1 files changed, 30 insertions, 10 deletions

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 4fadfd2b7017..3bded76e8d5c 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -93,6 +93,18 @@ void arch_report_meminfo(struct seq_file *m)
 static inline void split_page_count(int level) { }
 #endif
 
+static inline int
+within(unsigned long addr, unsigned long start, unsigned long end)
+{
+        return addr >= start && addr < end;
+}
+
+static inline int
+within_inclusive(unsigned long addr, unsigned long start, unsigned long end)
+{
+        return addr >= start && addr <= end;
+}
+
 #ifdef CONFIG_X86_64
 
 static inline unsigned long highmap_start_pfn(void)
@@ -106,20 +118,25 @@ static inline unsigned long highmap_end_pfn(void)
         return __pa_symbol(roundup(_brk_end, PMD_SIZE) - 1) >> PAGE_SHIFT;
 }
 
-#endif
-
-static inline int
-within(unsigned long addr, unsigned long start, unsigned long end)
+static bool __cpa_pfn_in_highmap(unsigned long pfn)
 {
-        return addr >= start && addr < end;
+        /*
+         * Kernel text has an alias mapping at a high address, known
+         * here as "highmap".
+         */
+        return within_inclusive(pfn, highmap_start_pfn(), highmap_end_pfn());
 }
 
-static inline int
-within_inclusive(unsigned long addr, unsigned long start, unsigned long end)
+#else
+
+static bool __cpa_pfn_in_highmap(unsigned long pfn)
 {
-        return addr >= start && addr <= end;
+        /* There is no highmap on 32-bit */
+        return false;
 }
 
+#endif
+
 /*
  * Flushing functions
  */
@@ -1183,6 +1200,10 @@ static int __cpa_process_fault(struct cpa_data *cpa, unsigned long vaddr,
                 cpa->numpages = 1;
                 cpa->pfn = __pa(vaddr) >> PAGE_SHIFT;
                 return 0;
+
+        } else if (__cpa_pfn_in_highmap(cpa->pfn)) {
+                /* Faults in the highmap are OK, so do not warn: */
+                return -EFAULT;
         } else {
                 WARN(1, KERN_WARNING "CPA: called for zero pte. "
                         "vaddr = %lx cpa->vaddr = %lx\n", vaddr,
@@ -1335,8 +1356,7 @@ static int cpa_process_alias(struct cpa_data *cpa)
          * to touch the high mapped kernel as well:
          */
         if (!within(vaddr, (unsigned long)_text, _brk_end) &&
-            within_inclusive(cpa->pfn, highmap_start_pfn(),
-                             highmap_end_pfn())) {
+            __cpa_pfn_in_highmap(cpa->pfn)) {
                 unsigned long temp_cpa_vaddr = (cpa->pfn << PAGE_SHIFT) +
                                                __START_KERNEL_map - phys_base;
                 alias_cpa = *cpa;