Deadlock on poweroff

From: Kirill A. Shutemov
Date: Sat Oct 06 2012 - 22:46:22 EST


Hi Paul and all,

With commit 755609a9087fa983f567dc5452b2fa7b089b591f I've got deadlock on
poweroff.

It guess it happens because of race for cpu_hotplug.lock:

CPU A CPU B
disable_nonboot_cpus()
_cpu_down()
cpu_hotplug_begin()
mutex_lock(&cpu_hotplug.lock);
__cpu_notify()
padata_cpu_callback()
__padata_remove_cpu()
padata_replace()
synchronize_rcu()
rcu_gp_kthread()
get_online_cpus();
mutex_lock(&cpu_hotplug.lock);

Have you seen the issue before?

--
Kirill A. Shutemov
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/