summaryrefslogtreecommitdiff
path: root/include/asm-x86
diff options
context:
space:
mode:
authorYinghai Lu <yhlu.kernel@gmail.com>2008-09-03 23:58:31 (GMT)
committerIngo Molnar <mingo@elte.hu>2008-10-16 14:53:04 (GMT)
commita11b5abef50722e42a7d13f6b799c4f606fcb797 (patch)
treeeed224f07b6c8fc20cc4a454578e34721999b763 /include/asm-x86
parentc59d85a7b7822b83fc9783314543eea0ca860480 (diff)
downloadlinux-a11b5abef50722e42a7d13f6b799c4f606fcb797.tar.xz
x2apic: fix reserved APIC register accesses in print_local_APIC()
APIC_ARBPRI is a reserved register for XAPIC and beyond. APIC_RRR is a reserved register except for 82489DX, APIC for Pentium processors. APIC_EOI is a write only register. APIC_DFR is reserved in x2apic mode. Access to these registers in x2apic will result in #GP fault. Fix these apic register accesses. Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/asm-x86')
-rw-r--r--include/asm-x86/apic.h14
1 files changed, 14 insertions, 0 deletions
diff --git a/include/asm-x86/apic.h b/include/asm-x86/apic.h
index 2d970f6..ef1d72d 100644
--- 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 {