[PATCH] arm64: mm: use ptep_clear() instead of pte_clear() in clear_flush()

Qi Zheng
2023-08-10T09:35:55Z

From: Qi Zheng <zhengqi.arch@bytedance.com>

In clear_flush(), the original pte may be a present entry, so we should
use ptep_clear() to let page_table_check track the pte clearing operation,
otherwise it may cause false positive in subsequent set_pte_at().

Fixes: 42b2547137f5 ("arm64/mm: enable ARCH_SUPPORTS_PAGE_TABLE_CHECK")
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
---
arch/arm64/mm/hugetlbpage.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 21716c940682..9c52718ea750 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -236,7 +236,7 @@ static void clear_flush(struct mm_struct *mm,
unsigned long i, saddr = addr;

for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
- pte_clear(mm, addr, ptep);
+ ptep_clear(mm, addr, ptep);

flush_tlb_range(&vma, saddr, addr);
}
--
2.30.2