2 files changed, 7 insertions, 1 deletions

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 2c5c18c2464d..4adb33628dec 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -777,6 +777,9 @@ static int do_change_page_attr_set_clr(unsigned long addr, int numpages,
                 WARN_ON_ONCE(1);
         }
 
+        /* Must avoid aliasing mappings in the highmem code */
+        kmap_flush_unused();
+
         cpa.vaddr = addr;
         cpa.numpages = numpages;
         cpa.mask_set = mask_set;
diff --git a/mm/highmem.c b/mm/highmem.c
index e16e1523b688..b36b83b920ff 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -70,6 +70,7 @@ static DECLARE_WAIT_QUEUE_HEAD(pkmap_map_wait);
 static void flush_all_zero_pkmaps(void)
 {
         int i;
+        int need_flush = 0;
 
         flush_cache_kmaps();
 
@@ -101,8 +102,10 @@ static void flush_all_zero_pkmaps(void)
                           &pkmap_page_table[i]);
 
                 set_page_address(page, NULL);
+                need_flush = 1;
         }
-        flush_tlb_kernel_range(PKMAP_ADDR(0), PKMAP_ADDR(LAST_PKMAP));
+        if (need_flush)
+                flush_tlb_kernel_range(PKMAP_ADDR(0), PKMAP_ADDR(LAST_PKMAP));
 }
 
 /**