arm64: Do not synchronise I and D caches for special ptes

Special pte mappings are not intended to be executable and do not even
have an associated struct page. This patch ensures that we do not call
__sync_icache_dcache() on such ptes.

Signed-off-by: Catalin Marinas <[email protected]>
Reported-by: Steve Capper <[email protected]>
Tested-by: Laura Abbott <[email protected]>
Tested-by: Bharat Bhushan <[email protected]>
Cc: <[email protected]>

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 2d3cede6270904006d1e5b14aa7a09b5201a22bc..72c9ac38cdd97455e47656acf3f67cf02ef485c8 100644 (file)
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -199,7 +199,7 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
                              pte_t *ptep, pte_t pte)
 {
        if (pte_valid_user(pte)) {
-               if (pte_exec(pte))
+               if (!pte_special(pte) && pte_exec(pte))
                        __sync_icache_dcache(pte, addr);
                if (pte_dirty(pte) && pte_write(pte))
                        pte_val(pte) &= ~PTE_RDONLY;