From: Greg KH on
2.6.32-stable review patch. If anyone has any objections, please let us know.


From: Peter Zijlstra <a.p.zijlstra(a)>

commit 933b0618d8b2a59c7a0742e43836544e02f1e9bd upstream.

A UP machine has 1 active cpu, not having the boot-cpu in the
active map when starting the scheduler confuses things.

Signed-off-by: Peter Zijlstra <a.p.zijlstra(a)>
Cc: Mike Galbraith <efault(a)>
LKML-Reference: <20091216170517.423469527(a)>
Signed-off-by: Ingo Molnar <mingo(a)>
Cc: Christoph Biedl <linux-kernel.bfrz(a)>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)>

init/main.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

--- a/init/main.c
+++ b/init/main.c
@@ -369,12 +369,6 @@ static void __init smp_init(void)
unsigned int cpu;

- /*
- * Set up the current CPU as possible to migrate to.
- * The other ones will be done by cpu_up/cpu_down()
- */
- set_cpu_active(smp_processor_id(), true);
/* FIXME: This should be done in userspace --RR */
for_each_present_cpu(cpu) {
if (num_online_cpus() >= setup_max_cpus)
@@ -486,6 +480,7 @@ static void __init boot_cpu_init(void)
int cpu = smp_processor_id();
/* Mark the boot cpu "present", "online" etc for SMP and UP case */
set_cpu_online(cpu, true);
+ set_cpu_active(cpu, true);
set_cpu_present(cpu, true);
set_cpu_possible(cpu, true);

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