3 files changed, 20 insertions, 8 deletions

diff --git a/arch/x86/kernel/cpu/mtrr/cleanup.c b/arch/x86/kernel/cpu/mtrr/cleanup.c
index 58b58bbf7eb3..f4f89fbc228f 100644
--- a/arch/x86/kernel/cpu/mtrr/cleanup.c
+++ b/arch/x86/kernel/cpu/mtrr/cleanup.c
@@ -189,6 +189,17 @@ x86_get_mtrr_mem_range(struct res_range *range, int nr_range,
                 if (!size)
                         continue;
                 base = range_state[i].base_pfn;
+                if (base < (1<<(20-PAGE_SHIFT)) && mtrr_state.have_fixed &&
+                    (mtrr_state.enabled & 1)) {
+                        /* Var MTRR contains UC entry below 1M? Skip it: */
+                        printk(KERN_WARNING "WARNING: BIOS bug: VAR MTRR %d "
+                                "contains strange UC entry under 1M, check "
+                                "with your system vendor!\n", i);
+                        if (base + size <= (1<<(20-PAGE_SHIFT)))
+                                continue;
+                        size -= (1<<(20-PAGE_SHIFT)) - base;
+                        base = 1<<(20-PAGE_SHIFT);
+                }
                 subtract_range(range, base, base + size - 1);
         }
         if (extra_remove_size)
diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
index 5c2e266f41d7..03cda01f57c7 100644
--- a/arch/x86/kernel/cpu/mtrr/main.c
+++ b/arch/x86/kernel/cpu/mtrr/main.c
@@ -574,7 +574,7 @@ struct mtrr_value {
         unsigned long   lsize;
 };
 
-static struct mtrr_value mtrr_state[MTRR_MAX_VAR_RANGES];
+static struct mtrr_value mtrr_value[MTRR_MAX_VAR_RANGES];
 
 static int mtrr_save(struct sys_device * sysdev, pm_message_t state)
 {
@@ -582,9 +582,9 @@ static int mtrr_save(struct sys_device * sysdev, pm_message_t state)
 
         for (i = 0; i < num_var_ranges; i++) {
                 mtrr_if->get(i,
-                             &mtrr_state[i].lbase,
-                             &mtrr_state[i].lsize,
-                             &mtrr_state[i].ltype);
+                             &mtrr_value[i].lbase,
+                             &mtrr_value[i].lsize,
+                             &mtrr_value[i].ltype);
         }
         return 0;
 }
@@ -594,11 +594,11 @@ static int mtrr_restore(struct sys_device * sysdev)
         int i;
 
         for (i = 0; i < num_var_ranges; i++) {
-                if (mtrr_state[i].lsize) 
+                if (mtrr_value[i].lsize)
                         set_mtrr(i,
-                                 mtrr_state[i].lbase,
-                                 mtrr_state[i].lsize,
-                                 mtrr_state[i].ltype);
+                                 mtrr_value[i].lbase,
+                                 mtrr_value[i].lsize,
+                                 mtrr_value[i].ltype);
         }
         return 0;
 }
diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.h b/arch/x86/kernel/cpu/mtrr/mtrr.h
index 6710e93021a7..77f67f7b347a 100644
--- a/arch/x86/kernel/cpu/mtrr/mtrr.h
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.h
@@ -79,6 +79,7 @@ extern struct mtrr_ops * mtrr_if;
 
 extern unsigned int num_var_ranges;
 extern u64 mtrr_tom2;
+extern struct mtrr_state_type mtrr_state;
 
 void mtrr_state_warn(void);
 const char *mtrr_attrib_to_str(int x);