From: Jay Lan Date: Mon, 11 Dec 2006 23:39:23 +0000 (-0800) Subject: [IA64] Do not call SN_SAL_SET_CPU_NUMBER twice on cpu 0 X-Git-Tag: v2.6.20-rc1~141^2~10 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=adf142e379bd20ad906a7e36f722eaabb3b44b0c;p=linux-2.6 [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 Signed-off-by: Tony Luck --- diff --git a/arch/ia64/sn/kernel/setup.c b/arch/ia64/sn/kernel/setup.c index a934ad0694..8571e52c2e 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