Re: [PATCH v1 06/46] powerpc/kasan: Refactor update of early shadow mappings
From: Christophe Leroy <hidden>
Date: 2020-04-02 10:19:24
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Michael, Le 16/03/2020 à 13:35, Christophe Leroy a écrit :
kasan_remap_early_shadow_ro() and kasan_unmap_early_shadow_vmalloc() are both updating the early shadow mapping: the first one sets the mapping read-only while the other clears the mapping. Refactor and create kasan_update_early_region()
There is a trivial conflict with this patch on powerpc/next. Do you plan to take this series for 5.7 ? I so, I can repost the series now with the fix, or just this patch ? Otherwise, what are your plans ? This series (Patches 18 and 19) will conflict with the 40x removal series as both do things about that PTE_ATOMIC_UPDATE stuff. Which series would go first ? Thanks Christophe
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Signed-off-by: Christophe Leroy <redacted> --- arch/powerpc/mm/kasan/kasan_init_32.c | 39 +++++++++++++-------------- 1 file changed, 18 insertions(+), 21 deletions(-)diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/kasan_init_32.c index c9d053078c37..65fd8b891f8e 100644 --- a/arch/powerpc/mm/kasan/kasan_init_32.c +++ b/arch/powerpc/mm/kasan/kasan_init_32.c@@ -79,45 +79,42 @@ static int __init kasan_init_region(void *start, size_t size) return 0; } -static void __init kasan_remap_early_shadow_ro(void) +static void __init +kasan_update_early_region(unsigned long k_start, unsigned long k_end, pte_t pte) { - pgprot_t prot = kasan_prot_ro(); - unsigned long k_start = KASAN_SHADOW_START; - unsigned long k_end = KASAN_SHADOW_END; unsigned long k_cur; phys_addr_t pa = __pa(kasan_early_shadow_page); - kasan_populate_pte(kasan_early_shadow_pte, prot); - - for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) { + for (k_cur = k_start; k_cur < k_end; k_cur += PAGE_SIZE) { pmd_t *pmd = pmd_ptr_k(k_cur); pte_t *ptep = pte_offset_kernel(pmd, k_cur); if ((pte_val(*ptep) & PTE_RPN_MASK) != pa) continue; - __set_pte_at(&init_mm, k_cur, ptep, pfn_pte(PHYS_PFN(pa), prot), 0); + __set_pte_at(&init_mm, k_cur, ptep, pte, 0); } - flush_tlb_kernel_range(KASAN_SHADOW_START, KASAN_SHADOW_END); + + flush_tlb_kernel_range(k_start, k_end); } -static void __init kasan_unmap_early_shadow_vmalloc(void) +static void __init kasan_remap_early_shadow_ro(void) { - unsigned long k_start = (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_START); - unsigned long k_end = (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_END); - unsigned long k_cur; + pgprot_t prot = kasan_prot_ro(); phys_addr_t pa = __pa(kasan_early_shadow_page); - for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) { - pmd_t *pmd = pmd_offset(pud_offset(pgd_offset_k(k_cur), k_cur), k_cur); - pte_t *ptep = pte_offset_kernel(pmd, k_cur); + kasan_populate_pte(kasan_early_shadow_pte, prot); - if ((pte_val(*ptep) & PTE_RPN_MASK) != pa) - continue; + kasan_update_early_region(KASAN_SHADOW_START, KASAN_SHADOW_END, + pfn_pte(PHYS_PFN(pa), prot)); +} - __set_pte_at(&init_mm, k_cur, ptep, __pte(0), 0); - } - flush_tlb_kernel_range(k_start, k_end); +static void __init kasan_unmap_early_shadow_vmalloc(void) +{ + unsigned long k_start = (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_START); + unsigned long k_end = (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_END); + + kasan_update_early_region(k_start, k_end, __pte(0)); } static void __init kasan_mmu_init(void)