x86/mrst: Avoid reporting wrong nmi status

Moorestown/Medfield platform does not have port 0x61 to report
NMI status, nor does it have external NMI sources. The only NMI
sources are from lapic, as results of perf counter overflow or
IPI, e.g. NMI watchdog or spin lock debug.

Reading port 0x61 on Moorestown will return 0xff which misled
NMI handlers to false critical errors such memory parity error.
The subsequent ioport access for NMI handling can also cause
undefined behavior on Moorestown.

This patch allows kernel process NMI due to watchdog or backrace
dump without unnecessary hangs.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
[hand applied]
Signed-off-by: Alan Cox <alan@linux.intel.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c
index 701c7be442f1..c1d6cd549397 100644
--- a/arch/x86/kernel/x86_init.c
+++ b/arch/x86/kernel/x86_init.c
@@ -21,6 +21,7 @@
 #include <asm/pat.h>
 #include <asm/tsc.h>
 #include <asm/iommu.h>
+#include <asm/mach_traps.h>
 
 void __cpuinit x86_init_noop(void) { }
 void __init x86_init_uint_noop(unsigned int unused) { }
@@ -104,6 +105,7 @@ struct x86_platform_ops x86_platform = {
         .iommu_shutdown                 = iommu_shutdown_noop,
         .is_untracked_pat_range         = is_ISA_range,
         .nmi_init                       = default_nmi_init,
+        .get_nmi_reason                 = default_get_nmi_reason,
         .i8042_detect                   = default_i8042_detect
 };