From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Fri, 17 Feb 2006 21:52:46 +0000 (-0800)
Subject: [PATCH] s390: fix preempt_count of idle thread with cpu hotplug
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1fca251f36fac3fae7d9cf10de69c2c93f6c0000;p=linux-beck.git

[PATCH] s390: fix preempt_count of idle thread with cpu hotplug

Set preempt_count of idle_thread to zero before switching off cpu.  Otherwise
the preempt_count will be wrong if the cpu is switched on again since the
thread will be reused.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 008c74526fd3..da6fbae8df91 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -128,8 +128,10 @@ void default_idle(void)
 	__ctl_set_bit(8, 15);
 
 #ifdef CONFIG_HOTPLUG_CPU
-	if (cpu_is_offline(cpu))
+	if (cpu_is_offline(cpu)) {
+		preempt_enable_no_resched();
 		cpu_die();
+	}
 #endif
 
 	local_mcck_disable();