x2apic: fix reserved APIC register accesses in print_local_APIC()

[deliverable/linux.git] / include / asm-x86 / apic.h

diff --git a/include/asm-x86/apic.h b/include/asm-x86/apic.h
index 2d970f6bc2a101f459b497d27d7ae7927614fc12..ef1d72dbdfe02b74d389c2067af12373db2cd3de 100644 (file)
--- a/include/asm-x86/apic.h
+++ b/include/asm-x86/apic.h
@@ -98,6 +98,20 @@ extern void check_x2apic(void);
 extern void enable_x2apic(void);
 extern void enable_IR_x2apic(void);
 extern void x2apic_icr_write(u32 low, u32 id);
+static inline int x2apic_enabled(void)
+{
+       int msr, msr2;
+
+       if (!cpu_has_x2apic)
+               return 0;
+
+       rdmsr(MSR_IA32_APICBASE, msr, msr2);
+       if (msr & X2APIC_ENABLE)
+               return 1;
+       return 0;
+}
+#else
+#define x2apic_enabled()       0
 #endif
 
 struct apic_ops {