1 files changed, 13 insertions, 0 deletions

diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c
index 3d76dbd9f2c0..b5425979501c 100644
--- a/arch/x86/kernel/setup_64.c
+++ b/arch/x86/kernel/setup_64.c
@@ -729,6 +729,19 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
 
         if (amd_apic_timer_broken())
                 disable_apic_timer = 1;
+
+        if (c == &boot_cpu_data && c->x86 >= 0xf && c->x86 <= 0x11) {
+                unsigned long long tseg;
+
+                /*
+                 * Split up direct mapping around the TSEG SMM area.
+                 * Don't do it for gbpages because there seems very little
+                 * benefit in doing so.
+                 */
+                if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg) &&
+                (tseg >> PMD_SHIFT) < (max_pfn_mapped >> (PMD_SHIFT-PAGE_SHIFT)))
+                        set_memory_4k((unsigned long)__va(tseg), 1);
+        }
 }
 
 void __cpuinit detect_ht(struct cpuinfo_x86 *c)