From edf955647269422e387732870d04fc15933a25ea Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Wed, 13 Dec 2023 21:30:01 +0100 Subject: riscv: Use accessors to page table entries instead of direct dereference As very well explained in commit 20a004e7b017 ("arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables"), an architecture whose page table walker can modify the PTE in parallel must use READ_ONCE()/WRITE_ONCE() macro to avoid any compiler transformation. So apply that to riscv which is such architecture. Signed-off-by: Alexandre Ghiti Acked-by: Anup Patel Link: https://lore.kernel.org/r/20231213203001.179237-5-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt --- arch/riscv/mm/hugetlbpage.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'arch/riscv/mm/hugetlbpage.c') diff --git a/arch/riscv/mm/hugetlbpage.c b/arch/riscv/mm/hugetlbpage.c index b52f0210481f..431596c0e20e 100644 --- a/arch/riscv/mm/hugetlbpage.c +++ b/arch/riscv/mm/hugetlbpage.c @@ -54,7 +54,7 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, } if (sz == PMD_SIZE) { - if (want_pmd_share(vma, addr) && pud_none(*pud)) + if (want_pmd_share(vma, addr) && pud_none(pudp_get(pud))) pte = huge_pmd_share(mm, vma, addr, pud); else pte = (pte_t *)pmd_alloc(mm, pud, addr); @@ -93,11 +93,11 @@ pte_t *huge_pte_offset(struct mm_struct *mm, pmd_t *pmd; pgd = pgd_offset(mm, addr); - if (!pgd_present(*pgd)) + if (!pgd_present(pgdp_get(pgd))) return NULL; p4d = p4d_offset(pgd, addr); - if (!p4d_present(*p4d)) + if (!p4d_present(p4dp_get(p4d))) return NULL; pud = pud_offset(p4d, addr); @@ -105,7 +105,7 @@ pte_t *huge_pte_offset(struct mm_struct *mm, /* must be pud huge, non-present or none */ return (pte_t *)pud; - if (!pud_present(*pud)) + if (!pud_present(pudp_get(pud))) return NULL; pmd = pmd_offset(pud, addr); @@ -113,7 +113,7 @@ pte_t *huge_pte_offset(struct mm_struct *mm, /* must be pmd huge, non-present or none */ return (pte_t *)pmd; - if (!pmd_present(*pmd)) + if (!pmd_present(pmdp_get(pmd))) return NULL; for_each_napot_order(order) { @@ -293,7 +293,7 @@ void huge_pte_clear(struct mm_struct *mm, pte_t *ptep, unsigned long sz) { - pte_t pte = READ_ONCE(*ptep); + pte_t pte = ptep_get(ptep); int i, pte_num; if (!pte_napot(pte)) { -- cgit v1.2.3-70-g09d2