[PATCH] x86_64 add NX mask for PTE entry

["bibo,mao" <bibo.mao@intel.com>]

Hi,
    If function change_page_attr_addr calls revert_page to revert
to original pte value, mk_pte_phys does not mask NX bit. If NX bit
is set on no NX hardware supported x86_64 machine, there is will
be RSVD type page fault and system will crash. This patch adds NX
mask bit for PTE entry.

Signed-off-by: bibo,mao <bibo.mao@intel.com>

diff --git a/include/asm-x86_64/pgtable.h b/include/asm-x86_64/pgtable.h
index 6899e77..0555c1c 100644
--- a/include/asm-x86_64/pgtable.h
+++ b/include/asm-x86_64/pgtable.h
@@ -366,6 +366,7 @@ static inline pte_t mk_pte_phys(unsigned
  {
  	pte_t pte;
  	pte_val(pte) = physpage | pgprot_val(pgprot);
+	pte_val(pte) &= __supported_pte_mask;
  	return pte;
  }