s390/mm: implement software dirty bits

[cascardo/linux.git] / arch / s390 / lib / uaccess_pt.c

diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c
index 9017a63..a70ee84 100644 (file)
--- a/arch/s390/lib/uaccess_pt.c
+++ b/arch/s390/lib/uaccess_pt.c
@@ -50,7 +50,7 @@ static __always_inline unsigned long follow_table(struct mm_struct *mm,
        ptep = pte_offset_map(pmd, addr);
        if (!pte_present(*ptep))
                return -0x11UL;
-       if (write && !pte_write(*ptep))
+       if (write && (!pte_write(*ptep) || !pte_dirty(*ptep)))
                return -0x04UL;
 
        return (pte_val(*ptep) & PAGE_MASK) + (addr & ~PAGE_MASK);