[IA64] Do not call SN_SAL_SET_CPU_NUMBER twice on cpu 0

This is an SN specific patch.

Architectually, cpu_init is always called twice on cpu 0
and thus resulted in two SN_SAL_SET_CPU_NUMBER calls.

This was harmless in production kernel; however, it can
cause problem on booting up a crashdump kernel at Altix.

Here is the patch that detects the second sn_cpu_init
call and skips the second call to SN_SAL_SET_CPU_NUMBER.

Signed-Off-By: Jay Lan <jlan@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/arch/ia64/sn/kernel/setup.c b/arch/ia64/sn/kernel/setup.c
index a934ad069425..8571e52c2efd 100644
--- a/arch/ia64/sn/kernel/setup.c
+++ b/arch/ia64/sn/kernel/setup.c
@@ -580,7 +580,7 @@ void __cpuinit sn_cpu_init(void)
         int slice;
         int cnode;
         int i;
-        static int wars_have_been_checked;
+        static int wars_have_been_checked, set_cpu0_number;
 
         cpuid = smp_processor_id();
         if (cpuid == 0 && IS_MEDUSA()) {
@@ -605,8 +605,16 @@ void __cpuinit sn_cpu_init(void)
         /*
          * Don't check status. The SAL call is not supported on all PROMs
          * but a failure is harmless.
+         * Architechtuallly, cpu_init is always called twice on cpu 0. We
+         * should set cpu_number on cpu 0 once.
          */
-        (void) ia64_sn_set_cpu_number(cpuid);
+        if (cpuid == 0) {
+                if (!set_cpu0_number) {
+                        (void) ia64_sn_set_cpu_number(cpuid);
+                        set_cpu0_number = 1;
+                }
+        } else
+                (void) ia64_sn_set_cpu_number(cpuid);
 
         /*
          * The boot cpu makes this call again after platform initialization is