[PATCH] xen/arm: missing put_cpu in xen_percpu_init

[Julien Grall]

When CONFIG_PREEMPT is enabled, Linux will not be able to boot and warn:
[    4.127825] ------------[ cut here ]------------
[    4.133376] WARNING: at init/main.c:699 do_one_initcall+0x150/0x158()
[    4.140738] initcall xen_init_events+0x0/0x10c returned with preemption imbalance

This is because xen_percpu_init uses get_cpu but doesn't have the corresponding
put_cpu.

Signed-off-by: Julien Grall <julien.grall at linaro.org>
---
 arch/arm/xen/enlighten.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index f71c37e..dc9f284 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -170,6 +170,7 @@ static void __init xen_percpu_init(void *unused)
 	per_cpu(xen_vcpu, cpu) = vcpup;
 
 	enable_percpu_irq(xen_events_irq, 0);
+	put_cpu();
 }
 
 static void xen_restart(char str, const char *cmd)
-- 
1.7.10.4