[RFC 2/4] arm64/mm: Call pte_sw_mkdirty() while preserving the HW dirty state

[Anshuman Khandual]

pte_mkdirty() creates dirty states both in SW and HW bits which is really
not required either in pte_wrprotect() or pte_modify() for preserving the
HW dirty state. Instead pte_sw_mkdirty() is sufficient.

Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
 arch/arm64/include/asm/pgtable.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index fb03be697819..dd20b752ed48 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -244,7 +244,7 @@ static inline pte_t pte_wrprotect(pte_t pte)
 	 * clear), set the PTE_DIRTY bit.
 	 */
 	if (pte_hw_dirty(pte))
-		pte = pte_mkdirty(pte);
+		pte = pte_sw_mkdirty(pte);
 
 	pte = clear_pte_bit(pte, __pgprot(PTE_WRITE));
 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
@@ -855,7 +855,7 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 			      PTE_ATTRINDX_MASK;
 	/* preserve the hardware dirty information */
 	if (pte_hw_dirty(pte))
-		pte = pte_mkdirty(pte);
+		pte = pte_sw_mkdirty(pte);
 	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
 	return pte;
 }
-- 
2.30.2