| // SPDX-License-Identifier: GPL-2.0-only | |
| /* | |
| * This kernel test validates architecture page table helpers and | |
| * accessors and helps in verifying their continued compliance with | |
| * expected generic MM semantics. | |
| * | |
| * Copyright (C) 2019 ARM Ltd. | |
| * | |
| * Author: Anshuman Khandual <anshuman.khandual@arm.com> | |
| */ | |
| #define pr_fmt(fmt) "debug_vm_pgtable: [%-25s]: " fmt, __func__ | |
| #include <linux/gfp.h> | |
| #include <linux/highmem.h> | |
| #include <linux/hugetlb.h> | |
| #include <linux/kernel.h> | |
| #include <linux/kconfig.h> | |
| #include <linux/memblock.h> | |
| #include <linux/mm.h> | |
| #include <linux/mman.h> | |
| #include <linux/mm_types.h> | |
| #include <linux/module.h> | |
| #include <linux/pfn_t.h> | |
| #include <linux/printk.h> | |
| #include <linux/pgtable.h> | |
| #include <linux/random.h> | |
| #include <linux/spinlock.h> | |
| #include <linux/swap.h> | |
| #include <linux/swapops.h> | |
| #include <linux/start_kernel.h> | |
| #include <linux/sched/mm.h> | |
| #include <linux/io.h> | |
| #include <linux/vmalloc.h> | |
| #include <asm/cacheflush.h> | |
| #include <asm/pgalloc.h> | |
| #include <asm/tlbflush.h> | |
| /* | |
| * Please refer Documentation/mm/arch_pgtable_helpers.rst for the semantics | |
| * expectations that are being validated here. All future changes in here | |
| * or the documentation need to be in sync. | |
| */ | |
| #define RANDOM_NZVALUE GENMASK(7, 0) | |
| struct pgtable_debug_args { | |
| struct mm_struct *mm; | |
| struct vm_area_struct *vma; | |
| pgd_t *pgdp; | |
| p4d_t *p4dp; | |
| pud_t *pudp; | |
| pmd_t *pmdp; | |
| pte_t *ptep; | |
| p4d_t *start_p4dp; | |
| pud_t *start_pudp; | |
| pmd_t *start_pmdp; | |
| pgtable_t start_ptep; | |
| unsigned long vaddr; | |
| pgprot_t page_prot; | |
| pgprot_t page_prot_none; | |
| bool is_contiguous_page; | |
| unsigned long pud_pfn; | |
| unsigned long pmd_pfn; | |
| unsigned long pte_pfn; | |
| unsigned long fixed_alignment; | |
| unsigned long fixed_pgd_pfn; | |
| unsigned long fixed_p4d_pfn; | |
| unsigned long fixed_pud_pfn; | |
| unsigned long fixed_pmd_pfn; | |
| unsigned long fixed_pte_pfn; | |
| }; | |
| static void __init pte_basic_tests(struct pgtable_debug_args *args, int idx) | |
| { | |
| pgprot_t prot = vm_get_page_prot(idx); | |
| pte_t pte = pfn_pte(args->fixed_pte_pfn, prot); | |
| unsigned long val = idx, *ptr = &val; | |
| pr_debug("Validating PTE basic (%pGv)\n", ptr); | |
| /* | |
| * This test needs to be executed after the given page table entry | |
| * is created with pfn_pte() to make sure that vm_get_page_prot(idx) | |
| * does not have the dirty bit enabled from the beginning. This is | |
| * important for platforms like arm64 where (!PTE_RDONLY) indicate | |
| * dirty bit being set. | |
| */ | |
| WARN_ON(pte_dirty(pte_wrprotect(pte))); | |
| WARN_ON(!pte_same(pte, pte)); | |
| WARN_ON(!pte_young(pte_mkyoung(pte_mkold(pte)))); | |
| WARN_ON(!pte_dirty(pte_mkdirty(pte_mkclean(pte)))); | |
| WARN_ON(!pte_write(pte_mkwrite(pte_wrprotect(pte), args->vma))); | |
| WARN_ON(pte_young(pte_mkold(pte_mkyoung(pte)))); | |
| WARN_ON(pte_dirty(pte_mkclean(pte_mkdirty(pte)))); | |
| WARN_ON(pte_write(pte_wrprotect(pte_mkwrite(pte, args->vma)))); | |
| WARN_ON(pte_dirty(pte_wrprotect(pte_mkclean(pte)))); | |
| WARN_ON(!pte_dirty(pte_wrprotect(pte_mkdirty(pte)))); | |
| } | |
| static void __init pte_advanced_tests(struct pgtable_debug_args *args) | |
| { | |
| struct page *page; | |
| pte_t pte; | |
| /* | |
| * Architectures optimize set_pte_at by avoiding TLB flush. | |
| * This requires set_pte_at to be not used to update an | |
| * existing pte entry. Clear pte before we do set_pte_at | |
| * | |
| * flush_dcache_page() is called after set_pte_at() to clear | |
| * PG_arch_1 for the page on ARM64. The page flag isn't cleared | |
| * when it's released and page allocation check will fail when | |
| * the page is allocated again. For architectures other than ARM64, | |
| * the unexpected overhead of cache flushing is acceptable. | |
| */ | |
| page = (args->pte_pfn != ULONG_MAX) ? pfn_to_page(args->pte_pfn) : NULL; | |
| if (!page) | |
| return; | |
| pr_debug("Validating PTE advanced\n"); | |
| if (WARN_ON(!args->ptep)) | |
| return; | |
| pte = pfn_pte(args->pte_pfn, args->page_prot); | |
| set_pte_at(args->mm, args->vaddr, args->ptep, pte); | |
| flush_dcache_page(page); | |
| ptep_set_wrprotect(args->mm, args->vaddr, args->ptep); | |
| pte = ptep_get(args->ptep); | |
| WARN_ON(pte_write(pte)); | |
| ptep_get_and_clear(args->mm, args->vaddr, args->ptep); | |
| pte = ptep_get(args->ptep); | |
| WARN_ON(!pte_none(pte)); | |
| pte = pfn_pte(args->pte_pfn, args->page_prot); | |
| pte = pte_wrprotect(pte); | |
| pte = pte_mkclean(pte); | |
| set_pte_at(args->mm, args->vaddr, args->ptep, pte); | |
| flush_dcache_page(page); | |
| pte = pte_mkwrite(pte, args->vma); | |
| pte = pte_mkdirty(pte); | |
| ptep_set_access_flags(args->vma, args->vaddr, args->ptep, pte, 1); | |
| pte = ptep_get(args->ptep); | |
| WARN_ON(!(pte_write(pte) && pte_dirty(pte))); | |
| ptep_get_and_clear_full(args->mm, args->vaddr, args->ptep, 1); | |
| pte = ptep_get(args->ptep); | |
| WARN_ON(!pte_none(pte)); | |
| pte = pfn_pte(args->pte_pfn, args->page_prot); | |
| pte = pte_mkyoung(pte); | |
| set_pte_at(args->mm, args->vaddr, args->ptep, pte); | |
| flush_dcache_page(page); | |
| ptep_test_and_clear_young(args->vma, args->vaddr, args->ptep); | |
| pte = ptep_get(args->ptep); | |
| WARN_ON(pte_young(pte)); | |
| ptep_get_and_clear_full(args->mm, args->vaddr, args->ptep, 1); | |
| } | |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
| static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx) | |
| { | |
| pgprot_t prot = vm_get_page_prot(idx); | |
| unsigned long val = idx, *ptr = &val; | |
| pmd_t pmd; | |
| if (!has_transparent_hugepage()) | |
| return; | |
| pr_debug("Validating PMD basic (%pGv)\n", ptr); | |
| pmd = pfn_pmd(args->fixed_pmd_pfn, prot); | |
| /* | |
| * This test needs to be executed after the given page table entry | |
| * is created with pfn_pmd() to make sure that vm_get_page_prot(idx) | |
| * does not have the dirty bit enabled from the beginning. This is | |
| * important for platforms like arm64 where (!PTE_RDONLY) indicate | |
| * dirty bit being set. | |
| */ | |
| WARN_ON(pmd_dirty(pmd_wrprotect(pmd))); | |
| WARN_ON(!pmd_same(pmd, pmd)); | |
| WARN_ON(!pmd_young(pmd_mkyoung(pmd_mkold(pmd)))); | |
| WARN_ON(!pmd_dirty(pmd_mkdirty(pmd_mkclean(pmd)))); | |
| WARN_ON(!pmd_write(pmd_mkwrite(pmd_wrprotect(pmd), args->vma))); | |
| WARN_ON(pmd_young(pmd_mkold(pmd_mkyoung(pmd)))); | |
| WARN_ON(pmd_dirty(pmd_mkclean(pmd_mkdirty(pmd)))); | |
| WARN_ON(pmd_write(pmd_wrprotect(pmd_mkwrite(pmd, args->vma)))); | |
| WARN_ON(pmd_dirty(pmd_wrprotect(pmd_mkclean(pmd)))); | |
| WARN_ON(!pmd_dirty(pmd_wrprotect(pmd_mkdirty(pmd)))); | |
| /* | |
| * A huge page does not point to next level page table | |
| * entry. Hence this must qualify as pmd_bad(). | |
| */ | |
| WARN_ON(!pmd_bad(pmd_mkhuge(pmd))); | |
| } | |
| static void __init pmd_advanced_tests(struct pgtable_debug_args *args) | |
| { | |
| struct page *page; | |
| pmd_t pmd; | |
| unsigned long vaddr = args->vaddr; | |
| if (!has_transparent_hugepage()) | |
| return; | |
| page = (args->pmd_pfn != ULONG_MAX) ? pfn_to_page(args->pmd_pfn) : NULL; | |
| if (!page) | |
| return; | |
| /* | |
| * flush_dcache_page() is called after set_pmd_at() to clear | |
| * PG_arch_1 for the page on ARM64. The page flag isn't cleared | |
| * when it's released and page allocation check will fail when | |
| * the page is allocated again. For architectures other than ARM64, | |
| * the unexpected overhead of cache flushing is acceptable. | |
| */ | |
| pr_debug("Validating PMD advanced\n"); | |
| /* Align the address wrt HPAGE_PMD_SIZE */ | |
| vaddr &= HPAGE_PMD_MASK; | |
| pgtable_trans_huge_deposit(args->mm, args->pmdp, args->start_ptep); | |
| pmd = pfn_pmd(args->pmd_pfn, args->page_prot); | |
| set_pmd_at(args->mm, vaddr, args->pmdp, pmd); | |
| flush_dcache_page(page); | |
| pmdp_set_wrprotect(args->mm, vaddr, args->pmdp); | |
| pmd = pmdp_get(args->pmdp); | |
| WARN_ON(pmd_write(pmd)); | |
| pmdp_huge_get_and_clear(args->mm, vaddr, args->pmdp); | |
| pmd = pmdp_get(args->pmdp); | |
| WARN_ON(!pmd_none(pmd)); | |
| pmd = pfn_pmd(args->pmd_pfn, args->page_prot); | |
| pmd = pmd_wrprotect(pmd); | |
| pmd = pmd_mkclean(pmd); | |
| set_pmd_at(args->mm, vaddr, args->pmdp, pmd); | |
| flush_dcache_page(page); | |
| pmd = pmd_mkwrite(pmd, args->vma); | |
| pmd = pmd_mkdirty(pmd); | |
| pmdp_set_access_flags(args->vma, vaddr, args->pmdp, pmd, 1); | |
| pmd = pmdp_get(args->pmdp); | |
| WARN_ON(!(pmd_write(pmd) && pmd_dirty(pmd))); | |
| pmdp_huge_get_and_clear_full(args->vma, vaddr, args->pmdp, 1); | |
| pmd = pmdp_get(args->pmdp); | |
| WARN_ON(!pmd_none(pmd)); | |
| pmd = pmd_mkhuge(pfn_pmd(args->pmd_pfn, args->page_prot)); | |
| pmd = pmd_mkyoung(pmd); | |
| set_pmd_at(args->mm, vaddr, args->pmdp, pmd); | |
| flush_dcache_page(page); | |
| pmdp_test_and_clear_young(args->vma, vaddr, args->pmdp); | |
| pmd = pmdp_get(args->pmdp); | |
| WARN_ON(pmd_young(pmd)); | |
| /* Clear the pte entries */ | |
| pmdp_huge_get_and_clear(args->mm, vaddr, args->pmdp); | |
| pgtable_trans_huge_withdraw(args->mm, args->pmdp); | |
| } | |
| static void __init pmd_leaf_tests(struct pgtable_debug_args *args) | |
| { | |
| pmd_t pmd; | |
| if (!has_transparent_hugepage()) | |
| return; | |
| pr_debug("Validating PMD leaf\n"); | |
| pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot); | |
| /* | |
| * PMD based THP is a leaf entry. | |
| */ | |
| pmd = pmd_mkhuge(pmd); | |
| WARN_ON(!pmd_leaf(pmd)); | |
| } | |
| #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD | |
| static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) | |
| { | |
| pgprot_t prot = vm_get_page_prot(idx); | |
| unsigned long val = idx, *ptr = &val; | |
| pud_t pud; | |
| if (!has_transparent_pud_hugepage()) | |
| return; | |
| pr_debug("Validating PUD basic (%pGv)\n", ptr); | |
| pud = pfn_pud(args->fixed_pud_pfn, prot); | |
| /* | |
| * This test needs to be executed after the given page table entry | |
| * is created with pfn_pud() to make sure that vm_get_page_prot(idx) | |
| * does not have the dirty bit enabled from the beginning. This is | |
| * important for platforms like arm64 where (!PTE_RDONLY) indicate | |
| * dirty bit being set. | |
| */ | |
| WARN_ON(pud_dirty(pud_wrprotect(pud))); | |
| WARN_ON(!pud_same(pud, pud)); | |
| WARN_ON(!pud_young(pud_mkyoung(pud_mkold(pud)))); | |
| WARN_ON(!pud_dirty(pud_mkdirty(pud_mkclean(pud)))); | |
| WARN_ON(pud_dirty(pud_mkclean(pud_mkdirty(pud)))); | |
| WARN_ON(!pud_write(pud_mkwrite(pud_wrprotect(pud)))); | |
| WARN_ON(pud_write(pud_wrprotect(pud_mkwrite(pud)))); | |
| WARN_ON(pud_young(pud_mkold(pud_mkyoung(pud)))); | |
| WARN_ON(pud_dirty(pud_wrprotect(pud_mkclean(pud)))); | |
| WARN_ON(!pud_dirty(pud_wrprotect(pud_mkdirty(pud)))); | |
| if (mm_pmd_folded(args->mm)) | |
| return; | |
| /* | |
| * A huge page does not point to next level page table | |
| * entry. Hence this must qualify as pud_bad(). | |
| */ | |
| WARN_ON(!pud_bad(pud_mkhuge(pud))); | |
| } | |
| static void __init pud_advanced_tests(struct pgtable_debug_args *args) | |
| { | |
| struct page *page; | |
| unsigned long vaddr = args->vaddr; | |
| pud_t pud; | |
| if (!has_transparent_pud_hugepage()) | |
| return; | |
| page = (args->pud_pfn != ULONG_MAX) ? pfn_to_page(args->pud_pfn) : NULL; | |
| if (!page) | |
| return; | |
| /* | |
| * flush_dcache_page() is called after set_pud_at() to clear | |
| * PG_arch_1 for the page on ARM64. The page flag isn't cleared | |
| * when it's released and page allocation check will fail when | |
| * the page is allocated again. For architectures other than ARM64, | |
| * the unexpected overhead of cache flushing is acceptable. | |
| */ | |
| pr_debug("Validating PUD advanced\n"); | |
| /* Align the address wrt HPAGE_PUD_SIZE */ | |
| vaddr &= HPAGE_PUD_MASK; | |
| pud = pfn_pud(args->pud_pfn, args->page_prot); | |
| /* | |
| * Some architectures have debug checks to make sure | |
| * huge pud mapping are only found with devmap entries | |
| * For now test with only devmap entries. | |
| */ | |
| pud = pud_mkdevmap(pud); | |
| set_pud_at(args->mm, vaddr, args->pudp, pud); | |
| flush_dcache_page(page); | |
| pudp_set_wrprotect(args->mm, vaddr, args->pudp); | |
| pud = pudp_get(args->pudp); | |
| WARN_ON(pud_write(pud)); | |
| #ifndef __PAGETABLE_PMD_FOLDED | |
| pudp_huge_get_and_clear(args->mm, vaddr, args->pudp); | |
| pud = pudp_get(args->pudp); | |
| WARN_ON(!pud_none(pud)); | |
| #endif /* __PAGETABLE_PMD_FOLDED */ | |
| pud = pfn_pud(args->pud_pfn, args->page_prot); | |
| pud = pud_mkdevmap(pud); | |
| pud = pud_wrprotect(pud); | |
| pud = pud_mkclean(pud); | |
| set_pud_at(args->mm, vaddr, args->pudp, pud); | |
| flush_dcache_page(page); | |
| pud = pud_mkwrite(pud); | |
| pud = pud_mkdirty(pud); | |
| pudp_set_access_flags(args->vma, vaddr, args->pudp, pud, 1); | |
| pud = pudp_get(args->pudp); | |
| WARN_ON(!(pud_write(pud) && pud_dirty(pud))); | |
| #ifndef __PAGETABLE_PMD_FOLDED | |
| pudp_huge_get_and_clear_full(args->vma, vaddr, args->pudp, 1); | |
| pud = pudp_get(args->pudp); | |
| WARN_ON(!pud_none(pud)); | |
| #endif /* __PAGETABLE_PMD_FOLDED */ | |
| pud = pfn_pud(args->pud_pfn, args->page_prot); | |
| pud = pud_mkdevmap(pud); | |
| pud = pud_mkyoung(pud); | |
| set_pud_at(args->mm, vaddr, args->pudp, pud); | |
| flush_dcache_page(page); | |
| pudp_test_and_clear_young(args->vma, vaddr, args->pudp); | |
| pud = pudp_get(args->pudp); | |
| WARN_ON(pud_young(pud)); | |
| pudp_huge_get_and_clear(args->mm, vaddr, args->pudp); | |
| } | |
| static void __init pud_leaf_tests(struct pgtable_debug_args *args) | |
| { | |
| pud_t pud; | |
| if (!has_transparent_pud_hugepage()) | |
| return; | |
| pr_debug("Validating PUD leaf\n"); | |
| pud = pfn_pud(args->fixed_pud_pfn, args->page_prot); | |
| /* | |
| * PUD based THP is a leaf entry. | |
| */ | |
| pud = pud_mkhuge(pud); | |
| WARN_ON(!pud_leaf(pud)); | |
| } | |
| #else /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ | |
| static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) { } | |
| static void __init pud_advanced_tests(struct pgtable_debug_args *args) { } | |
| static void __init pud_leaf_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ | |
| #else /* !CONFIG_TRANSPARENT_HUGEPAGE */ | |
| static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx) { } | |
| static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) { } | |
| static void __init pmd_advanced_tests(struct pgtable_debug_args *args) { } | |
| static void __init pud_advanced_tests(struct pgtable_debug_args *args) { } | |
| static void __init pmd_leaf_tests(struct pgtable_debug_args *args) { } | |
| static void __init pud_leaf_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ | |
| #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP | |
| static void __init pmd_huge_tests(struct pgtable_debug_args *args) | |
| { | |
| pmd_t pmd; | |
| if (!arch_vmap_pmd_supported(args->page_prot) || | |
| args->fixed_alignment < PMD_SIZE) | |
| return; | |
| pr_debug("Validating PMD huge\n"); | |
| /* | |
| * X86 defined pmd_set_huge() verifies that the given | |
| * PMD is not a populated non-leaf entry. | |
| */ | |
| WRITE_ONCE(*args->pmdp, __pmd(0)); | |
| WARN_ON(!pmd_set_huge(args->pmdp, __pfn_to_phys(args->fixed_pmd_pfn), args->page_prot)); | |
| WARN_ON(!pmd_clear_huge(args->pmdp)); | |
| pmd = pmdp_get(args->pmdp); | |
| WARN_ON(!pmd_none(pmd)); | |
| } | |
| static void __init pud_huge_tests(struct pgtable_debug_args *args) | |
| { | |
| pud_t pud; | |
| if (!arch_vmap_pud_supported(args->page_prot) || | |
| args->fixed_alignment < PUD_SIZE) | |
| return; | |
| pr_debug("Validating PUD huge\n"); | |
| /* | |
| * X86 defined pud_set_huge() verifies that the given | |
| * PUD is not a populated non-leaf entry. | |
| */ | |
| WRITE_ONCE(*args->pudp, __pud(0)); | |
| WARN_ON(!pud_set_huge(args->pudp, __pfn_to_phys(args->fixed_pud_pfn), args->page_prot)); | |
| WARN_ON(!pud_clear_huge(args->pudp)); | |
| pud = pudp_get(args->pudp); | |
| WARN_ON(!pud_none(pud)); | |
| } | |
| #else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */ | |
| static void __init pmd_huge_tests(struct pgtable_debug_args *args) { } | |
| static void __init pud_huge_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */ | |
| static void __init p4d_basic_tests(struct pgtable_debug_args *args) | |
| { | |
| p4d_t p4d; | |
| pr_debug("Validating P4D basic\n"); | |
| memset(&p4d, RANDOM_NZVALUE, sizeof(p4d_t)); | |
| WARN_ON(!p4d_same(p4d, p4d)); | |
| } | |
| static void __init pgd_basic_tests(struct pgtable_debug_args *args) | |
| { | |
| pgd_t pgd; | |
| pr_debug("Validating PGD basic\n"); | |
| memset(&pgd, RANDOM_NZVALUE, sizeof(pgd_t)); | |
| WARN_ON(!pgd_same(pgd, pgd)); | |
| } | |
| #ifndef __PAGETABLE_PUD_FOLDED | |
| static void __init pud_clear_tests(struct pgtable_debug_args *args) | |
| { | |
| pud_t pud = pudp_get(args->pudp); | |
| if (mm_pmd_folded(args->mm)) | |
| return; | |
| pr_debug("Validating PUD clear\n"); | |
| WARN_ON(pud_none(pud)); | |
| pud_clear(args->pudp); | |
| pud = pudp_get(args->pudp); | |
| WARN_ON(!pud_none(pud)); | |
| } | |
| static void __init pud_populate_tests(struct pgtable_debug_args *args) | |
| { | |
| pud_t pud; | |
| if (mm_pmd_folded(args->mm)) | |
| return; | |
| pr_debug("Validating PUD populate\n"); | |
| /* | |
| * This entry points to next level page table page. | |
| * Hence this must not qualify as pud_bad(). | |
| */ | |
| pud_populate(args->mm, args->pudp, args->start_pmdp); | |
| pud = pudp_get(args->pudp); | |
| WARN_ON(pud_bad(pud)); | |
| } | |
| #else /* !__PAGETABLE_PUD_FOLDED */ | |
| static void __init pud_clear_tests(struct pgtable_debug_args *args) { } | |
| static void __init pud_populate_tests(struct pgtable_debug_args *args) { } | |
| #endif /* PAGETABLE_PUD_FOLDED */ | |
| #ifndef __PAGETABLE_P4D_FOLDED | |
| static void __init p4d_clear_tests(struct pgtable_debug_args *args) | |
| { | |
| p4d_t p4d = p4dp_get(args->p4dp); | |
| if (mm_pud_folded(args->mm)) | |
| return; | |
| pr_debug("Validating P4D clear\n"); | |
| WARN_ON(p4d_none(p4d)); | |
| p4d_clear(args->p4dp); | |
| p4d = p4dp_get(args->p4dp); | |
| WARN_ON(!p4d_none(p4d)); | |
| } | |
| static void __init p4d_populate_tests(struct pgtable_debug_args *args) | |
| { | |
| p4d_t p4d; | |
| if (mm_pud_folded(args->mm)) | |
| return; | |
| pr_debug("Validating P4D populate\n"); | |
| /* | |
| * This entry points to next level page table page. | |
| * Hence this must not qualify as p4d_bad(). | |
| */ | |
| pud_clear(args->pudp); | |
| p4d_clear(args->p4dp); | |
| p4d_populate(args->mm, args->p4dp, args->start_pudp); | |
| p4d = p4dp_get(args->p4dp); | |
| WARN_ON(p4d_bad(p4d)); | |
| } | |
| static void __init pgd_clear_tests(struct pgtable_debug_args *args) | |
| { | |
| pgd_t pgd = pgdp_get(args->pgdp); | |
| if (mm_p4d_folded(args->mm)) | |
| return; | |
| pr_debug("Validating PGD clear\n"); | |
| WARN_ON(pgd_none(pgd)); | |
| pgd_clear(args->pgdp); | |
| pgd = pgdp_get(args->pgdp); | |
| WARN_ON(!pgd_none(pgd)); | |
| } | |
| static void __init pgd_populate_tests(struct pgtable_debug_args *args) | |
| { | |
| pgd_t pgd; | |
| if (mm_p4d_folded(args->mm)) | |
| return; | |
| pr_debug("Validating PGD populate\n"); | |
| /* | |
| * This entry points to next level page table page. | |
| * Hence this must not qualify as pgd_bad(). | |
| */ | |
| p4d_clear(args->p4dp); | |
| pgd_clear(args->pgdp); | |
| pgd_populate(args->mm, args->pgdp, args->start_p4dp); | |
| pgd = pgdp_get(args->pgdp); | |
| WARN_ON(pgd_bad(pgd)); | |
| } | |
| #else /* !__PAGETABLE_P4D_FOLDED */ | |
| static void __init p4d_clear_tests(struct pgtable_debug_args *args) { } | |
| static void __init pgd_clear_tests(struct pgtable_debug_args *args) { } | |
| static void __init p4d_populate_tests(struct pgtable_debug_args *args) { } | |
| static void __init pgd_populate_tests(struct pgtable_debug_args *args) { } | |
| #endif /* PAGETABLE_P4D_FOLDED */ | |
| static void __init pte_clear_tests(struct pgtable_debug_args *args) | |
| { | |
| struct page *page; | |
| pte_t pte = pfn_pte(args->pte_pfn, args->page_prot); | |
| page = (args->pte_pfn != ULONG_MAX) ? pfn_to_page(args->pte_pfn) : NULL; | |
| if (!page) | |
| return; | |
| /* | |
| * flush_dcache_page() is called after set_pte_at() to clear | |
| * PG_arch_1 for the page on ARM64. The page flag isn't cleared | |
| * when it's released and page allocation check will fail when | |
| * the page is allocated again. For architectures other than ARM64, | |
| * the unexpected overhead of cache flushing is acceptable. | |
| */ | |
| pr_debug("Validating PTE clear\n"); | |
| if (WARN_ON(!args->ptep)) | |
| return; | |
| set_pte_at(args->mm, args->vaddr, args->ptep, pte); | |
| WARN_ON(pte_none(pte)); | |
| flush_dcache_page(page); | |
| barrier(); | |
| ptep_clear(args->mm, args->vaddr, args->ptep); | |
| pte = ptep_get(args->ptep); | |
| WARN_ON(!pte_none(pte)); | |
| } | |
| static void __init pmd_clear_tests(struct pgtable_debug_args *args) | |
| { | |
| pmd_t pmd = pmdp_get(args->pmdp); | |
| pr_debug("Validating PMD clear\n"); | |
| WARN_ON(pmd_none(pmd)); | |
| pmd_clear(args->pmdp); | |
| pmd = pmdp_get(args->pmdp); | |
| WARN_ON(!pmd_none(pmd)); | |
| } | |
| static void __init pmd_populate_tests(struct pgtable_debug_args *args) | |
| { | |
| pmd_t pmd; | |
| pr_debug("Validating PMD populate\n"); | |
| /* | |
| * This entry points to next level page table page. | |
| * Hence this must not qualify as pmd_bad(). | |
| */ | |
| pmd_populate(args->mm, args->pmdp, args->start_ptep); | |
| pmd = pmdp_get(args->pmdp); | |
| WARN_ON(pmd_bad(pmd)); | |
| } | |
| static void __init pte_special_tests(struct pgtable_debug_args *args) | |
| { | |
| pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot); | |
| if (!IS_ENABLED(CONFIG_ARCH_HAS_PTE_SPECIAL)) | |
| return; | |
| pr_debug("Validating PTE special\n"); | |
| WARN_ON(!pte_special(pte_mkspecial(pte))); | |
| } | |
| static void __init pte_protnone_tests(struct pgtable_debug_args *args) | |
| { | |
| pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot_none); | |
| if (!IS_ENABLED(CONFIG_NUMA_BALANCING)) | |
| return; | |
| pr_debug("Validating PTE protnone\n"); | |
| WARN_ON(!pte_protnone(pte)); | |
| WARN_ON(!pte_present(pte)); | |
| } | |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
| static void __init pmd_protnone_tests(struct pgtable_debug_args *args) | |
| { | |
| pmd_t pmd; | |
| if (!IS_ENABLED(CONFIG_NUMA_BALANCING)) | |
| return; | |
| if (!has_transparent_hugepage()) | |
| return; | |
| pr_debug("Validating PMD protnone\n"); | |
| pmd = pmd_mkhuge(pfn_pmd(args->fixed_pmd_pfn, args->page_prot_none)); | |
| WARN_ON(!pmd_protnone(pmd)); | |
| WARN_ON(!pmd_present(pmd)); | |
| } | |
| #else /* !CONFIG_TRANSPARENT_HUGEPAGE */ | |
| static void __init pmd_protnone_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ | |
| #ifdef CONFIG_ARCH_HAS_PTE_DEVMAP | |
| static void __init pte_devmap_tests(struct pgtable_debug_args *args) | |
| { | |
| pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot); | |
| pr_debug("Validating PTE devmap\n"); | |
| WARN_ON(!pte_devmap(pte_mkdevmap(pte))); | |
| } | |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
| static void __init pmd_devmap_tests(struct pgtable_debug_args *args) | |
| { | |
| pmd_t pmd; | |
| if (!has_transparent_hugepage()) | |
| return; | |
| pr_debug("Validating PMD devmap\n"); | |
| pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot); | |
| WARN_ON(!pmd_devmap(pmd_mkdevmap(pmd))); | |
| } | |
| #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD | |
| static void __init pud_devmap_tests(struct pgtable_debug_args *args) | |
| { | |
| pud_t pud; | |
| if (!has_transparent_pud_hugepage()) | |
| return; | |
| pr_debug("Validating PUD devmap\n"); | |
| pud = pfn_pud(args->fixed_pud_pfn, args->page_prot); | |
| WARN_ON(!pud_devmap(pud_mkdevmap(pud))); | |
| } | |
| #else /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ | |
| static void __init pud_devmap_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ | |
| #else /* CONFIG_TRANSPARENT_HUGEPAGE */ | |
| static void __init pmd_devmap_tests(struct pgtable_debug_args *args) { } | |
| static void __init pud_devmap_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ | |
| #else | |
| static void __init pte_devmap_tests(struct pgtable_debug_args *args) { } | |
| static void __init pmd_devmap_tests(struct pgtable_debug_args *args) { } | |
| static void __init pud_devmap_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_ARCH_HAS_PTE_DEVMAP */ | |
| static void __init pte_soft_dirty_tests(struct pgtable_debug_args *args) | |
| { | |
| pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot); | |
| if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY)) | |
| return; | |
| pr_debug("Validating PTE soft dirty\n"); | |
| WARN_ON(!pte_soft_dirty(pte_mksoft_dirty(pte))); | |
| WARN_ON(pte_soft_dirty(pte_clear_soft_dirty(pte))); | |
| } | |
| static void __init pte_swap_soft_dirty_tests(struct pgtable_debug_args *args) | |
| { | |
| pte_t pte = pfn_pte(args->fixed_pte_pfn, args->page_prot); | |
| if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY)) | |
| return; | |
| pr_debug("Validating PTE swap soft dirty\n"); | |
| WARN_ON(!pte_swp_soft_dirty(pte_swp_mksoft_dirty(pte))); | |
| WARN_ON(pte_swp_soft_dirty(pte_swp_clear_soft_dirty(pte))); | |
| } | |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
| static void __init pmd_soft_dirty_tests(struct pgtable_debug_args *args) | |
| { | |
| pmd_t pmd; | |
| if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY)) | |
| return; | |
| if (!has_transparent_hugepage()) | |
| return; | |
| pr_debug("Validating PMD soft dirty\n"); | |
| pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot); | |
| WARN_ON(!pmd_soft_dirty(pmd_mksoft_dirty(pmd))); | |
| WARN_ON(pmd_soft_dirty(pmd_clear_soft_dirty(pmd))); | |
| } | |
| static void __init pmd_swap_soft_dirty_tests(struct pgtable_debug_args *args) | |
| { | |
| pmd_t pmd; | |
| if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY) || | |
| !IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION)) | |
| return; | |
| if (!has_transparent_hugepage()) | |
| return; | |
| pr_debug("Validating PMD swap soft dirty\n"); | |
| pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot); | |
| WARN_ON(!pmd_swp_soft_dirty(pmd_swp_mksoft_dirty(pmd))); | |
| WARN_ON(pmd_swp_soft_dirty(pmd_swp_clear_soft_dirty(pmd))); | |
| } | |
| #else /* !CONFIG_TRANSPARENT_HUGEPAGE */ | |
| static void __init pmd_soft_dirty_tests(struct pgtable_debug_args *args) { } | |
| static void __init pmd_swap_soft_dirty_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ | |
| static void __init pte_swap_exclusive_tests(struct pgtable_debug_args *args) | |
| { | |
| unsigned long max_swap_offset; | |
| swp_entry_t entry, entry2; | |
| pte_t pte; | |
| pr_debug("Validating PTE swap exclusive\n"); | |
| /* See generic_max_swapfile_size(): probe the maximum offset */ | |
| max_swap_offset = swp_offset(pte_to_swp_entry(swp_entry_to_pte(swp_entry(0, ~0UL)))); | |
| /* Create a swp entry with all possible bits set */ | |
| entry = swp_entry((1 << MAX_SWAPFILES_SHIFT) - 1, max_swap_offset); | |
| pte = swp_entry_to_pte(entry); | |
| WARN_ON(pte_swp_exclusive(pte)); | |
| WARN_ON(!is_swap_pte(pte)); | |
| entry2 = pte_to_swp_entry(pte); | |
| WARN_ON(memcmp(&entry, &entry2, sizeof(entry))); | |
| pte = pte_swp_mkexclusive(pte); | |
| WARN_ON(!pte_swp_exclusive(pte)); | |
| WARN_ON(!is_swap_pte(pte)); | |
| WARN_ON(pte_swp_soft_dirty(pte)); | |
| entry2 = pte_to_swp_entry(pte); | |
| WARN_ON(memcmp(&entry, &entry2, sizeof(entry))); | |
| pte = pte_swp_clear_exclusive(pte); | |
| WARN_ON(pte_swp_exclusive(pte)); | |
| WARN_ON(!is_swap_pte(pte)); | |
| entry2 = pte_to_swp_entry(pte); | |
| WARN_ON(memcmp(&entry, &entry2, sizeof(entry))); | |
| } | |
| static void __init pte_swap_tests(struct pgtable_debug_args *args) | |
| { | |
| swp_entry_t swp; | |
| pte_t pte; | |
| pr_debug("Validating PTE swap\n"); | |
| pte = pfn_pte(args->fixed_pte_pfn, args->page_prot); | |
| swp = __pte_to_swp_entry(pte); | |
| pte = __swp_entry_to_pte(swp); | |
| WARN_ON(args->fixed_pte_pfn != pte_pfn(pte)); | |
| } | |
| #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION | |
| static void __init pmd_swap_tests(struct pgtable_debug_args *args) | |
| { | |
| swp_entry_t swp; | |
| pmd_t pmd; | |
| if (!has_transparent_hugepage()) | |
| return; | |
| pr_debug("Validating PMD swap\n"); | |
| pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot); | |
| swp = __pmd_to_swp_entry(pmd); | |
| pmd = __swp_entry_to_pmd(swp); | |
| WARN_ON(args->fixed_pmd_pfn != pmd_pfn(pmd)); | |
| } | |
| #else /* !CONFIG_ARCH_ENABLE_THP_MIGRATION */ | |
| static void __init pmd_swap_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */ | |
| static void __init swap_migration_tests(struct pgtable_debug_args *args) | |
| { | |
| struct page *page; | |
| swp_entry_t swp; | |
| if (!IS_ENABLED(CONFIG_MIGRATION)) | |
| return; | |
| /* | |
| * swap_migration_tests() requires a dedicated page as it needs to | |
| * be locked before creating a migration entry from it. Locking the | |
| * page that actually maps kernel text ('start_kernel') can be real | |
| * problematic. Lets use the allocated page explicitly for this | |
| * purpose. | |
| */ | |
| page = (args->pte_pfn != ULONG_MAX) ? pfn_to_page(args->pte_pfn) : NULL; | |
| if (!page) | |
| return; | |
| pr_debug("Validating swap migration\n"); | |
| /* | |
| * make_[readable|writable]_migration_entry() expects given page to | |
| * be locked, otherwise it stumbles upon a BUG_ON(). | |
| */ | |
| __SetPageLocked(page); | |
| swp = make_writable_migration_entry(page_to_pfn(page)); | |
| WARN_ON(!is_migration_entry(swp)); | |
| WARN_ON(!is_writable_migration_entry(swp)); | |
| swp = make_readable_migration_entry(swp_offset(swp)); | |
| WARN_ON(!is_migration_entry(swp)); | |
| WARN_ON(is_writable_migration_entry(swp)); | |
| swp = make_readable_migration_entry(page_to_pfn(page)); | |
| WARN_ON(!is_migration_entry(swp)); | |
| WARN_ON(is_writable_migration_entry(swp)); | |
| __ClearPageLocked(page); | |
| } | |
| #ifdef CONFIG_HUGETLB_PAGE | |
| static void __init hugetlb_basic_tests(struct pgtable_debug_args *args) | |
| { | |
| struct page *page; | |
| pte_t pte; | |
| pr_debug("Validating HugeTLB basic\n"); | |
| /* | |
| * Accessing the page associated with the pfn is safe here, | |
| * as it was previously derived from a real kernel symbol. | |
| */ | |
| page = pfn_to_page(args->fixed_pmd_pfn); | |
| pte = mk_huge_pte(page, args->page_prot); | |
| WARN_ON(!huge_pte_dirty(huge_pte_mkdirty(pte))); | |
| WARN_ON(!huge_pte_write(huge_pte_mkwrite(huge_pte_wrprotect(pte)))); | |
| WARN_ON(huge_pte_write(huge_pte_wrprotect(huge_pte_mkwrite(pte)))); | |
| #ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB | |
| pte = pfn_pte(args->fixed_pmd_pfn, args->page_prot); | |
| WARN_ON(!pte_huge(arch_make_huge_pte(pte, PMD_SHIFT, VM_ACCESS_FLAGS))); | |
| #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */ | |
| } | |
| #else /* !CONFIG_HUGETLB_PAGE */ | |
| static void __init hugetlb_basic_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_HUGETLB_PAGE */ | |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
| static void __init pmd_thp_tests(struct pgtable_debug_args *args) | |
| { | |
| pmd_t pmd; | |
| if (!has_transparent_hugepage()) | |
| return; | |
| pr_debug("Validating PMD based THP\n"); | |
| /* | |
| * pmd_trans_huge() and pmd_present() must return positive after | |
| * MMU invalidation with pmd_mkinvalid(). This behavior is an | |
| * optimization for transparent huge page. pmd_trans_huge() must | |
| * be true if pmd_page() returns a valid THP to avoid taking the | |
| * pmd_lock when others walk over non transhuge pmds (i.e. there | |
| * are no THP allocated). Especially when splitting a THP and | |
| * removing the present bit from the pmd, pmd_trans_huge() still | |
| * needs to return true. pmd_present() should be true whenever | |
| * pmd_trans_huge() returns true. | |
| */ | |
| pmd = pfn_pmd(args->fixed_pmd_pfn, args->page_prot); | |
| WARN_ON(!pmd_trans_huge(pmd_mkhuge(pmd))); | |
| #ifndef __HAVE_ARCH_PMDP_INVALIDATE | |
| WARN_ON(!pmd_trans_huge(pmd_mkinvalid(pmd_mkhuge(pmd)))); | |
| WARN_ON(!pmd_present(pmd_mkinvalid(pmd_mkhuge(pmd)))); | |
| WARN_ON(!pmd_leaf(pmd_mkinvalid(pmd_mkhuge(pmd)))); | |
| #endif /* __HAVE_ARCH_PMDP_INVALIDATE */ | |
| } | |
| #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD | |
| static void __init pud_thp_tests(struct pgtable_debug_args *args) | |
| { | |
| pud_t pud; | |
| if (!has_transparent_pud_hugepage()) | |
| return; | |
| pr_debug("Validating PUD based THP\n"); | |
| pud = pfn_pud(args->fixed_pud_pfn, args->page_prot); | |
| WARN_ON(!pud_trans_huge(pud_mkhuge(pud))); | |
| /* | |
| * pud_mkinvalid() has been dropped for now. Enable back | |
| * these tests when it comes back with a modified pud_present(). | |
| * | |
| * WARN_ON(!pud_trans_huge(pud_mkinvalid(pud_mkhuge(pud)))); | |
| * WARN_ON(!pud_present(pud_mkinvalid(pud_mkhuge(pud)))); | |
| */ | |
| } | |
| #else /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ | |
| static void __init pud_thp_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ | |
| #else /* !CONFIG_TRANSPARENT_HUGEPAGE */ | |
| static void __init pmd_thp_tests(struct pgtable_debug_args *args) { } | |
| static void __init pud_thp_tests(struct pgtable_debug_args *args) { } | |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ | |
| static unsigned long __init get_random_vaddr(void) | |
| { | |
| unsigned long random_vaddr, random_pages, total_user_pages; | |
| total_user_pages = (TASK_SIZE - FIRST_USER_ADDRESS) / PAGE_SIZE; | |
| random_pages = get_random_long() % total_user_pages; | |
| random_vaddr = FIRST_USER_ADDRESS + random_pages * PAGE_SIZE; | |
| return random_vaddr; | |
| } | |
| static void __init destroy_args(struct pgtable_debug_args *args) | |
| { | |
| struct page *page = NULL; | |
| /* Free (huge) page */ | |
| if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && | |
| has_transparent_pud_hugepage() && | |
| args->pud_pfn != ULONG_MAX) { | |
| if (args->is_contiguous_page) { | |
| free_contig_range(args->pud_pfn, | |
| (1 << (HPAGE_PUD_SHIFT - PAGE_SHIFT))); | |
| } else { | |
| page = pfn_to_page(args->pud_pfn); | |
| __free_pages(page, HPAGE_PUD_SHIFT - PAGE_SHIFT); | |
| } | |
| args->pud_pfn = ULONG_MAX; | |
| args->pmd_pfn = ULONG_MAX; | |
| args->pte_pfn = ULONG_MAX; | |
| } | |
| if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && | |
| has_transparent_hugepage() && | |
| args->pmd_pfn != ULONG_MAX) { | |
| if (args->is_contiguous_page) { | |
| free_contig_range(args->pmd_pfn, (1 << HPAGE_PMD_ORDER)); | |
| } else { | |
| page = pfn_to_page(args->pmd_pfn); | |
| __free_pages(page, HPAGE_PMD_ORDER); | |
| } | |
| args->pmd_pfn = ULONG_MAX; | |
| args->pte_pfn = ULONG_MAX; | |
| } | |
| if (args->pte_pfn != ULONG_MAX) { | |
| page = pfn_to_page(args->pte_pfn); | |
| __free_page(page); | |
| args->pte_pfn = ULONG_MAX; | |
| } | |
| /* Free page table entries */ | |
| if (args->start_ptep) { | |
| pmd_clear(args->pmdp); | |
| pte_free(args->mm, args->start_ptep); | |
| mm_dec_nr_ptes(args->mm); | |
| } | |
| if (args->start_pmdp) { | |
| pud_clear(args->pudp); | |
| pmd_free(args->mm, args->start_pmdp); | |
| mm_dec_nr_pmds(args->mm); | |
| } | |
| if (args->start_pudp) { | |
| p4d_clear(args->p4dp); | |
| pud_free(args->mm, args->start_pudp); | |
| mm_dec_nr_puds(args->mm); | |
| } | |
| if (args->start_p4dp) { | |
| pgd_clear(args->pgdp); | |
| p4d_free(args->mm, args->start_p4dp); | |
| } | |
| /* Free vma and mm struct */ | |
| if (args->vma) | |
| vm_area_free(args->vma); | |
| if (args->mm) | |
| mmput(args->mm); | |
| } | |
| static struct page * __init | |
| debug_vm_pgtable_alloc_huge_page(struct pgtable_debug_args *args, int order) | |
| { | |
| struct page *page = NULL; | |
| #ifdef CONFIG_CONTIG_ALLOC | |
| if (order > MAX_PAGE_ORDER) { | |
| page = alloc_contig_pages((1 << order), GFP_KERNEL, | |
| first_online_node, NULL); | |
| if (page) { | |
| args->is_contiguous_page = true; | |
| return page; | |
| } | |
| } | |
| #endif | |
| if (order <= MAX_PAGE_ORDER) | |
| page = alloc_pages(GFP_KERNEL, order); | |
| return page; | |
| } | |
| /* | |
| * Check if a physical memory range described by <pstart, pend> contains | |
| * an area that is of size psize, and aligned to psize. | |
| * | |
| * Don't use address 0, an all-zeroes physical address might mask bugs, and | |
| * it's not used on x86. | |
| */ | |
| static void __init phys_align_check(phys_addr_t pstart, | |
| phys_addr_t pend, unsigned long psize, | |
| phys_addr_t *physp, unsigned long *alignp) | |
| { | |
| phys_addr_t aligned_start, aligned_end; | |
| if (pstart == 0) | |
| pstart = PAGE_SIZE; | |
| aligned_start = ALIGN(pstart, psize); | |
| aligned_end = aligned_start + psize; | |
| if (aligned_end > aligned_start && aligned_end <= pend) { | |
| *alignp = psize; | |
| *physp = aligned_start; | |
| } | |
| } | |
| static void __init init_fixed_pfns(struct pgtable_debug_args *args) | |
| { | |
| u64 idx; | |
| phys_addr_t phys, pstart, pend; | |
| /* | |
| * Initialize the fixed pfns. To do this, try to find a | |
| * valid physical range, preferably aligned to PUD_SIZE, | |
| * but settling for aligned to PMD_SIZE as a fallback. If | |
| * neither of those is found, use the physical address of | |
| * the start_kernel symbol. | |
| * | |
| * The memory doesn't need to be allocated, it just needs to exist | |
| * as usable memory. It won't be touched. | |
| * | |
| * The alignment is recorded, and can be checked to see if we | |
| * can run the tests that require an actual valid physical | |
| * address range on some architectures ({pmd,pud}_huge_test | |
| * on x86). | |
| */ | |
| phys = __pa_symbol(&start_kernel); | |
| args->fixed_alignment = PAGE_SIZE; | |
| for_each_mem_range(idx, &pstart, &pend) { | |
| /* First check for a PUD-aligned area */ | |
| phys_align_check(pstart, pend, PUD_SIZE, &phys, | |
| &args->fixed_alignment); | |
| /* If a PUD-aligned area is found, we're done */ | |
| if (args->fixed_alignment == PUD_SIZE) | |
| break; | |
| /* | |
| * If no PMD-aligned area found yet, check for one, | |
| * but continue the loop to look for a PUD-aligned area. | |
| */ | |
| if (args->fixed_alignment < PMD_SIZE) | |
| phys_align_check(pstart, pend, PMD_SIZE, &phys, | |
| &args->fixed_alignment); | |
| } | |
| args->fixed_pgd_pfn = __phys_to_pfn(phys & PGDIR_MASK); | |
| args->fixed_p4d_pfn = __phys_to_pfn(phys & P4D_MASK); | |
| args->fixed_pud_pfn = __phys_to_pfn(phys & PUD_MASK); | |
| args->fixed_pmd_pfn = __phys_to_pfn(phys & PMD_MASK); | |
| args->fixed_pte_pfn = __phys_to_pfn(phys & PAGE_MASK); | |
| WARN_ON(!pfn_valid(args->fixed_pte_pfn)); | |
| } | |
| static int __init init_args(struct pgtable_debug_args *args) | |
| { | |
| struct page *page = NULL; | |
| int ret = 0; | |
| /* | |
| * Initialize the debugging data. | |
| * | |
| * vm_get_page_prot(VM_NONE) or vm_get_page_prot(VM_SHARED|VM_NONE) | |
| * will help create page table entries with PROT_NONE permission as | |
| * required for pxx_protnone_tests(). | |
| */ | |
| memset(args, 0, sizeof(*args)); | |
| args->vaddr = get_random_vaddr(); | |
| args->page_prot = vm_get_page_prot(VM_ACCESS_FLAGS); | |
| args->page_prot_none = vm_get_page_prot(VM_NONE); | |
| args->is_contiguous_page = false; | |
| args->pud_pfn = ULONG_MAX; | |
| args->pmd_pfn = ULONG_MAX; | |
| args->pte_pfn = ULONG_MAX; | |
| args->fixed_pgd_pfn = ULONG_MAX; | |
| args->fixed_p4d_pfn = ULONG_MAX; | |
| args->fixed_pud_pfn = ULONG_MAX; | |
| args->fixed_pmd_pfn = ULONG_MAX; | |
| args->fixed_pte_pfn = ULONG_MAX; | |
| /* Allocate mm and vma */ | |
| args->mm = mm_alloc(); | |
| if (!args->mm) { | |
| pr_err("Failed to allocate mm struct\n"); | |
| ret = -ENOMEM; | |
| goto error; | |
| } | |
| args->vma = vm_area_alloc(args->mm); | |
| if (!args->vma) { | |
| pr_err("Failed to allocate vma\n"); | |
| ret = -ENOMEM; | |
| goto error; | |
| } | |
| /* | |
| * Allocate page table entries. They will be modified in the tests. | |
| * Lets save the page table entries so that they can be released | |
| * when the tests are completed. | |
| */ | |
| args->pgdp = pgd_offset(args->mm, args->vaddr); | |
| args->p4dp = p4d_alloc(args->mm, args->pgdp, args->vaddr); | |
| if (!args->p4dp) { | |
| pr_err("Failed to allocate p4d entries\n"); | |
| ret = -ENOMEM; | |
| goto error; | |
| } | |
| args->start_p4dp = p4d_offset(args->pgdp, 0UL); | |
| WARN_ON(!args->start_p4dp); | |
| args->pudp = pud_alloc(args->mm, args->p4dp, args->vaddr); | |
| if (!args->pudp) { | |
| pr_err("Failed to allocate pud entries\n"); | |
| ret = -ENOMEM; | |
| goto error; | |
| } | |
| args->start_pudp = pud_offset(args->p4dp, 0UL); | |
| WARN_ON(!args->start_pudp); | |
| args->pmdp = pmd_alloc(args->mm, args->pudp, args->vaddr); | |
| if (!args->pmdp) { | |
| pr_err("Failed to allocate pmd entries\n"); | |
| ret = -ENOMEM; | |
| goto error; | |
| } | |
| args->start_pmdp = pmd_offset(args->pudp, 0UL); | |
| WARN_ON(!args->start_pmdp); | |
| if (pte_alloc(args->mm, args->pmdp)) { | |
| pr_err("Failed to allocate pte entries\n"); | |
| ret = -ENOMEM; | |
| goto error; | |
| } | |
| args->start_ptep = pmd_pgtable(pmdp_get(args->pmdp)); | |
| WARN_ON(!args->start_ptep); | |
| init_fixed_pfns(args); | |
| /* | |
| * Allocate (huge) pages because some of the tests need to access | |
| * the data in the pages. The corresponding tests will be skipped | |
| * if we fail to allocate (huge) pages. | |
| */ | |
| if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && | |
| has_transparent_pud_hugepage()) { | |
| page = debug_vm_pgtable_alloc_huge_page(args, | |
| HPAGE_PUD_SHIFT - PAGE_SHIFT); | |
| if (page) { | |
| args->pud_pfn = page_to_pfn(page); | |
| args->pmd_pfn = args->pud_pfn; | |
| args->pte_pfn = args->pud_pfn; | |
| return 0; | |
| } | |
| } | |
| if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && | |
| has_transparent_hugepage()) { | |
| page = debug_vm_pgtable_alloc_huge_page(args, HPAGE_PMD_ORDER); | |
| if (page) { | |
| args->pmd_pfn = page_to_pfn(page); | |
| args->pte_pfn = args->pmd_pfn; | |
| return 0; | |
| } | |
| } | |
| page = alloc_page(GFP_KERNEL); | |
| if (page) | |
| args->pte_pfn = page_to_pfn(page); | |
| return 0; | |
| error: | |
| destroy_args(args); | |
| return ret; | |
| } | |
| static int __init debug_vm_pgtable(void) | |
| { | |
| struct pgtable_debug_args args; | |
| spinlock_t *ptl = NULL; | |
| int idx, ret; | |
| pr_info("Validating architecture page table helpers\n"); | |
| ret = init_args(&args); | |
| if (ret) | |
| return ret; | |
| /* | |
| * Iterate over each possible vm_flags to make sure that all | |
| * the basic page table transformation validations just hold | |
| * true irrespective of the starting protection value for a | |
| * given page table entry. | |
| * | |
| * Protection based vm_flags combinations are always linear | |
| * and increasing i.e starting from VM_NONE and going up to | |
| * (VM_SHARED | READ | WRITE | EXEC). | |
| */ | |
| #define VM_FLAGS_START (VM_NONE) | |
| #define VM_FLAGS_END (VM_SHARED | VM_EXEC | VM_WRITE | VM_READ) | |
| for (idx = VM_FLAGS_START; idx <= VM_FLAGS_END; idx++) { | |
| pte_basic_tests(&args, idx); | |
| pmd_basic_tests(&args, idx); | |
| pud_basic_tests(&args, idx); | |
| } | |
| /* | |
| * Both P4D and PGD level tests are very basic which do not | |
| * involve creating page table entries from the protection | |
| * value and the given pfn. Hence just keep them out from | |
| * the above iteration for now to save some test execution | |
| * time. | |
| */ | |
| p4d_basic_tests(&args); | |
| pgd_basic_tests(&args); | |
| pmd_leaf_tests(&args); | |
| pud_leaf_tests(&args); | |
| pte_special_tests(&args); | |
| pte_protnone_tests(&args); | |
| pmd_protnone_tests(&args); | |
| pte_devmap_tests(&args); | |
| pmd_devmap_tests(&args); | |
| pud_devmap_tests(&args); | |
| pte_soft_dirty_tests(&args); | |
| pmd_soft_dirty_tests(&args); | |
| pte_swap_soft_dirty_tests(&args); | |
| pmd_swap_soft_dirty_tests(&args); | |
| pte_swap_exclusive_tests(&args); | |
| pte_swap_tests(&args); | |
| pmd_swap_tests(&args); | |
| swap_migration_tests(&args); | |
| pmd_thp_tests(&args); | |
| pud_thp_tests(&args); | |
| hugetlb_basic_tests(&args); | |
| /* | |
| * Page table modifying tests. They need to hold | |
| * proper page table lock. | |
| */ | |
| args.ptep = pte_offset_map_lock(args.mm, args.pmdp, args.vaddr, &ptl); | |
| pte_clear_tests(&args); | |
| pte_advanced_tests(&args); | |
| if (args.ptep) | |
| pte_unmap_unlock(args.ptep, ptl); | |
| ptl = pmd_lock(args.mm, args.pmdp); | |
| pmd_clear_tests(&args); | |
| pmd_advanced_tests(&args); | |
| pmd_huge_tests(&args); | |
| pmd_populate_tests(&args); | |
| spin_unlock(ptl); | |
| ptl = pud_lock(args.mm, args.pudp); | |
| pud_clear_tests(&args); | |
| pud_advanced_tests(&args); | |
| pud_huge_tests(&args); | |
| pud_populate_tests(&args); | |
| spin_unlock(ptl); | |
| spin_lock(&(args.mm->page_table_lock)); | |
| p4d_clear_tests(&args); | |
| pgd_clear_tests(&args); | |
| p4d_populate_tests(&args); | |
| pgd_populate_tests(&args); | |
| spin_unlock(&(args.mm->page_table_lock)); | |
| destroy_args(&args); | |
| return 0; | |
| } | |
| late_initcall(debug_vm_pgtable); |