[PATCH] cpu-hotplug: release `workqueue_mutex' properly on CPU hot-remove
_cpu_down() acquires `workqueue_mutex' on its process, but doen't release it
if __cpu_disable() fails.
Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 27dd3ee..663c920 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -150,18 +150,18 @@
p = __stop_machine_run(take_cpu_down, NULL, cpu);
mutex_unlock(&cpu_bitmask_lock);
- if (IS_ERR(p)) {
+ if (IS_ERR(p) || cpu_online(cpu)) {
/* CPU didn't die: tell everyone. Can't complain. */
if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED,
(void *)(long)cpu) == NOTIFY_BAD)
BUG();
- err = PTR_ERR(p);
- goto out_allowed;
- }
-
- if (cpu_online(cpu))
+ if (IS_ERR(p)) {
+ err = PTR_ERR(p);
+ goto out_allowed;
+ }
goto out_thread;
+ }
/* Wait for it to sleep (leaving idle task). */
while (!idle_cpu(cpu))
