> /*
> diff --git a/arch/sh/include/asm/setup.h b/arch/sh/include/asm/setup.h
> index 84bb23a771f3..63c9efc06348 100644
> --- a/arch/sh/include/asm/setup.h
> +++ b/arch/sh/include/asm/setup.h
> @@ -7,7 +7,8 @@
> /*
> * This is set up by the setup-routine at boot-time
> */
> -#define PARAM ((unsigned char *)empty_zero_page)
> +extern unsigned char *boot_params_page;
> +#define PARAM boot_params_page
>
> #define MOUNT_ROOT_RDONLY (*(unsigned long *) (PARAM+0x000))
> #define RAMDISK_FLAGS (*(unsigned long *) (PARAM+0x004))
> diff --git a/arch/sh/kernel/head_32.S b/arch/sh/kernel/head_32.S
> index b603b7968b38..0b91bb85d40a 100644
> --- a/arch/sh/kernel/head_32.S
> +++ b/arch/sh/kernel/head_32.S
> @@ -26,7 +26,7 @@
> #endif
>
> .section .empty_zero_page, "aw"
> -ENTRY(empty_zero_page)
> +ENTRY(boot_params_page)
> .long 1 /* MOUNT_ROOT_RDONLY */
> .long 0 /* RAMDISK_FLAGS */
> .long 0x0200 /* ORIG_ROOT_DEV */
> @@ -39,7 +39,7 @@ ENTRY(empty_zero_page)
> .long 0x53453f00 + 29 /* "SE?" = 29 bit */
> #endif
> 1:
> - .skip PAGE_SIZE - empty_zero_page - 1b
> + .skip PAGE_SIZE - boot_params_page - 1b
>
> __HEAD
>
> diff --git a/arch/sh/kernel/sh_ksyms_32.c b/arch/sh/kernel/sh_ksyms_32.c
> index 5858936cb431..041191002e2e 100644
> --- a/arch/sh/kernel/sh_ksyms_32.c
> +++ b/arch/sh/kernel/sh_ksyms_32.c
> @@ -20,7 +20,6 @@ EXPORT_SYMBOL(csum_partial);
> EXPORT_SYMBOL(csum_partial_copy_generic);
> EXPORT_SYMBOL(copy_page);
> EXPORT_SYMBOL(__clear_user);
> -EXPORT_SYMBOL(empty_zero_page);
> #ifdef CONFIG_FLATMEM
> /* need in pfn_valid macro */
> EXPORT_SYMBOL(min_low_pfn);
> diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
> index 464a3a63e2fa..4e40d5e96be9 100644
> --- a/arch/sh/mm/init.c
> +++ b/arch/sh/mm/init.c
> @@ -332,7 +332,6 @@ void __init mem_init(void)
> cpu_cache_init();
>
> /* clear the zero-page */
> - memset(empty_zero_page, 0, PAGE_SIZE);
> __flush_wback_region(empty_zero_page, PAGE_SIZE);
>
> vsyscall_init();
> diff --git a/arch/sparc/include/asm/pgtable_32.h b/arch/sparc/include/asm/pgtable_32.h
> index a9f802d1dd64..f89b1250661d 100644
> --- a/arch/sparc/include/asm/pgtable_32.h
> +++ b/arch/sparc/include/asm/pgtable_32.h
> @@ -71,14 +71,6 @@ extern unsigned long ptr_in_current_pgd;
> extern unsigned long phys_base;
> extern unsigned long pfn_base;
>
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
> -
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> /*
> * In general all page table modifications should use the V8 atomic
> * swap instruction. This insures the mmu and the cpu are in sync
> diff --git a/arch/sparc/include/asm/setup.h b/arch/sparc/include/asm/setup.h
> index 72205684e51e..21bed5514028 100644
> --- a/arch/sparc/include/asm/setup.h
> +++ b/arch/sparc/include/asm/setup.h
> @@ -17,8 +17,6 @@ extern char reboot_command[];
> */
> extern unsigned char boot_cpu_id;
>
> -extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
> -
> extern int serial_console;
> static inline int con_is_present(void)
> {
> diff --git a/arch/sparc/kernel/head_32.S b/arch/sparc/kernel/head_32.S
> index 38345460d542..8c320fa25a67 100644
> --- a/arch/sparc/kernel/head_32.S
> +++ b/arch/sparc/kernel/head_32.S
> @@ -57,13 +57,6 @@ sun4e_notsup:
>
> .align PAGE_SIZE
>
> -/* This was the only reasonable way I could think of to properly align
> - * these page-table data structures.
> - */
> - .globl empty_zero_page
> -empty_zero_page: .skip PAGE_SIZE
> -EXPORT_SYMBOL(empty_zero_page)
> -
> .global root_flags
> .global ram_flags
> .global root_dev
> diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
> index fdc93dd12c3e..e0e66f91ceeb 100644
> --- a/arch/sparc/mm/init_32.c
> +++ b/arch/sparc/mm/init_32.c
> @@ -246,10 +246,6 @@ void __init arch_mm_preinit(void)
> prom_halt();
> }
>
> -
> - /* Saves us work later. */
> - memset((void *)empty_zero_page, 0, PAGE_SIZE);
> -
> i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
> i += 1;
> sparc_valid_addr_bitmap = (unsigned long *)
> diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
> index 4f7bdb18774b..0cc8de2fea90 100644
> --- a/arch/sparc/mm/init_64.c
> +++ b/arch/sparc/mm/init_64.c
> @@ -2498,6 +2498,9 @@ static void __init register_page_bootmem_info(void)
> }
> void __init mem_init(void)
> {
> + phys_addr_t zero_page_pa = kern_base +
> + ((unsigned long)&empty_zero_page[0] - KERNBASE);
> +
> /*
> * Must be done after boot memory is put on freelist, because here we
> * might set fields in deferred struct pages that have not yet been
> @@ -2510,13 +2513,7 @@ void __init mem_init(void)
> * Set up the zero page, mark it reserved, so that page count
> * is not manipulated when freeing the page from user ptes.
> */
> - mem_map_zero = alloc_pages(GFP_KERNEL|__GFP_ZERO, 0);
> - if (mem_map_zero == NULL) {
> - prom_printf("paging_init: Cannot alloc zero page.\n");
> - prom_halt();
> - }
> - mark_page_reserved(mem_map_zero);
> -
> + mem_map_zero = pfn_to_page(PHYS_PFN(zero_page_pa));
>
> if (tlb_type == cheetah || tlb_type == cheetah_plus)
> cheetah_ecache_flush_init();
> diff --git a/arch/um/include/asm/pgtable.h b/arch/um/include/asm/pgtable.h
> index 3b42b0f45bf6..19e0608fb649 100644
> --- a/arch/um/include/asm/pgtable.h
> +++ b/arch/um/include/asm/pgtable.h
> @@ -34,9 +34,6 @@
>
> extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
>
> -/* zero page used for uninitialized stuff */
> -extern unsigned long *empty_zero_page;
> -
> /* Just any arbitrary offset to the start of the vmalloc VM area: the
> * current 8MB value just means that there will be a 8MB "hole" after the
> * physical memory until the kernel virtual memory starts. That means that
> @@ -74,12 +71,6 @@ extern unsigned long *empty_zero_page;
> * get..
> */
>
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
> -
> #define pte_clear(mm, addr, xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEEDSYNC))
>
> #define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEEDSYNC))
> diff --git a/arch/um/include/shared/kern_util.h b/arch/um/include/shared/kern_util.h
> index 38321188c04c..9812efd14ec0 100644
> --- a/arch/um/include/shared/kern_util.h
> +++ b/arch/um/include/shared/kern_util.h
> @@ -38,7 +38,6 @@ extern void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs
> extern void uml_pm_wake(void);
>
> extern int start_uml(void);
> -extern void paging_init(void);
>
> extern void uml_cleanup(void);
> extern void do_uml_exitcalls(void);
> diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
> index 89c8c8b94a79..1eef0e42ef5d 100644
> --- a/arch/um/kernel/mem.c
> +++ b/arch/um/kernel/mem.c
> @@ -44,10 +44,6 @@ __section(".kasan_init") __used
> = kasan_init;
> #endif
>
> -/* allocated in paging_init, zeroed in mem_init, and unchanged thereafter */
> -unsigned long *empty_zero_page = NULL;
> -EXPORT_SYMBOL(empty_zero_page);
> -
> /*
> * Initialized during boot, and readonly for initializing page tables
> * afterwards
> @@ -65,9 +61,6 @@ void __init arch_mm_preinit(void)
> /* Safe to call after jump_label_init(). Enables KASAN. */
> kasan_init_generic();
>
> - /* clear the zero-page */
> - memset(empty_zero_page, 0, PAGE_SIZE);
> -
> /* Map in the area just after the brk now that kmalloc is about
> * to be turned on.
> */
> @@ -89,15 +82,6 @@ void __init arch_zone_limits_init(unsigned long *max_zone_pfns)
> max_zone_pfns[ZONE_NORMAL] = high_physmem >> PAGE_SHIFT;
> }
>
> -void __init paging_init(void)
> -{
> - empty_zero_page = (unsigned long *) memblock_alloc_low(PAGE_SIZE,
> - PAGE_SIZE);
> - if (!empty_zero_page)
> - panic("%s: Failed to allocate %lu bytes align=%lx\n",
> - __func__, PAGE_SIZE, PAGE_SIZE);
> -}
> -
> /*
> * This can't do anything because nothing in the kernel image can be freed
> * since it's not in kernel physical memory.
> diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
> index e2b24e1ecfa6..2141f5f1f5a2 100644
> --- a/arch/um/kernel/um_arch.c
> +++ b/arch/um/kernel/um_arch.c
> @@ -413,7 +413,6 @@ void __init setup_arch(char **cmdline_p)
> uml_dtb_init();
> read_initrd();
>
> - paging_init();
> strscpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
> *cmdline_p = command_line;
> setup_hostinfo(host_info, sizeof host_info);
> diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
> index 1662c5a8f445..54289f4587a4 100644
> --- a/arch/x86/include/asm/pgtable.h
> +++ b/arch/x86/include/asm/pgtable.h
> @@ -47,14 +47,6 @@ void ptdump_walk_user_pgd_level_checkwx(void);
> #define debug_checkwx_user() do { } while (0)
> #endif
>
> -/*
> - * ZERO_PAGE is a global shared page that is always zero: used
> - * for zero-mapped memory areas etc..
> - */
> -extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
> - __visible;
> -#define ZERO_PAGE(vaddr) ((void)(vaddr),virt_to_page(empty_zero_page))
> -
> extern spinlock_t pgd_lock;
> extern struct list_head pgd_list;
>
> diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
> index 80ef5d386b03..5171cb746444 100644
> --- a/arch/x86/kernel/head_32.S
> +++ b/arch/x86/kernel/head_32.S
> @@ -441,10 +441,6 @@ initial_pg_fixmap:
> swapper_pg_dir:
> .fill 1024,4,0
> .fill PTI_USER_PGD_FILL,4,0
> -.globl empty_zero_page
> -empty_zero_page:
> - .fill 4096,1,0
> -EXPORT_SYMBOL(empty_zero_page)
>
> /*
> * This starts the data section.
> diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
> index 21816b48537c..cbf7647a25d8 100644
> --- a/arch/x86/kernel/head_64.S
> +++ b/arch/x86/kernel/head_64.S
> @@ -712,10 +712,3 @@ SYM_PIC_ALIAS(phys_base);
> EXPORT_SYMBOL(phys_base)
>
> #include "../xen/xen-head.S"
> -
> - __PAGE_ALIGNED_BSS
> -SYM_DATA_START_PAGE_ALIGNED(empty_zero_page)
> - .skip PAGE_SIZE
> -SYM_DATA_END(empty_zero_page)
> -EXPORT_SYMBOL(empty_zero_page)
> -
> diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h
> index 50a136213b2b..61f07d981a94 100644
> --- a/arch/xtensa/include/asm/pgtable.h
> +++ b/arch/xtensa/include/asm/pgtable.h
> @@ -209,10 +209,6 @@
> #define pgd_ERROR(e) \
> printk("%s:%d: bad pgd entry %08lx.\n", __FILE__, __LINE__, pgd_val(e))
>
> -extern unsigned long empty_zero_page[1024];
> -
> -#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> -
> #ifdef CONFIG_MMU
> extern pgd_t swapper_pg_dir[PAGE_SIZE/sizeof(pgd_t)];
> extern void paging_init(void);
> diff --git a/arch/xtensa/kernel/head.S b/arch/xtensa/kernel/head.S
> index 8484294bc623..4b0c5c5e685a 100644
> --- a/arch/xtensa/kernel/head.S
> +++ b/arch/xtensa/kernel/head.S
> @@ -381,6 +381,3 @@ ENTRY(swapper_pg_dir)
> .fill PAGE_SIZE, 1, 0
> END(swapper_pg_dir)
> #endif
> -ENTRY(empty_zero_page)
> - .fill PAGE_SIZE, 1, 0
> -END(empty_zero_page)
> diff --git a/arch/xtensa/kernel/xtensa_ksyms.c b/arch/xtensa/kernel/xtensa_ksyms.c
> index 62d81e76e18e..ced335b4df5f 100644
> --- a/arch/xtensa/kernel/xtensa_ksyms.c
> +++ b/arch/xtensa/kernel/xtensa_ksyms.c
> @@ -15,8 +15,6 @@
> #include <linux/module.h>
> #include <asm/pgtable.h>
>
> -EXPORT_SYMBOL(empty_zero_page);
> -
> unsigned int __sync_fetch_and_and_4(volatile void *p, unsigned int v)
> {
> BUG();
> diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
> index 9bacf4df9769..3d48eea57cd2 100644
> --- a/include/linux/pgtable.h
> +++ b/include/linux/pgtable.h
> @@ -1890,6 +1890,9 @@ static inline void pfnmap_setup_cachemode_pfn(unsigned long pfn, pgprot_t *prot)
> * for different ranges in the virtual address space.
> *
> * zero_page_pfn identifies the first (or the only) pfn for these pages.
> + *
> + * For architectures that don't __HAVE_COLOR_ZERO_PAGE the zero page lives in
> + * empty_zero_page in BSS.
> */
> #ifdef __HAVE_COLOR_ZERO_PAGE
> static inline int is_zero_pfn(unsigned long pfn)
> @@ -1916,6 +1919,13 @@ static inline unsigned long zero_pfn(unsigned long addr)
>
> return zero_page_pfn;
> }
> +
> +extern uint8_t empty_zero_page[PAGE_SIZE];
> +
> +#ifndef ZERO_PAGE
> +#define ZERO_PAGE(vaddr) ((void)(vaddr),virt_to_page(empty_zero_page))
> +#endif
> +
> #endif /* __HAVE_COLOR_ZERO_PAGE */
>
> #ifdef CONFIG_MMU
> diff --git a/mm/mm_init.c b/mm/mm_init.c
> index a0ca236eb4f5..1eac634ece1a 100644
> --- a/mm/mm_init.c
> +++ b/mm/mm_init.c
> @@ -56,6 +56,11 @@ EXPORT_SYMBOL(high_memory);
> unsigned long zero_page_pfn __ro_after_init;
> EXPORT_SYMBOL(zero_page_pfn);
>
> +#ifndef __HAVE_COLOR_ZERO_PAGE
> +uint8_t empty_zero_page[PAGE_SIZE] __page_aligned_bss;
> +EXPORT_SYMBOL(empty_zero_page);
> +#endif
> +
> #ifdef CONFIG_DEBUG_MEMORY_INIT
> int __meminitdata mminit_loglevel;
>
> --
> 2.51.0