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

[ Upstream commit 00de2c9f26b15f1a6f2af516dd8ec5f8d28189b7 ]

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().

Link: https://lkml.kernel.org/r/20230810093241.1181142-1-qi.zheng@linux.dev
Fixes: 42b2547137f5 ("arm64/mm: enable ARCH_SUPPORTS_PAGE_TABLE_CHECK")
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 95364e8bdc194491ce298197d1a52896af511c53..50a8e7ab5fa9427ef46796c33112337b968282cf 100644 (file)
--- 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);
 }