From: Zwane Mwaikambo <zwane@arm.linux.org.uk>
This fixes an oops due to cpu_sibling_map being uninitialised when a system
with no MP table (most UP boxen) boots a CONFIG_SMT kernel. What also
happens is that the cpu_group lists end up not being terminated properly,
but this oops kills it first. Patch tested on UP w/o MP table, 2x P2 and
UP Xeon w/ no siblings.
---
25-akpm/arch/i386/kernel/smpboot.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)
diff -puN arch/i386/kernel/smpboot.c~sched-find_busiest_group-fix arch/i386/kernel/smpboot.c
--- 25/arch/i386/kernel/smpboot.c~sched-find_busiest_group-fix Wed Feb 4 12:30:01 2004
+++ 25-akpm/arch/i386/kernel/smpboot.c Wed Feb 4 12:30:01 2004
@@ -953,6 +953,8 @@ static void __init smp_boot_cpus(unsigne
current_thread_info()->cpu = 0;
smp_tune_scheduling();
+ cpus_clear(cpu_sibling_map[0]);
+ cpu_set(0, cpu_sibling_map[0]);
/*
* If we couldn't find an SMP configuration at boot time,
@@ -1085,7 +1087,7 @@ static void __init smp_boot_cpus(unsigne
* efficiently.
*/
for (cpu = 0; cpu < NR_CPUS; cpu++)
- cpu_sibling_map[cpu] = CPU_MASK_NONE;
+ cpus_clear(cpu_sibling_map[cpu]);
for (cpu = 0; cpu < NR_CPUS; cpu++) {
int siblings = 0;
@@ -1305,7 +1307,7 @@ __init void arch_init_sched_domains(void
for_each_cpu_mask(j, cpu_domain->span) {
struct sched_group *cpu = &sched_group_cpus[j];
- cpu->cpumask = CPU_MASK_NONE;
+ cpus_clear(cpu->cpumask);
cpu_set(j, cpu->cpumask);
if (!first_cpu)
_