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@xxxxxxx> The patch is created off 2.6.19.
Index: linux/arch/ia64/sn/kernel/setup.c
===================================================================
--- linux.orig/arch/ia64/sn/kernel/setup.c 2006-11-29 13:57:37.000000000 -0800
+++ linux/arch/ia64/sn/kernel/setup.c 2006-12-11 15:31:16.700848251 -0800
@@ -562,7 +562,7 @@ 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()) {
@@ -587,8 +587,16 @@ 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
|