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Diffstat (limited to 'arch/x86/kernel/cpu/bugs.c')
-rw-r--r--arch/x86/kernel/cpu/bugs.c26
1 files changed, 22 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index bd17db15a2c1..a44ef52184df 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -16,15 +16,19 @@
#include <asm/msr.h>
#include <asm/paravirt.h>
#include <asm/alternative.h>
+#include <asm/pgtable.h>
+#include <asm/cacheflush.h>
void __init check_bugs(void)
{
identify_boot_cpu();
-#ifndef CONFIG_SMP
- pr_info("CPU: ");
- print_cpu_info(&boot_cpu_data);
-#endif
+ if (!IS_ENABLED(CONFIG_SMP)) {
+ pr_info("CPU: ");
+ print_cpu_info(&boot_cpu_data);
+ }
+
+#ifdef CONFIG_X86_32
/*
* Check whether we are able to run this kernel safely on SMP.
*
@@ -40,4 +44,18 @@ void __init check_bugs(void)
alternative_instructions();
fpu__init_check_bugs();
+#else /* CONFIG_X86_64 */
+ alternative_instructions();
+
+ /*
+ * Make sure the first 2MB area is not mapped by huge pages
+ * There are typically fixed size MTRRs in there and overlapping
+ * MTRRs into large pages causes slow downs.
+ *
+ * Right now we don't do that with gbpages because there seems
+ * very little benefit for that case.
+ */
+ if (!direct_gbpages)
+ set_memory_4k((unsigned long)__va(0), 1);
+#endif
}